How to overhaul an engine. Do-it-yourself overhaul of a VAZ engine

14.10.2019

Regardless of the complexity and reliability of an automobile engine, each of them has its own specific resource - over time, engine parts wear out.

Repair of internal combustion engines (internal combustion engines) is required prematurely if the power unit fails due to careless operation. The cause of a motor failure can be:

overheat;
insufficient oil level in the engine crankcase;
operation of the car in difficult road conditions or in violation of the speed limit;
installation of parts of inadequate quality;
unqualified assembly.

Most often, the overhaul of internal combustion engines is carried out in specialized car services, but not so rarely, car owners repair engines with their own hands - a lot depends on the complexity of the power unit.

Do-it-yourself internal combustion engine overhaul

When performing an overhaul of the engine on their own, the driver must calculate his strength, since the repair of an internal combustion engine is not an easy task, it requires certain knowledge, locksmith skills, care and accuracy. Each engine model has its own design features, and when repairing a power unit, they must be taken into account.

Any overhaul of the internal combustion engine consists of the following operations:

withdrawal;
disassembly;
Troubleshooting (rejection of parts to be replaced);
crankshaft grinding;
lapping of valves of the head of the block;
assembly;
motor installation;
launch;
adjustment;
running-in.

After repairing the engine, it is necessary to operate the car for the first time with minimal loads:

drive at low speeds, preferably no more than 80 km / h;
do not overload the trunk, interior or body;
do not over-rev the engine.

The complexity of repair work depends on the type of engine - on trucks, overhaul takes more time and physical effort. Of course, the overhaul of the internal combustion engines of such trucks as GAZ, KAMAZ or ZIL will last longer than the overhaul of a VAZ, in addition, for the repair of large engines, a room of an appropriate area is required.

Each engine model has its own nuances:

the weakest points;
disassembly and assembly features.

Further in this article, we will consider the possible weaknesses of Ford, Mazda, Nissan, Mercedes and Toyota passenger car engines, and at the end we will pay attention to some features of the repair of domestically produced engines - GAZ and VAZ.

Among modern Ford ICEs, there are three main types of engines - Split Port, Duratec and Zetec, basically all Ford cars (Focus, Mondeo, Fusion, etc.) are equipped with 1.4 / 1.6 / 1.8 / 2 engines, 0 l. All Ford internal combustion engines themselves are very reliable, they take care of their prescribed resource without problems (at least 250 thousand km), and most often fail ahead of time due to the fault of the drivers themselves.

All Duratec engines are chain driven, Zetec engines are only available with timing belts. "Zatek" motors on Fords are of two types:

Zetec E;
Zetec SE.

An improved version of the Zetec-SE ICE was developed by Mazda and Yamaha, it differs from the standard Zetec E in the location of the manifolds - the intake and exhaust systems are located on opposite sides of the engine. The Zetec-SE engine was the first to use a plastic intake manifold.

Split Port is a purely American-designed motor, the internal combustion engine itself and spare parts for it are produced only in America. Among all types of Ford engines, the Split Port modification is the most problematic, the main disease is the departure of the block head seats from under the valves. The outgoing seat breaks the pistons, often the cylinder head itself is damaged, and the repair is quite expensive.

Mercedes engines

There are many different types of engines in the line of power units of Mercedes cars, the most popular are gasoline engines:

four-cylinder M111;
six-cylinder M112 and M104;
eight-cylinder M113.

The M111 and M104 internal combustion engines are in-line, highly reliable and have a long service life, although the M111 is somewhat noisy in operation. ICEs M112 and M113 have a V-shaped arrangement of cylinders - these engines have increased oil consumption, it is possible that the crankshaft pulley damper will delaminate at a run closer to 100 thousand km.

Compared to Ford engines, Mercedes car engines are mostly larger, for example, the M119 E50 ICE modification is five-liter, V-shaped, eight-cylinder. M119 motors are distinguished by a small chain resource - parts require replacement on average at a mileage of 100-150 thousand km. Other problems with M119 engines rarely occur, and if you change the chain drive on such an engine in time, it can travel up to 500 thousand km without a “capital”.

on many models of engines, the chain stretches after 150 thousand kilometers;
when overheated, the cylinder head quickly fails.

Basically, gasoline engines do not cause any complaints from car owners, the most problematic at Nissan are diesel engines with a volume of more than 2.8 liters. The RD28 internal combustion engine (2.8 l) does not tolerate overheating, first of all, the cylinder head fails on a diesel engine (cracks appear in the block head). Other problems occur on the ZD30 power unit:

On Mazda cars, Ford engines are quite common, in particular, the two-liter engine on the Mazda-3 car is similar to the power unit installed on the Ford Mondeo. Even on the Mazda RX7 and RX8 car models, rotary-piston engines of the Japanese concern's own design were installed, but the power units did not gain much popularity in Russia - these engines have a small resource, and already at a run of about 100 thousand km they need a major overhaul.

Among the Mazda ICEs, the Z-series engines are widely used - this is a series of 4-cylinder gasoline engines with a volume of 1.3 to 1.6 liters. All power units of Z-engines are 16-valve, in-line, with two camshafts in the BC head. The cylinder block can be cast both from cast iron (models Z5, ZL and ZM) and from aluminum (Z6, ZY, ZJ), Mazda-323, Mazda-3, Mazda Demio are equipped with these motors. The Z-series ICE does not have hydraulic lifters, and the valves on them have to be adjusted quite often. Also, these motors have other problems:

due to faulty intake manifold flaps, a "diesel" sound occurs;
failure of the EGR valve due to low-quality fuel.

