DIY gas 51 engine repair

The engine needs to be repaired only when needed. However, to increase the time between major overhauls, it is necessary to prophylactically change the piston rings and crankshaft bearing shells after 35,000-40,000 km of run. With such a change of piston rings and bearing shells, the service life of the engine cylinders and the crankshaft journals is significantly increased. The liners should be changed not because they have already worn out, but because of the ingress of a significant amount of solid particles into the babbitt layer of the liner, which quickly wear out the surface of the shaft journals. Changing the rings prevents an increase in the amount of gases escaping into the crankcase and reduces cylinder wear. After replacing the piston rings and liners, the engine must be run in in compliance with all the rules given in the chapter "Running in a new car".

Do not disassemble the engine unnecessarily. Excessive disassembly leads to a violation of the relative position of the worn-in surfaces of the parts and to an increase in wear.
When repairing the M-20 engine, many replaceable parts of the GAZ-51 engine are used (see below).

For a slight increase in radial clearances in individual bearings, it is allowed in exceptional cases (when regrinding of the journal to obtain a proper clearance for some reason is impossible or very difficult), the use of shims made of brass foil. In this case, the gaskets must be clamped not only between the cover and the bearing, but also between the liners. This achieves a snug fit of the liners to the bed, which is necessary for good heat dissipation and to prevent the liners from moving in their bed.

When installing the shells of the main and connecting rod bearings, the covers must not be interchanged. Main bearing caps are machined assembled with a block, and connecting rod caps - assembled with connecting rods; therefore the bearing caps are not interchangeable.
When replacing the front main bearing cover, it is necessary to ensure that the cover is not displaced in the direction of the crankshaft axis (due to the gaps between the bolts of its fastening and the holes for them) and that there are no ledges on the bearing surfaces for washers 5 and 4 ( see Fig. 32).
* Detailed information on engine repair is given in the book by G. Schneider “Repair of engines of GAZ-51 and M-20 vehicles”, Gorky Regional Publishing House, 1954.

The book describes the design and repair features of engines for GAZ-51, FA3-63, ZIM, M-20 ("Pobeda") and GAZ-69.

For all the main parts of the engines, information is given on materials, heat treatment, tolerances and fit, wear, repair dimensions, repair methods and equipment used in this.

The book can also be used as a guide for the repair of various modifications of the GAZ-51 and M-20 engines installed on special-purpose vehicles and vehicles: dump trucks, buses, firemen, ambulances, forklifts, etc.

Spare parts for Lviv autoloaders AP-40814, 4014, 4045 with the GAZ-52 engine. Spare parts for loaders LZA AP-4081, 40810, AP-41015, AP-41030 Lev with diesel D-243. Spare parts for lift trucks AP-40811, 40816 with D-144 internal combustion engine.

The pistons of the GAZ-51, GAZ-52 engine of the Lviv loaders AP-4014, 40814, 4045, 4043 are made of heat-treated aluminum alloy. The bottom of the piston is flat, the skirt is oval, obtained by grinding the piston on a copy. The major axis of the oval is located in a plane perpendicular to the axis of the piston pin, i.e., in the plane of action of lateral forces on the piston. The ovality value is 0.29 + 0.05 mm.

To make the piston skirt springy, a U-shaped slot is made in it. The oval shape and the U-shaped slot make it possible to select the GAZ-51, GAZ-52 pistons to the cylinders with a minimum clearance in the direction of the lateral forces acting on the piston (perpendicular to the piston pin axis) and a significantly larger clearance in the direction in which there are no lateral forces (parallel to the axis piston pin).

This reduces the noisy operation of the pistons of an unheated engine, and also eliminates the possibility of piston scuffing when the engine is running at full load.

The latter is explained by the fact that when the piston GAZ-51, GAZ-52 is heated, due to the oval shape of the skirt and the U-shaped slot, the expansion of the piston skirt in different radial directions is not the same: along the axis of the piston pin, the piston expands more than in the direction perpendicular to the axis of the piston pin.

As a result, the piston skirt after heating becomes almost cylindrical, and the size of the gaps between it and the cylinder in different radial directions is leveled.

On the piston head of GAZ-51, GAZ-52, five annular grooves are machined: the upper one is the narrowest one - to reduce heat transfer from the piston bottom to the upper compression ring and, thus, to reduce the temperature regime of this ring; compression rings are installed in the second and third grooves, oil scraper rings in the two lower ones.