In general, Z motors are reliable, the timing chain changes on a run no earlier than 200-250 thousand km.

Toyota engines

Toyota power units are highly reliable, for the entire period of the company's existence, power units of various sizes and modifications have been installed on cars, for convenience, all Toyota engines are divided into series:

A (the most famous models are 4A-FE, 7A-FE,);
E (the most popular engines are 4E-FE, 5E-FE);
G (1G-FE);
S (the most widely used 3S-FE and 4S-FE);

There are a lot of different series, and basically all power units are quite successful in their design and reliability. But among Toyota engines there are also not too ICEs, in particular, the VZ series of V-shaped ICEs has not proven itself from the best side, among their shortcomings are noted:

failure of the cylinder heads (the appearance of cracks in them due to overheating);
increased oil consumption;
quite high fuel consumption.

Engines manufactured by ZMZ are installed on cars of the Gorky Automobile Plant, recently GAZ trucks and commercial vehicles are equipped with power units from UMZ, YaMZ, Cummins. The engines of the ZMZ-402 series have already been discontinued, but there are quite a lot of different vehicles with these engines to drive on the roads of our country and abroad.

The main problems of ZMZ-402:

oil leak from the rear oil seal;
increased oil consumption;
the need for frequent valve adjustments.

An oil seal is installed on the back of the crankshaft on the 402nd motor to minimize oil leakage, it is necessary to apply an oil-resistant sealant to the joints of the seals.

The main problem of the ZMZ 405/406 internal combustion engine is the rather short service life of the timing chains, the parts of the gas distribution mechanism need to be replaced after about 70-80 thousand kilometers. There is a big plus in the timing of 406 engines - when the chains break, the valves in the block head do not bend, and therefore replacing chain drive parts is not too expensive. There are quite a few complaints about the engine of the Ulyanovsk Motor Plant, it has the following shortcomings:

increased oil loss through piston rings;
tendency to overheat, and as a result, failure of the block head and piston group;
a small common resource - often the motors "capitalize" already in the first hundred thousand kilometers.

The Cummins turbodiesel is considered an excellent high performance engine and this engine:

economically consumes fuel;
has good dynamics;
able to run 500 thousand km without overhaul.

But the Cummins resource declared by the manufacturer does not always work out, the turbodiesel has its drawbacks:

VAZ engines

Power units of VAZ production are relatively reliable and not critical to the quality of the fuel used, especially 8-valve engines are "omnivorous". During normal operation, VAZ engines have a good resource - if the internal combustion engine is not overheated and not overloaded, it will run 200 thousand km or more without problems. In order for the motor to depart its due date, it is necessary:

fill in high-quality engine oil from well-known manufacturers (synthetic or semi-synthetic);
do not exceed the speed limit;
carry out maintenance in a timely manner (oil change - every 10 thousand km);
with a frequency of every 60 thousand km, replace the timing belt.

Recently, motors of models are mainly installed on VAZ cars:

11183 (21114);
11186 (21116);
21126;

All internal combustion engines have a volume of 1.6 liters, and, unfortunately, on all of the listed models, except for 11183, when the timing belt breaks, the valves meet with pistons. The impact of valves on the pistons during a break in the timing belt drive causes a lot of trouble - in some cases, the block head fails, the pistons are destroyed. The 8-valve VAZ-11183 engine is the simplest and most trouble-free of all those listed, but it is also the most low-powered.

Overhaul of the engine, or the eyes are afraid, but the hands are doing.

Background.
It all started, as you know, with the purchase of a “non-new” car in 2009. Car VAZ 21053 1997 color "safari" code 215 (for those who are not in the know - light beige). After the purchase, I skated no more than a couple of thousand kilometers, and soon the engine refused to pull normally. I checked the spark plugs - relatively clean, adjusted the valves - did not help. Having obtained a homemade compression gauge, and measuring the compression, I was unpleasantly surprised.

The compression was:
1 - 8;
2 - 8;
3 - 4,5;
4 - 8.
Here it’s a no brainer that only an autopsy will save the patient. Like many brothers in misfortune, I started by calling services, and, having learned the cost of repairs (15-17 thousand rubles only for work), I made a unanimous decision to make repairs using the forces of my limbs and gray matter.

And so, the age-old question, to which I did not find a detailed answer on the forums: “The capital of the engine, what and how to do?”.

I'll start, perhaps, with a list of special tools that may be needed for this ritual:
set of heads;
a mandrel for piston rings (about 260 rubles, but you can make it yourself from a sheet of tin);
mandrel valve stem seals (20 rubles);
valve cracker (80-100 rubles);
torque wrench (it is necessary to take such that the size of the tetrahedron is the same as on the heads) (1300r);
micrometer (500-600 rubles);
clutch disc mandrel (50 rubles);

Ratchet key (80 rubles);

A device for adjusting valves with an hour indicator (500-800 rubles);
two- or three-legged puller (400-500 rubles).