In the grooves for the oil scraper rings, holes are drilled through which the oil removed by the oil scraper rings from the cylinder bore is diverted into the piston cavity and from there
- into the crankcase.

Clogging or clogging of these holes with carbon or tarry deposits leads to a sharp increase in oil consumption, since in this case a large amount of it penetrates
into the space above the piston and burns in it.

In the middle part of the piston GAZ-51, GAZ-52 of Lviv forklift trucks AP-4014, 40814, 4045, 4043 there are two bosses with holes for the piston pin. Annular grooves (one in each boss) are machined inside the bosses at the outer ends, intended for the installation of retaining rings in them.

The diameter of the bore for the piston pin in the piston bore is 22 mm.

Below the lugs inside the piston, there are two lugs for adjusting the pistons by weight. Standard piston weight 450 ± 2 g.

To improve the running-in to the cylinders, the GAZ-51, GAZ-52 pistons are subjected to contact tinning after final machining. The thickness of the half-layer is 0.004-0.006 mm.

The pistons are installed in the engine so that the U-shaped slot on the skirt faces the opposite direction to the valves.

Piston rings of the GAZ-51, GAZ-52 engine

There are four piston rings: two compression rings and two oil scraper rings. All rings are located above the piston pin.

Each ring is made from an individual non-circular cast iron casting, which provides a fine-grained, wear-resistant cast iron structure, and their non-circular shape - an uneven distribution of ring pressure on the cylinder walls (with a gradual increase in pressure to the lock). All rings have a straight lock.

The low height of the GAZ-51, GAZ-52 compression rings and their high elasticity, as well as the uneven distribution of pressure on the cylinder walls, ensure good tightness of the rings when the engine is running at all crankshaft revolutions.

Due to the fact that the upper compression ring works in more severe conditions and therefore wears out faster than the rest of the rings, its outer cylindrical surface is subjected to porous chromium plating, which increases the wear resistance of the ring by 3-4 times.

The total thickness of the chromium layer is 0.10-0.15 mm, the thickness of the porous chromium is 0.04-0.06 mm. As a result of the porous chrome plating of the upper compression ring, the wear resistance of the other three piston rings and cylinders also slightly increases. Thus, the life of the rings before replacing them with new ones is significantly increased.

The outer cylindrical surface of the second compression ring and both oil scraper piston rings GAZ-51, GAZ-52 are subjected to
electrolytic tinning. The thickness of the coating layer is 0.005—0.010 mm.

Piston rings must simultaneously perform three functions:

- ensure the tightness of the cylinder (do not let gases from the cylinder into the crankcase);

- distribute the oil film over the cylinder mirror and prevent oil from entering the combustion chambers;

- transfer heat from the piston head to the cylinder walls.

The rings can perform these functions only when they fit tightly to the cylinder mirror around their circumference and exert a certain pressure on it.

Loss of elasticity by the rings and clogging of sipes in the oil scraper rings with carbon or resinous deposits lead to a sharp increase in oil consumption and to a decrease in engine power. Deterioration of the tightness of the rings is detected when the engine is running by the increased passage of gases into the crankcase.

Leaking gases and increased oil consumption are a sign of wear on the piston rings and the reason for their replacement.

Piston pins GAZ-51, GAZ-52

Piston pins of the GAZ-51, GAZ-52 engine of Lviv loaders AP-4014, 40814, 4045, 4043 of floating type, hollow. They are made of steel grade 45. The outer surface of the fingers is hardened by high-frequency currents to a depth of 1-1.5 mm to a hardness of HRc = 58-65.

The outer diameter of the piston pin is 22 mm, the inner diameter is 14.8 mm, and the length is 70 ± 0.1 mm.

The piston pin, held by two retaining rings only against axial movements, during engine operation has the ability to rotate freely in the piston bosses and in the upper connecting rod head; therefore, the piston pin wears only slightly and evenly over its entire length.

To prevent the knocking of the piston fingers of GAZ-51, GAZ-52, which perceive large dynamic loads during operation, they are matched to the pistons and connecting rods with the minimum clearances necessary to ensure normal lubrication.

In this case, it is taken into account that the clearance between the piston and the pin during operation (i.e., when heated) increases due to the greater coefficient of expansion of the aluminum alloy (from which the piston is made) compared to steel (from which the pin is made).

Therefore, the diameter of the holes for the piston pin of the GAZ-51, GAZ-52 engines in the piston is made somewhat smaller than the diameter of the pin itself. Therefore, at normal room temperature, the finger sits in the piston not with a gap, but with a slight interference, which disappears when the piston heats up (in working condition) and a gap appears instead.

Retaining rings of the piston pin of engines manufactured before 1955 were made of steel tape. However, in connection with. insufficient reliability of their work (breakage near the ears, pushing out of the grooves by the piston pin), which led to the seizure of the cylinder mirror, the plant since 1955 switched to the manufacture of wire retaining rings with antennae slightly bent to the side.

These rings have a deeper and therefore more secure fit in the piston grooves than flat rings. Install them in the grooves so that the bent antennae are facing outward. Wire and flat retaining rings are not interchangeable.

Connecting rods GAZ-51, GAZ-52

The connecting rods of the GAZ-51, GAZ-52 engines of Lviv forklift trucks AP-4014, 40814, 4045, 4043 are steel, forged, I-section. The lower connecting rod heads are asymmetrical with respect to the connecting rod rod and the upper connecting rod head (offset by 3 mm). The short shoulder of the lower head of the connecting rods of the first, third and fifth cylinders is directed towards the front end of the block, and the second, fourth and sixth cylinders - towards the rear.

1. Connecting rods of the GAZ-51, GAZ-52 engine

a - for the first, third and fifth cylinders; b - for the second, fourth and sixth cylinders.

The lower head cover is attached to the connecting rod GAZ-51, GAZ-52 by two ground bolts with nuts, each cotter-pinned separately.The plane of the connector of the cover and the connecting rod runs along the diameter of the hole for the bushings (perpendicular to the connecting rod axis).

The exact relative position of the cap and the connecting rod is ensured by the ground cylindrical part of the connecting rod bolts, which have a sliding fit in the holes in the cap and connecting rod.

The hole for the bushings in the lower head of the connecting rod is machined together with a cover. Therefore, in order to avoid violation of the achieved accuracy of the holes for the inserts, rearrange
caps from one connecting rod to another are not allowed.

To exclude the possibility of incorrect assembly of GAZ-51, GAZ-52 connecting rods with covers during engine repair, a number corresponding to the cylinder number is stamped on the lower head of each connecting rod and on its cover when assembling engines at the factory.

When assembling, make sure that the indicated numbers on the cover and on the connecting rod head are the same and are located on the same side.

If a new connecting rod is installed on the engine during repair, the corresponding number should be put on the connecting rod and cap before removing the cap. This will eliminate the possibility of error during the subsequent assembly of the connecting rod.

With the correct relative position of the cover and the connecting rod, the sockets in them for the fixing protrusions of the liners are located on one side (at the same joint).

The lower heads of the connecting rods GAZ-51, GAZ-52 are equipped with thin-walled interchangeable steel-babbit inserts.

Thin-walled (1 mm thick) bushings rolled from tin bronze grade OTsS 4-4-2.5 are pressed into the upper heads of the connecting rods. After pressing in, the sleeves are deployed to
diameter 22+ mm.

To lubricate the piston pin, there is a cutout in the upper head of the connecting rod, and a round hole in the sleeve that coincides with it.

In the place where the lower head passes into the rod, a hole with a diameter of 1.5 mm is made, through which, once for each revolution of the crankshaft (when the hole coincides with the oil channel in the crankshaft), an oil jet is thrown out, lubricating the cylinder walls.

The finished connecting rods, assembled with caps, are factory adjusted to weight to ensure engine balance. The total weight of the connecting rod and the distribution of weight between its heads are adjusted by partially cutting off the boss on the top head and a lug on the bottom head cover. Fitting accuracy of both heads ± 2 g.

All connecting rods GAZ-51, GAZ-52 are divided by weight into the following four groups:

Lower head weight (g) Upper head weight (g) Marking color

The color marking of the weight group is applied to the cut surface of the cover of the lower connecting rod head.

GAZ-51, GAZ-52 connecting rods of only one weight group are installed in one engine. The difference in the weight of the connecting rods of one engine should not exceed 8 g, and the difference in the weight of the sets, which consist of connecting rods, assembled with pistons, pins and rings - 14 g. This must be remembered when replacing the connecting rods during engine repair.