For spare parts:
pistons;
piston rings;
main and connecting rod bearings;
crankcase gasket;
block gasket;

Literature:
Repair manual for your car;
spare parts catalog

Next in order.
1. We put the machine in the place where you will carry out repairs. The ideal option is a garage with a viewing hole.
2. Remove the hood from the car. Better with two people, but I did it alone.
3. Disconnect the battery and remove it from the car.
4. Drain the engine oil and coolant (coolant). If the state of the coolant suits you, then you need to drain it carefully. Bolts are installed in the radiator and cylinder block from the factory, so some part of the coolant will spill past. I would advise you to go to the store for faucets (the issue price is 40 rubles apiece). By quickly changing the plugs to taps, you can carefully drain the coolant through the hose.
5. Remove the air filter housing (pan), remove the carburetor from the intake manifold and put it where it will not interfere with us. Disconnect the fuel line from the fuel pump and plug it with an M8 bolt. We remove the fuel pump, the fuel pump rod along with the gaskets and spacer.
6. Disconnect the pipes going to the heater, and disconnect the wire from the coolant temperature sensor. We disconnect the high-voltage wires from the candles and remove the distributor. Remove the oil separator.
7. Remove the cylinder head cover. Remove the sprocket from the camshaft and then the camshaft itself.
8. We unscrew the M6 studs from the cylinder head so that they do not interfere, with the help of two nuts screwed onto the stud and locked together.
9. We take a knob, an extension cord and a 12 head and try to unscrew the cylinder head bolts. This is not as easy as it might initially seem, especially if the cylinder head was pulled up “hot” or simply without a torque wrench. I broke 3 heads while removing the cylinder head. When unscrewing, make sure that the head does not warp on the bolt head. If for some reason the bolt does not lend itself (the edges on the head are torn off), then it must be drilled out. First, we core a point in the center of the cap and drill with a drill with a diameter of 4-5 mm to a depth of 15 mm. Then we drill with a drill with a diameter of 12 mm to the same depth. It is better to determine the depth approximately with a caliper so as not to drill the head. Next, we take a punch, put it in the center of the drilled hole in the hat and apply a couple of sharp blows with a hammer. The cap should bounce off the bolt.
10. We unscrew the four nuts securing the intake pipe and, having removed it from the studs, take it aside. We remove the cylinder head along with the manifolds, and if we are not going to disassemble it, then we set it aside closer to the removed carburetor.
11. We are trying to make out the cylinder markings embossed on the piston bottom. This is necessary in order to know which pistons to buy and what size to sharpen. As for the pistons: I immediately took the Motordetal kit (pistons, fingers, rings), this frees me from the weight of the pistons. The only thing you need to check is the fit of the finger in the piston; it should enter the piston from the effort of the thumb and not fall out of the piston in a vertical position.
12. We remove the crankcase protection and the engine boot (if any), disconnect the wiring from the generator and remove the generator and belt from the machine.
13. Remove the starter cover and hot air intake. We turn off and remove the starter (attached with 2-3 bolts to the clutch housing).
14. Remove all pipes. Remove fan shroud and heatsink. We remove the pump.
15. With a crowbar we fix the flywheel from turning and with a ratchet wrench we unscrew the nut securing the KV pulley.
16. Unscrew the 4 bolts securing the clutch housing and two nuts on the engine mounts.
17. Remove the engine from the car. Here the method is determined by the place of repair. I had a beam above the pit, so there were no problems with securing the winch. Do not forget to invite an assistant for this action.
18. We turn the engine upside down with the crankcase, while monitoring the integrity of the two guide bushings in the upper part of the block. It is better to put the engine on wooden blocks.
19. Remove the clutch from the flywheel and the flywheel itself. Remove the clutch housing boot.
20. Remove the oil filter. We unscrew the crankcase mounting bolts and remove the crankcase from the block. We do this carefully so as not to break off the oil intake.
21. Remove the rear cover of the block along with the gland and the front.
22. Remove the star from the pig. Unscrew the chain stop and remove the tensioner shoe. We remove the chain. Remove the KV sprocket with a puller (although I removed it by hand).
23. We unscrew the nuts on the connecting rod caps, remove the caps, lower the pistons down and remove the liners. After evaluating the condition of the liners and necks of the CV, we decide whether to reuse or replace the liners. If the liners are left old, then their former location should be remembered. If you change, then you should first look at the marking on the non-working side of the insert: if there is no marking, then the inserts are nominal, the first repair is +0.25, the second is +0.50. If there is a visible and tangible wear on the necks of the CV, then it is necessary to turn the necks to the next repair size and, accordingly, the mandatory replacement of the liners with the corresponding repair size.
24. We repeat the previous paragraph for the indigenous. Naturally, pistons with connecting rods do not need to be moved. We remove the HF from the block and the thrust half rings.
25. We remove the pig. Remove the oil pump and remove the oil pump drive gear. We turn the block on its side and remove the pistons with connecting rods from the cylinders.
26. We go to the store and buy a piston of the right size (we don’t pay attention to the class of pistons). At the same time, we are looking for a workshop for boring the block, grinding the KV and pressing the piston pins. You need to bring the block to the bore with a set of new pistons so that the cylinders are machined for specific pistons. A normal borer will mark the pistons after the block has been bored.
27. We measure the necks of the KV after processing with a micrometer, according to the manual we determine the size of the liners and go to the store for the liners. Do not believe in the myth that after the capital investment, the car will have to be towed. Those who do this in advance take thicker liners than necessary and clamp the HF. Then, when towing, they try to disrupt this business. And then there are problems: either the liners will turn, or the torn metal from the liners will clog the oil channels of the HF. In any case, such an engine will not live long. With the correct selection of liners, the HF will rotate by hand.