Pistons and connecting rods 52-1004 (auto-loader AP-4014, 40814, 4045, 4043)

Piston and connecting rod assembly of the first, third and fifth cylinders 52-1004010-A2

Piston and connecting rod assembly of the second, fourth and sixth cylinders 52-1004011-A2

1 - Piston assembly of nominal size VK52-1004014-A

Piston assembly O82.50 mm VK52-1004014-EP1

Piston assembly O83.00 mm VK52-1004014-LR1

2 - Piston assembly O83.50 mm VK52-1004014-NR1

Piston assembly O84.00 mm VK52-1004014-PR1

4 - Piston pin 11-6135-A2

5 - Retaining ring 12-1004022-B

6 - The connecting rod assembly of the first, third and fifth cylinders 51-1004045-01

Connecting rod assy of the second, fourth and sixth cylinders 51-1004046-01

7 - Connecting rod bushing 12-1004052-A

7 - Connecting rod bushing 12-1004052-A

8 - the Bolt of the connecting rod 13-1004062-B

10 - Lock nut 292759-P

Spare parts are shipped to Lviv loaders 4014, 40814, 40810, 4081, 41030 to all cities of Russia: Kemerovo, Yekaterinburg, Chelyabinsk, Novosibirsk, Ulan-Ude, Kirov, Perm, Krasnoyarsk, Irkutsk, Omsk, Barnaul, Tomsk, Bratsk, Tyumen, Lysva, Novokuznetsk, Miass, Serov, Chita, Berezovsky, Mezhdurechensk, Nizhny Tagil, Biysk, Minusinsk, Satka,Kurgan, Vologda, Nizhny Novgorod, St. Petersburg, Belgorod, Oryol, Kazan, Rostov-on-Don, Voronezh, Bryansk, Krasnodar, Saratov, Murmansk, Tula, Noginsk, Volgograd, Ivanovo, Penza, Cheboksary, Volzhsky, Yaroslavl, Syktyvkar , Izhevsk, Samara, Makhachkala, Volzhsk, Yoshkar-Ola, Sokol, Ufa, Arkhangelsk, Tver, Podolsk, Ulyanovsk, Smolensk, Togliatti, Vladikavkaz, Petrozavodsk, Kursk, Vladimir, Cherepovets, Naberezhnye Chelny, etc.

GAZ 52 is a car of an entire era. The engine of this vehicle can be said to be a crossover model between 53 and 51 Lawns. As practice has shown, the power unit is quite reliable, but more and more often the remaining motors are being overhauled.

The Gas 52 engine has fairly high technical characteristics. The cars were equipped with a 6-cylinder in-line engine, which significantly distinguished them from other engine models.... So, let's consider the main technical characteristics and the device possessed by the power units:

Do-it-yourself overhaul of the GAZ 52 engine is quite typical, as for the rest of 6-row engines. As practice shows, most motorists do it on their own, since the cost of restoration is quite expensive.

At the beginning of the repair, the motor is disassembled, which is typical for the restoration operation. The piston group is disassembled, the crankshaft is pulled out, the cylinder head is removed. The next step is to carry out diagnostic work.

In the process of diagnostics, the internal combustion engine Gas 52 is subjected to measurements. So, the piston group is measured, as well as the crankshaft. Accordingly, the motor is inspected for cracks. According to the measurements, the GAZ 52 engine, which is being repaired, is the selection of pistons. The main overhaul dimensions are pistons - 82.5mm, 83mm. In the future, there is no point in boring, and the block sleeve is being carried out.

As for the crankshaft, it is bored on a special machine for grooving crankshafts. So, the typical repair dimensions that are installed on the necks are 0.25 mm, 0.50 mm and 0.75 mm. In very rare cases, the size marked with 1.00 mm is used. This dimension of the crankshaft journals significantly reduces the hardness, which is likely to lead to a break in the engine heart and other consequences.

The boring of GAZ 52 (engine) must be carried out by professionals and very accurately. So, the power unit is installed on a special stand on which the cylinders are sharpened. If before this, the block liner was carried out, then it is still necessary to grind the liners and adjust the pistons along the clearances.

Also, so that there is no imbalance, the piston group is adjusted by weight. So, pistons and connecting rods (more precisely, bushings) are adjusted by weight using the groove method.

The next stage is honing. Each cylinder is honed to a mirror finish. This is necessary in order for combustion to occur correctly, and the pistons with oil scraper rings slide and completely remove oil from the walls.

After these operations, the motor is placed on a surface grinder and the surface is sanded. So, it is removed from 1 to 5 millimeters until the surface is flat. The next step will be washing to clear the entire inner world of the engine from shavings and dust.

The assembly process is quite long. First, the piston group is tied up, or rather the crankshaft is laid, and connecting rods with pistons are attached to it. Further, the cylinder head is overhauled. So, guide bushings, valves, valve seats are changing (with a strong block resolution at the valve attachment points). If necessary, the cylinder head is pressurized and cracks are repaired. This is done using argon welding.

Further, the motor begins to collect. During the assembly process, the water pump is diagnosed. If necessary, the shaft assembly, bearing and impeller are changed on it.The pump is one of the last elements to be installed. Subsequently, the pallet and the block head are placed. When everything is assembled, oil is poured into the motor. For the GAZ 52 engine, this is 10 liters of lubricant - M-8.

The last step is rightfully running in and adjusting the valves. So, this power unit first rolls on a cold one, and then on a hot one. After running 1000 km, it is worth carrying out maintenance to change the oil, oil filter and adjust the valve mechanism.

Most motorists prefer to repair their GAZ 52 engine themselves, neglecting the technical repair cards and processes. So, a car engine must go through all the stages of overhaul, and only after that, it is guaranteed reliable and long-term operation.

I dreamed of having my own GAZ-51 for a long time. My father worked on this, first on a collective farm, and then in a driving school. I told my parent about the idea to restore the car with my own hands, but did not receive approval: “Why do you need such a truck - we already have a GAZelle. If you want an old car, let's put together a Gazik, I dreamed about it when I was young. " So I got a disassembled GAZ-69, its assembly to a running state took several years. But I didn’t give up the dream of GAZ-51.

Since the GAZ-51 and GAZ-69 are similar and unified, during the assembly of the "bobby" I came across spare parts and "half a hundred and first", and sometimes I did not even know about it. For example, I became the owner of brand new fenders and a dashboard for this truck. Along the way, it became clear where the skeletons of the "lawns" were. At one point, at a local pensioner, I came across an almost complete GAZ-51A semi-garage storage - the cab and part of the body on the rear axle in the garage, the rest on the street. For a while, I forgot about it, until I was told that the car has a real chance of being in the scrap metal. There was no time to think, and after a short dispute with the owner, he sold me a truck for 3000 rubles. “The car is good. Body floor - metal. You will repair, you will drive! " - the old man admonished.

It happened 5 years ago, and the car itself cooled down in 1995 and, thanks to the earthen floor of the garage, has already grown into the ground. The owner said that the wiring was faulty - the rats were gnawing, therefore, it was not worth trying to start the engine, so they tried to pull it out into the light of day with a tractor for 20 minutes. At the same time, everything that even remotely resembled spare parts was collected in the garage and yard. Attempts were crowned with success, and the "51st" on a cable, without brakes (even the indestructible handbrake did not work!) Set off. In the course of a short haul, it turned out that the gearbox is still working and the gears are not popping out.

I say hello to those who like to remove the nameplates (nameplates) from old cars. Dear patrons> and my plates are not with you for an hour?

I would like to ask readers about missing original parts. Looking for:

1. Diffuser.
2. Carburetor (only new!).
3. Stamped plate for collecting gasoline under the carburetor.
4. Driver's seat.
5. Gas pedal.
6. Wiper arms with brushes and mounting bolts (female thread).
7. Battery box and cover.
8. Windshield frame with elastic band (only new or very well preserved).
9. Elastic band (round) on the starter pedal.
10. Rear wheel guards and oil canister for right guard.
11. Book or catalog of parts for GAZ-51 or GAZ-63.
12. Driver's tools and accessories that came with the car.
13. Driver's half of the seat.
14. Other original details that you did not see in the photographs and I do not know about them.

Since everyone here loves straight-sixs, I found an interesting article on bringing to mind the most balanced engine! We are discussing!