Engine assembly.
1. We inspect the block for the absence of metal chips. Where possible we remove carbon deposits. And in the future, I recommend cleaning parts from carbon deposits as much as possible so that the new oil works for lubrication and not for cleaning parts from carbon deposits.
2. We clean the beds of the main bearings from dirt, lubricate the beds with engine oil, the liners and put them in the bed guided by the lock. The main liners are different, read the repair manual, it says which ones go where. Use the same oil that you are going to fill in after the repair, it is not known how oils of different brands mixed together will behave. We install persistent half rings on the back wall of the block with grooves to the HF planes. We put the KV in the block, install the covers with liners, observing the markings on the covers and the location of the locks on the covers and in the block (they should be on the same side), we twist and tighten the bolts with a torque wrench. We check the rotation of the KV. If the HF does not rotate, then they miscalculated with the liners and they need to be replaced with thinner ones.
3. It is better to order the piston assembly in the service, of course, under your own control (not everyone has the opportunity to heat the connecting rod heads to 240 degrees). If the connecting rod has a hole for supplying oil to the liners (of a Soviet-built engine), then during assembly this hole should be on the side of the letter P (front side) on the piston. If there is no such hole, then, as knowledgeable people said, the connecting rod must be set so that the lock is on the right side when looking at the piston from the side of the letter P (although the manual says that you can put it as God puts it on your soul).
4. Lubricate the piston pins in the pistons through the holes. We put rings on the pistons. The lower one is oil scraper (the one with a spring inside), and two compression ones (they are of different thicknesses, so you can’t go wrong), we check the closure of the rings and open the locks at angles of 120 degrees, while making sure that the locks do not fall on the holes and slots in pistons. Lubricate the rings and mandrel with oil and tighten the mandrel on the piston, remembering the location of the front side of the piston. We put the block on its side and insert the piston with the connecting rod into the cylinder according to the markings on the piston made during boring. Gently tapping with a hammer handle or a wooden block pushes the piston into the cylinder.
5. Turn the block up KV. We pull the connecting rods to the necks and fix them in the same way as the main ones. See manual for tightening torque. Be sure to check the ease of rotation of the HF. If it doesn't spin, then change the bushings.
6. Secondary check the tightening of all caps and connecting rods.
7. We replace the KV rear oil seal in the cover and put the cover on the block, not forgetting to install the anther mounting bolts (they are with a four-sided head) and smearing the mating planes with a sealant-gasket.
8. We put the boot of the clutch housing on the block. We install the flywheel in such a way that the groove on the flywheel is on the side of the 4th knee KV !!!
9. We put back the asterisk KV, assessing its condition in advance. I changed all the sprockets and the chain, because they did not inspire confidence and there was no desire to climb into the engine again. We put the chain on the sprocket, install the restrictive finger, put the pig in place, fasten the bracket and install the sprocket on it (do not forget to counter it after tightening it with a washer, preferably a new one). Install the tensioner shoe.
10. Having replaced the front seal of the CV, lubricate the mating planes and install the front cover, centering the position of the seal and the front end of the CV and fix it. We put the KV pulley in place and tighten the ratchet nut holding the KV from turning
11. We put back the oil pump, a new crankcase gasket and fix it with bolts.
12. We put the clutch on the flywheel, centering the position of the disc with a mandrel, and evenly tighten the clutch mounting bolts.
13. We install the engine on the car, while the engine mounts should not be fixed to the frame. If the box is not removed from the car, then you will have to sweat when combining the gearbox and engine. We fasten the gearbox to the engine with bolts and fix the ground wire from the bottom to the gearbox (if you forget, then you will suffer with the starter later !!!).
14. We check the blind holes for the cylinder head bolts for the absence of oil and other liquids so that the block does not burst when tightened !!! We put the cylinder head on the block (with a new gasket !!!), pull the chain through the cylinder head and fasten it (the chain) with wire so as not to miss it in the crankcase. We tighten the bolts with a torque wrench (be sure to check all the bolts for the absence of hood and the condition of the bolt heads).
15. We put the oil pump drive gear in the block, assemble the oil separator.
16. We set the position of the CV along the long mark of the cover, put the sprocket on the chain so that the mark on the sprocket is at the top, put the sprocket on the camshaft and combine the mark on the camshaft bed and the mark on the sprocket. Carefully removing the sprocket, we put the camshaft on the cylinder head. We put the sprocket on the camshaft, check the coincidence of the marks and tighten the camshaft mounting nuts. We fix the asterisk, we counter the bolt with a lock washer.
17. We catch the moment when the first piston is at TDC by pressing the intake valve (it will be pressed before TDC) and set the KV to +5º. We put the battery in place and connect the wires. We connect the candle to the high-voltage wire of the first candle and put it with its body on the ground. On the distributor, we put the slider opposite the contact of the 1st cylinder and put the distributor in place, placing the cover latches along the engine. We turn on the ignition and by turning the distributor we look for the position at which a spark appears on the candle. In this position, we fix the distributor, now we have the ignition set ahead of + 5º.
18. We adjust the chain tension and clearances in the valve mechanism. We put the cylinder head cover with a new gasket in place.
19. We put the carburetor in place, put the oil pressure sensor, the coolant plug in the block, the oil filter and fill in the oil.
20. We put the pump in place. We put the generator, connect the wires to the generator. Install the alternator belt and set the belt tension.
21. We put the radiator and connect all the hoses of the cooling system and the expansion tank. Pour coolant into the system, check for coolant leaks.
22. We wrap the candles, put high-voltage wires on the candles.
23. We put the starter in place and tighten the bolts. We connect the wiring to the starter.
24. We fix the intake pipe on the collector.
25. Install the fuel pump and connect the fuel line.
26. Trying to start the engine. After setting the ignition timing according to paragraph 17, my engine started the first time. I advise you to warm up the engine to operating temperature, while monitoring the absence of oil and coolant leaks. If suddenly the coolant leaks from under the cylinder head, then tighten the cylinder head only on a cold engine !!!
27. We put in place the pan, protection and boot of the engine, fan shroud and hood.