It has long been the custom that the GAZ 51 - 52 engine is considered weak and unreliable. Its main drawback is weak connecting rod bushings. Any driver knows - you set the truck to its maximum speed - 70 km per hour - and you can immediately go to the minder.I, being the owner, also faced this filth.

Why is this happening? Nobody knows the exact answer. Some say that the engine, de, old, was designed before the war, and was not designed for high speeds. Others look for the reason in asymmetric connecting rods, others blame the assembly of poor quality and useless oils, advanced ones indicate a long piston stroke - that's, they say, where the dog is buried - centrifugal force destroys the liners at high speeds. The grand total: rubbish is a motor! It’s just that - the GAZ 53 engine!

For 5 years of daily operation, I have repaired the engine 6 times. Honestly, butted! Naturally, all this time I was tormented by the thought of why this was happening. I tried everything. The motor was repaired by cool specialists, and not very much, later I learned it myself, but the result is the same - the liners fly!

I began to reason logically. Old motor design? Nonsense! Not much different from modern ones.
Symmetrical-asymmetrical connecting rods differ by millimeters from each other - there can be no problem here.
Excellent assembly of the motor does not guarantee its reliable operation, it means that the matter is in something else. What is it? Perhaps, it is true, the matter is in the long piston stroke - 110 millimeters? But what about diesels then? Their design feature is precisely the long piston stroke, both 120 and 160 millimeters, and nothing - they work great.
When I started comparing the GAZ 52 engine with others, for example, with the Zhigulevsky one, some details caught my eye - the connecting rod journals of the GAZ 52 crankshaft have one hole for supplying lubricant, and the Zhigulevsky ones have two! Yeah, so the revving motor needs more lubrication! And others? Is it because the GAZ 52 liners are flying because they lack lubrication?

AND YOU WILL HAVE A HAND BEAST! UNKILLABLE GAS 52!

Think for yourself. The connecting rod journals of a long-stroke motor experience a huge centrifugal load, and are lubricated with ONE hole. The oil channels cut in the liner allow continuous supply of oil under pressure to the entire surface of the liner and the shaft journal. In this case, the shaft is practically not lubricated with oil, but simply hovers in oil above the surface of the liner.

AND EVERYTHING. From that moment on, the main problem of the GAZ 52 engine disappeared. He became indestructible! The next 5 years of daily operation in hot and cold weather, on highways and in the mountains showed that the engine is in no way inferior to the most modern units! The former “ugly duckling” easily tolerates speeds over 120 km. Can you imagine? The GAZ 52 engine runs without problems for a long time at maximum speed!

My own achievement did not even make me happy, but puzzled. The eternal problem, it turns out, can be solved so easily! No engine alterations, just refining the liners!
Seeing how thousands of trucks are endlessly idle in repairs, what did the designers of GAZ think about? This is now the main mystery for me.

Another "invention" (just don't fall off your chair!) Is the installation of the block head WITHOUT GASKET. The fact is that the cylinders of the GAZ 52 engine are so close to each other that sometimes their gasket "breaks through" in these places. The block and the cylinder head are cooled with water, and the gasket at a constant operating temperature of 2000 degrees between the cylinders simply burns out. I "put" the head of the block on thermal paste, its name, alas, I do not know. It is better to install the block head from a gas-powered engine with a compression ratio of 7.2. Exhaust valves with sodium filler from GAZ 53, they are heat-resistant, but thicker, you just need to expand the valve sleeves from 8 to 11 millimeters. They “run” on any gasoline, including “Extra”.

All these changes are also applicable to the GAZ 69 and M 20 Pobeda engines.

And, of course, the engine oil is ONLY SYNTHETIC! Feel the difference, as they say! Go broke a little and fill up after a simple "synthetics" no higher than 5/15, and you will understand why all these vaunted motors of fashionable wheelbarrows give out their "horses"!
In general, after these simple manipulations, the motor magically changed. Work became quiet and stable.The maximum number of revolutions and the power have clearly increased so that no eight-cylinder GAZ 53 is needed. After such modifications, the engine “dashed off” 200 thousand km without any problems. Maybe I would have dashed off more, but I sold my ZIM and I don't know anything about its further fate.

The GAZ 52 engine is the simplest, cheapest and most reliable unit today! Think for yourself: the block is very stable - cast iron, the sleeves are not flimsy "wet", but pressed in. There are no chains, rods, tensioners, dampers, balancers, rollers, etc. woof * oh!