Engine capital has been completed. Now the first 2500 km should be driven carefully without sudden acceleration, without overloading the engine. After a run of 2500 km, change the oil in the engine. Look under the hood often to check the unit.

Advice for those who will disassemble the cylinder head.
As you know, a regular cracker is not a very convenient thing and easily flies out of gear on a hairpin. I advise you to wrap two nuts on the hairpin and clamp the grip of the device between them, then the chance of getting the device on the forehead will be minimal.

P.S. Maybe I missed something, but I hope I described the main points.

Good luck with this difficult task.

AvtoVAZ, the manufacturer set the average mileage for VAZ 2114 cars = 150 thousand km. The same indicators have, on average, all Russian cars. But, if various problems are eliminated in time, the resource of motors can easily withstand 250 thousand km. The resource of engines of foreign cars, on average, is 200,000 - 300,000 km before overhaul.

What is included in an engine overhaul

Overhaul of diesel and gasoline engines is done in stages:

Disassembly of the engine.
Parts washing and cleaning.
After cleaning, an experienced auto mechanic is able to determine how worn out certain parts are, whether they can be repaired or better replaced. Troubleshooting is done, that is, after the cylinder head (cylinder head) has been removed, it and the cylinder block (cylinder head) are checked for chips and cracks; examine the cylinders for scuffs and scratches; determine the gaps of the mating parts; inspect the condition of the pistons for the presence of chips, shells, soot; inspect the crankshaft connecting rods; study of the crankshaft of the internal combustion engine; fingers; bearings; parts of the gas distribution mechanism are also checked (valves, rocker arms, etc.). They also compare the dimensions of important parts with the factory ones.
After troubleshooting, it is necessary to assess the degree of wear of the entire engine: what to change, what to leave, what to repair.

If you have never had to completely disassemble the engine, then it would be more correct and better to invite a friend who understands.
It is desirable to carry out disassembly in a warm and well-lit garage.
During disassembly, put all bolts, washers and nuts in a box with partitions, do not throw everything into one bucket.
During disassembly, remember the sequence if you are doing this for the first time.
If you don't know what the spare parts are called, take the old parts to the store and show them to the seller.

Do-it-yourself engine overhaul

In our do-it-yourself engine overhaul guide, here is the sequence of actions:

Dismantling and disassembly.
Parts troubleshooting.
Washing of disassembled parts.
Order and purchase of spare parts.
Block and crankshaft grinding.
Block head repair.
Verification work.
Assembly and installation of internal combustion engines.
Running after capital.
Conclusion.

Dismantling and disassembly

Depending on the make and model of the car (engine design, number of cylinders, gearbox type), the process of dismantling the engine may differ. The location of the engine on front-wheel drive and rear-wheel drive is also different.

Carburetor engines are much easier and faster to disassemble, since they are not crammed with electronic devices, in the presence of which, in order to get to the engine itself, you have to carefully dismantle them all.

So, if you have to make a capital for Kamaz, for example, then its diesel engine from the Yaroslavl plant YaMZ-236 will take about 10 hours to dismantle. If you do the same work with heavy-duty analogues of Kamaz, it will take more than 30 hours.

And to disassemble the VAZ engine, you need about 3 hours. And the engines of passenger cars will take about 10 hours.

It is necessary to disassemble slowly, throwing bolts and nuts anywhere. With disassembly, the diagnostics, so to speak, have already begun.

Troubleshooting of elements during the capitalization of internal combustion engines

Troubleshooting in this case is mechanical, that is, it is necessary to check visually and with the help of measuring instruments the wear of parts.

The troubleshooting of the internal combustion engine includes the following work:

inspect the crankshaft and measure its dimensions, check for bends and centering;
inspect the cylinder block housing (BC);
check the details of the connecting rod-crank mechanism for backlash and the condition itself: pistons, cylinders, rings, fingers, connecting rods;
inspect the cylinder head housing (cylinder head);
details of the gas distribution mechanism;
determine the maintainability of parts and assemblies.

Washing the engine and individual parts after disassembly

Many neglect such work as washing the motor. It is advisable to rinse each part and clean it of plaque so that you can determine the degree of wear, also rinse the cylinder head and BC to detect macrocracks, if any.

What parts are needed for engine overhaul

After doing the troubleshooting procedure and screening out those that are suitable for restoration and those that are not suitable, it is necessary to order new parts to replace the unusable ones. When you already know what spare parts are needed, you don’t have to delay with their order and purchase, since new parts still need to be prepared for installation.

Spare parts for overhaul for gasoline engines:

Inserts (main and connecting rod).
Details of the piston group.
Connecting rod fingers.
Connecting rod bushings.
Valves (all, both inlet and exhaust).
Oil scraper rings.
Gaskets (complete set).
Valve guides and valve seats.
Pump with repair kit.
Oil filter and pump.
Other associated parts.

Block and crankshaft grinding

After the issue with spare parts has been resolved, they begin to repair and restore the block and the crankshaft of the internal combustion engine. On a milling and surface grinding machine, a layer of the seat of the cylinder head and the block itself are removed until there are no shells and chips left. It happens that there are several deep shells, because of which you have to remove layers in several passes. Usually, depending on the degree of damage, layers are cut off with a thickness of 1 mm, 0.5 mm, 0.25 mm, 0.1 mm, 0.05 mm. After that, they begin to grind the surface to a mirror finish.

There is a special table for grinding the crankshaft, which indicates the thickness and efficiency after repair compared to a new factory one.

Type of repair	Thickness, mm	Efficiency compared to new
Repair No. 1	0,25	80-90%
Repair No. 2	0,50	70-75%
Repair No. 3	0,75	65-70%
Repair No. 4	1,00	50-55%
Repair No. 5	1,25	40-45%
Repair No. 6	1,50	Less than 30%
Repair No. 7	2,00	Not used since 1995

Repair of the head of the block (cylinder head of the internal combustion engine)

For repair work with the cylinder head, although not difficult, for some reason many try to give it to the service.

Repair of the block head consists of the following types of work:

We replace the camshaft (everything that is in this engine).
Change suction and exhaust valves.
Change guide bushings.
with saddles.
If there are cracks in the cylinder head, then either we change the head and grind it again, or we weld these cracks with argon.

Verification work

After the main repair and restoration work done, there are still verification and additional ones. This includes clutch alignment and engine pressure testing.

For centering, some services provide special centering stands. The connection between the crankshaft and the clutch must be centered. A balanced crankshaft and clutch will reduce wear and friction as well as end runout.

Assembly and installation of internal combustion engines

Engine assembly sequence after overhaul:

If for the first time you decide to make a capital box with your own hands, after all the work before assembly, it is better to assemble with an experienced specialist in this matter. The resource of the entire car depends on the build quality.

Break-in after capital

The most enjoyable process in such work is the running-in necessary for the engine with new parts. During the break-in, new parts are rubbed in, so it is not recommended to immediately give a large load. It is recommended to run a run-in up to 2000 km without jerks and a sharp start.

There are several ways to roll:

Running on a cold stand.
Cold running without stand. This method is common, especially in the CIS countries. After preparing everything you need (engine oil and coolant are filled in), without starting the engine, roll the car in tow at 3 speeds for 2 hours. This method is not recommended. By the way, a very important reminder: engine oil has a code and designations for additives, before purchasing it, it is advisable to learn, after which you can make the right choice yourself.
Hot run. This method consists in starting the engine and letting it idle for 3 minutes, then turning off the engine. And so they do it several times, only waiting for the engine to cool down. Then, after short-term starts, the engine is started and allowed to run for 1 hour. During the break-in, the engine is inspected for tightness and other indicators. After running in, adjust the valve clearances and set the desired ignition. If contact ignition is installed, then it is recommended, instead of the old one,. It reduces fuel consumption and generates a high voltage of up to 24 kilovolts, while contact ignition is capable of supplying no more than 18 kilovolts to a candle. Thanks to this, they even give a spark.
Natural rolling. It is run in under the following conditions: smooth driving, speed no more than 60 km. After overhaul without installing new liners, running-in is carried out up to 2 thousand km. If new sleeves were installed, then 4 thousand km.

Abroad, they say, in car services there are break-in and test benches for internal combustion engines. This stand with the help of special electronics shows the resource of the restored engine.

If you still decide to do the overhaul not on your own, but to give it to the service, then you will receive a guarantee for the repaired motor. The guarantee is given by someone like, someone is 20 thousand kilometers, someone is 30 thousand km. run.

Do-it-yourself engine overhaul is only partially possible. Because, we need machines, the cylinder head and cylinder head have to be given for boring and grinding. The rest of the work can be done by yourself. The simpler the car, the easier it is to make repairs. It is not difficult to independently make capital on VAZ, GAZ, UAZ, NIVA cars.

To increase the engine resource of any car, you need:

buy high-quality spare parts and consumables;
timely maintenance;
the most important thing is to change the engine oil every 6-7 thousand kilometers;
a neat smooth ride without jerks also increases the life of the car.

After an overhaul of the engine, the oil must be changed at the following intervals:

After 500 km - the first change.
After 1000 km - the second replacement.
After 1500 km - the third oil change.
After 2000 km - the fourth replacement and, further on schedule, every 10-15 t.km.

The video shows some types of work on the overhaul of internal combustion engines.

The car engine does not last forever. Consider the question: how to determine the condition of the engine before the overhaul, what is needed for this, what are the terms and guarantee for the repair of the motor.

How to determine the condition of the engine?

The degree of wear of the motor and the cylinder-piston group, in particular, is assessed by measuring compression and residual vacuum, as well as by other technical diagnostic methods (using an endoscope, a motor tester). But there is an indirect indicator - oil consumption. The limit for the engine of a modern car is considered to be the consumption of 1 liter per 1000 kilometers. If more, then there is wear inside the motor.