Obviously, the race for rpm and economy makes modern motors simply inoperative. I think it's too early to write off the GAZ 52 engine for scrap, it can (and better than others!) Work on cars, boats, forklifts, etc. Especially in the private sector, where there is no way to throw money on expensive repairs. And you need a little spare parts for it and it is not difficult to get them. It is a pity that the tycoons of the automotive industry do not understand such obvious advantages of the old reliable technology.

And the main thing. With a thoughtful assembly, the GAS 52 ENGINE IS UNKILLABLE!

Zyclone, Silverbag and Photon comments are welcome!

Adherence to a certain sequence of operations for assembling engines contributes to significant time savings and an increase in the quality of their repair. Below, as an example, the procedure for assembling the GAZ-51 engine is given, which is mainly characteristic of the ZIM-12, M-20 and GAZ-69 engines.

1. Install the block on the stand with the crankcase side down, select the pistons to the cylinders and assemble the connecting rod-piston group, as indicated in the sections: "Change of pistons and their repair" and "Subassembly of the connecting rod-piston group" of Chapter III.

2. Screw in all the pins, plugs and put the dowel pins in place, if they were removed from it during the repair of the cylinder block. It is also necessary to press the oil filler pipe and the oil level indicator tube into the block.

3. Reinstall the valves, having greased their rods with oil. To lubricate the rods, use machine oil "SU", autol 6 or better castor oil.

At repair enterprises, it is recommended to use a special lubricant for this purpose, consisting by weight of 70% of an oil colloidal-graphite preparation of the MP brand (GOST 5262-50) and 30% of MS-20 or MS-14 oil, mixed at normal room temperature until a homogeneous state and the absence of lumps. The specified grease must be mixed thoroughly each time before use. The use of this grease protects the friction surfaces of valve stems and guide bushings from scuffing during their running-in.

4. Replace the valve springs, valve plates and crackers. It must be remembered that the valve springs should be placed upside down with a reduced pitch.

5. Raise the valves to the point of failure and place shims under their heads, which, during further assembly, hold them in the raised position.

6. Turn the block 180 ° - with the crankcase part up.

7. Remove the rear main bearing cover and screw the halves of the oil seal holder with oil seals to the block and to the cover. Pressurize the rear main bearing oil seal,

as indicated in the section "Changing the front and rear crankshaft oil seals" in Chapter III.

8. Remove the main bearing caps, blow out the bushings in the block and caps with compressed air, as well as the groove for the crankshaft oil relief collar in the rear main bearing. Replace the main bearing shells.

Insert shaped rubber seals into the slots in the rear main bearing cover.

9. Wipe the main journals of the crankshaft with a clean rag, lubricate them with oil and put the rear thrust bearing washer on the first main journal; the babbitted side of the washer should be facing the cheek and oiled. Place the crankshaft complete with flywheel and clutch in the main bearings.

10.Put the main bearing caps in their places and bolt them to the block. At the same time, check the diametral clearances in the main bearings using one of the methods specified in the section "Replacing the crankshaft main and connecting rod bearings". Perform final tightening of the main bearing bolts with a torque controlled wrench (see above section "General instructions for disassembling and assembling motors"). Before screwing on the rear main bearing cap, you must install a striker plate on it. After the final tightening of the covers, split the bolts of their fastening, as shown in Fig. 157; Bend the tabs of the locking plate of the rear main bearing to the edges of the bolt heads.

11. Carefully wipe the beds of the liners in the lower heads of the connecting rods with a clean rag and remove the covers from them. Put on the connecting rod bolts special cast iron or copper lugs that protect the cylinders from scratching when installing assembled sets of pistons with connecting rods in them.

Check if the lubrication hole for cylinders, camshaft cams and tappets in the lower connecting rod head is open. Put the connecting rod bearings in their places.

12. Rotate the block 90 ° - with the front plane up.

13. Wipe with a clean cloth and oil the cylinders. Insert the assembled sets of pistons with connecting rods into the cylinders, according to selection and numbering.

14. Wipe the connecting rod journals with a clean cloth and lubricate them with oil.

Sequentially tighten the lower connecting rod heads to the connecting rod journals. Remove the end caps from the connecting rod bolts and replace the connecting rod caps. Check the diametral clearances in the connecting rod bearings at the same time. Finish tighten the connecting rod bolt nuts with a torque controlled wrench.