The mileage of the engine before overhaul varies for different machines within a fairly wide range and depends on the durability of the structure and operating conditions. For many domestic cars, the mileage to the "capital" is on average 150-180 thousand kilometers, the majority of foreign cars - 200 thousand. For example, a BMW engine can run up to 180,000 km before overhaul, Ford - 200,000 km, and many Japanese manufacturers - up to 250,000 km.

What is meant by car mileage before overhaul? This is the mileage above which irreversible consequences occur in the engine in the form of destruction of its parts. For example, gaps appear on the cylinder walls, other parts wear out. After that, the operation of the motor without further repair is impossible. By the way, you can find out the condition of the motor by analyzing the engine oil. If there are metal particles in it and their number increases with mileage, then there is a lot of wear.

The quality and timeliness of maintenance affects the life of the engine. The use of non-original motor oils and bad filters can reduce the resource by dozens of times. In such cases, it is necessary to overhaul the engine even on a new car.

Spare parts selection

The quality of spare parts must be guaranteed Otherwise, all your efforts, time and money will be wasted. It is equally important that the repair does not turn out to be selective: all worn parts and assemblies must be put in order so that later they do not limit the life and reliability of the engine.

As practice shows, domestic motors have their own specifics, and many foreign ones have their own. In stores and markets, you can buy everything for our engines - from the cylinder block to the last bolt and at affordable prices. Unfortunately, the quality of these details can be missed: domestic products sometimes turn out to be outright marriage, and imported ones are a fake for one or another famous company. Therefore, it is not worth making a purchase without experience, it is better to leave this matter to those who will repair the engine.

By the way, respectable workshops never require customers to search for spare parts on their own - they have reliable and trusted suppliers.

With the repair of parts is more difficult: it is not so easy to find a place where machine repairs of the crankshaft or cylinder block will be done with high quality. Lack of special tools and fixtures. There is little literature on repairs, and they don’t read it very much: most craftsmen boil in their own juice, achieving results through trial and error.

What are the deadlines

Do not forget that the overhaul of the motor is one of the most difficult and is not done quickly. Therefore, when choosing a workshop for engine restoration, you should not look for where the repair period is minimal. Some indicative dates are given in the table.

What is the guarantee

When choosing a service station, you should not miss the issue of warranty. Almost everyone gives a guarantee for the work performed, but not everyone correctly understands what it is. A modern engine is a complex mechanical unit with a large number of parts. No matter how well it is repaired, there is always the possibility that some defect will be discovered later.

There is an optimal warranty period. A repaired engine in the initial period of operation is most prone to breakdowns, but after a run of 10-15 thousand km, their probability becomes insignificant. Many service stations define a guarantee with a mileage of 20-40 thousand km, considering that the engine's service life is incomparably longer.

Think engine overhaul is a headache? You think correctly. But when you find out how much they take for work, your head will stop hurting and your hands will start working. Because for that kind of money you can repair three engines. So, we will save money and master the overhaul ourselves.

When does an engine need a major overhaul?

You drove, you drove - suddenly the engine of your favorite iron horse rattled. So do not rush to immediately grab onto the "capital". We need to check everything first.

First, let's immediately determine that this is not a bulkhead of the engine, when it was disassembled, cleaned, gaskets changed and assembled. There are more serious reasons here. So let's take a look at the prerequisites:

How old is the car? How far has she run? Foreign or domestic? If the car is more than 10 years old, it is domestic, for example, a Zhiguli or Moskvich, then its limit is 150 thousand kilometers. For a foreign car - up to 300. Perhaps the resource of your car has been exhausted, and for this reason the power has decreased.
Let's see what's up with the oil. Yeah, the pressure has dropped again, despite the fact that the car bursts oil godlessly - another reason for repairs.
We check the compression, because this is the main parameter that affects the choice - whether or not a major overhaul is needed. We take a compression meter from friends, we take measurements. For example, in our case, out of four indicators, one has five instead of eight, which means that it’s definitely time for a major overhaul.

Where to begin?

Of course, with information. We get a manual in which it is reported in detail and with diagrams how to repair your brand of car. We find a catalog on the Internet that contains spare parts for this car in order to immediately determine the prices and, possibly, place an order in an online store.

Cooking tools:

keys - ratchet, torque;
mandrels for coupling pistons, caps;
rassuharivatel to valves;
micrometer;
heads;
valve adjuster;
two-arm or three-arm puller;
stethoscope;
tweezers;
support stand;
hydraulic chain hoist;
puller kit.

Getting to the engine

We drive the car into the garage. We remove the battery. Detach the hood so that it does not interfere.

Carefully drain all liquids: antifreeze, oil. To do this, instead of bolts on the radiator and cylinder block, we install faucets - they are sold at any auto shop - and drain them using hoses into the prepared container.

Given the age of the machine, we very carefully disconnect the wiring, connectors, pipes, hoses, etc., so that they do not crumble in our hands, nothing is damaged or broken. And then some craftsmen then still repair wiring, cooling system.

We remove without haste everything that can interfere with getting the engine: air filter, carburetor, gasoline pump - do not forget to wind the bolt, oil separator, distributor, cylinder block cover, camshaft, cylinder head studs, and then the head block, crankcase protection, generator with belt, fan, radiator. We unscrew the bolts that secure the engine. Now the engine can be removed.

Stages of engine overhaul on the example of the Zhiguli brand

Step #1

Before you get to the innards of the engine and start doing a major overhaul, try to safely remove it from the car. Call an assistant - one cannot manage here.

Prepare four tires by stacking them on top of each other. Place two wooden blocks on top. Then lay the engine on them.

Step #2

Now fix the talc, i.e. the lift, on the ceiling beam, it can be attached to the tripod, placed above the hood.

Do you know how much the engine weighs? How do you like an aggregate of 140 kilograms? Serious thing? It is clear that you can’t lift it with your hands, and if it falls down, you can’t do without injury. To prevent this from happening, be extremely careful, check the fastening of the talc, and only after that start lifting.

Step #3

Gently, without too much fuss, pull the engine up, bring it to the stack of tires that have already been laid out in front of the car, lower it, turn it over so that the crankcase is on top, on wooden blocks.

When disassembling, remember or mark somewhere where you are shooting from and where the part was originally located, so that later you don’t have extra ones, like some homemade ones.

Start gutting the flywheel: first remove the clutch, then get to the boot of the crankcase. Move on to the oil filter. Having unscrewed the fasteners, remove the bolts and remove the crankcase, being careful not to break the oil intake.

Step #4

Now remove the front and rear covers of the unit along with the stuffing box. Take care of the piglet's star, remove it using a puller. Go to the chain stop and unscrew, remove the tensioner shoe, and then the chain, crankshaft sprocket.

Move on to the crankshaft. Remove the nuts from the connecting rod caps, then the caps, carefully pull out the pistons, remove the liners, carefully inspect them for reuse. If you can no longer use them, take a sample and buy new ones at a specialized store or car market. Just first decide if you need a groove for the necks, and only then fit the liners under them. Get the crankshaft with persistent half rings.

Step #5

Remove the pig, the oil pump and its drive gear. Turn over, putting it sideways, remove the pistons with connecting rods from the cylinders. Buy a new piston system according to the old model. You still need to go to the auto repair shop.

Take new pistons, let them bore the block under them, and also grind the crankshaft and press in the piston pins. Measure the crankshaft journals with a micrometer, look in the manual for what size liners should have, buy them. If you choose the liners correctly, you can rotate the crankshaft by hand This will be the fit test.

Step #6

Start assembly by removing carbon deposits. Remove all metal shavings, wash the beds, lubricate them and liners with engine oil, install in place, guided by the manual. On the rear wall of the block, place the thrust half rings so that the recesses are turned on the plane of the crankshaft.

Now you can return the crankshaft with liners and covers to its place, checking the markings according to the manual, the places where the locks are located. Make sure they are all on the same side. Take a torque wrench, tighten the bolts, turn the crankshaft - if it turns easily, then everything is in order. Otherwise, replace the earbuds with thinner ones.

Step #7

Ask the workshop to assemble the piston, because you yourself will not be able to heat the connecting rod heads to more than 100 degrees, but you need to heat them up to over 200. Check the process.

Now carefully smear the piston pins through the holes, throw in the piston rings without haste, make sure that the slots and holes are preserved, tighten the mandrel with a key. Lay the block on its side, insert the piston with the connecting rod, not forgetting the markings.

Step #8

Take a wooden block and, gently knocking, push the piston into the cylinder. Turn the block back to its original position, but do it so that the crankshaft is at the top. Tighten the bolts.

Gently begin to pull the connecting rods to the necks. Then scroll the crankshaft to make sure that everything is set correctly and the liners do not need to be changed. Now you can tighten the bolts.

Step #9

Put a new oil seal on the cover, install it on the block, pre-lubricate the joints with sealant. Proceed to install the clutch boot and flywheel. Remember that the flywheel must be turned to the fourth knee of the crankshaft with a groove - this is important.

Now start installing the sprocket, pig, tensioner shoe, front oil seal, oil pump, flywheel clutch.

Step #10

You can finally install the engine and bolt it on. Tighten carefully so as not to strip the threads and do not burst parts. Return the pump, generator, radiator, fuel pump to their original places, attach wires, hoses, terminals, check the fastening strength.

Cold running

Once the overhaul of the engine is completed, it is imperative to carry out a cold break-in before installing it on the machine. This is done so that the new parts get used to each other, and is carried out in a passive, bench mode. or in hard towing, when due to the movement of the wheels the crankshaft begins to spin and a cold break-in occurs.

So, in the garage, connect the air filter hoses, cooling systems, oil supply, exhaust to the engine. Install plugs. Connect the unit to the electric motor.

Fill in the coolant that was drained during disassembly, heating it to 85 degrees, then oil heated to 80 degrees. At low speeds, from 600 to 1000, let the engine run for 2 minutes, at high speeds, from 1200 to 1400, for 5 minutes.

Tips for operating the engine after a major overhaul

Before the car runs two and a half thousand kilometers, do not accelerate sharply, pick up speed gradually, do not overload the engine.
After the first run, drain the oil, replacing it with a clean one, but of the same brand (preferably).

Now you are convinced that a do-it-yourself engine overhaul is possible and profitable, because it costs three times less. In addition, it will allow you to operate the car for several more years as a result of extending the service life, prevent unexpected breakdowns on the road, and help avoid an accident.

The following video will tell you about what spare parts are needed for the overhaul of the VAZ 2103 engine:

Take it, tell your friends!