Cotter the nuts, turning them, if necessary, in the direction of tightening increases until the nearest slot on the nut coincides with the hole for the cotter pin in the bolt.

15. Replace the front crankcase-engine seal bracket so that its front end coincides with the end of the block. The bracket is placed on two gaskets, pre-lubricated with shellac or "UN-25" paste.

16. Put on the dowel pins the timing gear cover plate with the gasket and screw it to the block with four bolts and one nut (Fig. 158)

17. Replace the timing gear lubrication tube, securing it with a clamp, bolt and washer. Before installation, the tube must be thoroughly cleaned and blown out with compressed air from the side of the calibrated hole.

18. Rotate the block by 80 ° - with the crankcase part up.

19. In the bore of the front end of the block, put the front thrust bearing washer on two pins and put the thrust ring on the front end of the crankshaft. Check the axial clearance of the crankshaft. The check should be done as follows:

a) insert the end of a screwdriver between the last elbow of the shaft and the inner wall of the rear end of the block and press the shaft towards the rear washer of the thrust bearing. In this case, the protrusion on the rear washer must fit into the corresponding groove on the thrust bearing cover;

b) press the crankshaft thrust ring to the front end of the first main journal;

c) determine the size of the gap with a feeler gauge placed at several points around the circumference between the ends of the front thrust washer and the thrust ring.

If necessary, adjust the clearance as described in the section "Repairing the crankshaft thrust bearing" in Chapter III.

20. Press the camshaft onto the front end of the crankshaft with the key in place.

21. Select and install the pushers in the block, as indicated in the section "Change of pushers and repair of their guides in the block", Chapter III.

22.Wipe with a clean cloth and oil the camshaft bearings; wipe the bearing journals of the shaft, previously assembled with a spacer ring, a thrust flange and a timing gear, and put the camshaft in place.

Before installing the shaft, check its axial clearance and, if necessary, adjust it as described in the section "Repairing the camshaft" in Chapter III,

Check with a feeler gauge inserted into the gap between the front end of the shaft journal and the thrust flange; the latter must be firmly pressed against the hub of the timing gear. When installing the camshaft, special attention should be paid to the coincidence of the marks on both camshafts (see Fig. 23).

23. Screw the thrust flange onto the block. The flange must be in direct contact with the plane of the block — without any gaskets. Check the gap in the meshing of the timing gear teeth with a feeler gauge.

24. Rotate the block 180 ° - with the crankcase down.

25. Lower the valves by lifting them and removing the linings from under them; adjust the valve clearances as described below in the section "Adjusting the motors".

26. Reinstall the two valve box covers with gaskets.

27. Install the gas pipeline gaskets and screw the gas pipeline to the block using the special key provided in the driver's tool kit.

28. Wipe the top surface of the block with a clean cloth. Put on the studs the cylinder head gasket and the head assembly with the outlet pipe and the thermostat of the cooling system. Before installing the head on the engine, in order to prevent foreign objects, dust and sand from entering the cylinders during subsequent work, the holes for the candles must be closed with wooden plugs or plugged with clean rags.

29. Install the brackets for the fine filter, oil filler neck and gas pipeline shield.

Screw the nuts onto the studs and tighten them as described above in the section "General instructions for disassembling and assembling motors". Place flat washers under the nuts that are in direct contact with the head.

30. Put the oil deflector on the front end of the crankshaft and press in the parallel key of the crankshaft pulley hub.

31. Install and screw on the camshaft cover with the front oil seal (see section "Replacing the front and rear crankshaft oil seals" in Chapter III).

32. Press on the crankshaft pulley hub assembly with pulleys.

33. Screw on the water pump.

34. Rotate the block 180 ° - crankcase up.

35. Refit and screw on the oil pump as described in section 2 "Lubrication system" in chapter I when describing the oil pump.

36. Assemble the oil sump with gaskets and screw it onto the block.

This, in fact, ends the assembly of the engine itself. Ancillary equipment should be installed on the engine prior to installation on the vehicle.

Adherence to a specific sequence of operations when disassembling an engine is not as essential as when assembling. However, during disassembly, in order to minimize the time required, a certain order must also be followed. The disassembly process for an engine should generally be carried out in the reverse order of assembly.