Dimensions of nominal and repair dimensions of MTZ main and connecting rod bearings (D-240 and D-245) in millimeters

We will be happy to read them and discuss this issue with you.

If the gap is greater than the limit, replace the liners on these journals with new ones. Diameter of the crankshaft journal, mm Width of the fifth main journal, mm main.

Dimensions of the crankshaft journals When replacing bearings, install them of the same rating as the crankshaft journals.

After regrinding the journals or when repairing the engine without grinding the crankshaft, remove the plugs from all connecting rod journals and thoroughly clean the cavities. If, of course, there are no cracks or chips, then just throw the block away.

When regrinding the main and connecting rod journals, it is necessary to maintain the linear dimensions indicated in the table. The size of the parts depends on the rating of the MTZ crankshaft journals.

The tolerance for parallelism of the end surfaces of the crankcases mating with the diesel cylinder block and the gearbox is 0.05 mm over a length of mm.

When grinding the ends of the rear molar journal, the allowance must be removed symmetrically from each end.

In this case, the liners of the previous size are bored to the additional repair size D1, D. When assembling the mechanism, we advise you to thoroughly rinse the liners MTZ 80, 82 and other parts with diesel fuel. Connecting rod bearings (H1) of the crankshaft of the engine D-240, MTZ-80 50-1004140A - #InsertsD240 - #InsertsMTZ

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The holes in the upper halves of the main bearings coincide with the oil supply channels in the block. The condition of the crankshaft bearings and the size of the gaps is characterized by the oil pressure in the main oil line.

Balancing of the crankshaft, as well as the flywheel and clutch installed on it, should be carried out in dynamic mode with weights on the connecting rod journals, replacing the connecting rod and piston group on the connecting rod journal. To do this, rotate the engine crankshaft until the valve is fully open with the thermal clearance set for a cold engine and measure the distance from the end of the valve stem to the head.

Reducing the length of the teeth of the crown without chamfer length is allowed up to 16 mm; the length of the teeth of the new crown is 18 mm. Numbers 0.25; 0.50, etc.

Tightening begins with a long bolt. The outer and inner surfaces of certain diameters and the ends of the load are finally processed after connecting the half rings with bolts.

We will be happy to read them and discuss this issue with you.

Table 2.

In this way, very severe damage to beds and yokes can be corrected. The alignment of the hole along which the gearbox is centered with the crankshaft axis and the perpendicularity of the crankshaft axis are checked after installing the shaft. How to clean the crankshaft after boring. MTZ tractor.

Article on the topic: adjusting the power take-off shaft MTZ-80

How to find out crankshaft sizes

There are special tables where you can find out the crankshaft sizes for a specific car model or equipment. Such tables are available for all types of vehicles and technical vehicles on which an internal combustion engine is installed. The sizes of earbuds available on the market correspond to these sizes.

For example, for the Opel Kadett 1.3S, the standard dimensions of the main journals are 54.972–54.985 mm, when grinding to a depth of 0.25 mm - 54.722 - 54.735 mm, when grinding to a depth of 0.5 mm - 54.472 - 54.485. The dimensions of the connecting rod journals, respectively, are 42.971 - 42.987 in the standard (zero) version, 42.721 - 42.737 with grinding at 0.25 mm and 42.471 - 42.787 with a processing depth of 0.5 mm. For the VAZ-2108 car, the standard diameter will be 50.779–50.819 mm, and there are four repair sizes: 50.549–50.569, 50.229–50.319, 50.049–50.069 and 49.799–49.819.

As a rule, during the first repair the neck is ground to a depth of about 0.25 mm. The following sizes are located at the same distance from each other: 0.5, 0.75 and 1 mm. For some models, steps of 0.125 mm are also possible. The tables allow grinding in two more sizes, 1.25 and 1.5 mm, however, such processing is fraught with destruction of the shaft during operation. For this reason, earbud sizes 1.25 and 1.5 are rarely available in stores. In case of significant wear, they are sometimes reground “through size,” that is, they reduce the diameter by two sizes at once.

Neck sizes for VAZ

Nominal, repair and permissible without repair dimensions of the crankshaft

Unscrew the four nuts 1, having previously bent the edges of the locking plates 2, and remove the flywheel 3, pulling it out from the bottom of the clutch housing. Remove the old packing and insert a new one approximately mm long.

On the neck under the front oil seal it is allowed to install a repair sleeve made in accordance with Fig.

If the surface of the MTZ connecting rod bearings is in good condition without cuts or punctures, inclusions of dust or dirt, pay attention to the bearing and the size of the diametrical clearance. The mass of weights for balancing the crankshaft D, without plugs, with flywheel and clutch assembly for crankpins of nominal and repair sizes is selected in accordance with the recommendations of OGK PA MMZ. Before assembling the piston group associated with the installation of new parts, they are selected according to size groups. Remove the cover of the timing sprockets; to do this, perform the operations specified in 2. Before installing the liner in the block, inspect the condition of the sealing rings and the lower seats for the liner in the cylinder block. Also, do not forget to blow out the elements with compressed air. Dynamic balancing of parts installed on the crankshaft MTZ flywheel, pulley, crankshaft, clutch pressure and driven discs should be carried out on machines mod.

The inner diameter of the lower head of the connecting rod is checked after the control tightening of the connecting rod bolts with a tightening torque of 19 kgf-m. If the valve movement is below the required value, the camshaft should be replaced. A bimetallic bushing 8 is pressed into the upper head of the connecting rod. Tips for installing MTZ liners After replacing defective parts, it is necessary to install new ones.

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The crankshaft (crankshaft) is an important component in the crank mechanism of a car. Its function is to sense the reciprocating motion of the pistons and convert it into torque, thus ensuring smooth engine operation. Structurally, it consists of several main and connecting rod journals connected to each other by cheeks. As wear occurs, the shaft is ground to repair dimensions, which accordingly changes the dimensions of the crankshaft journals. Usually up to 6 repair sizes are provided; Soviet standards allowed 8 for a number of models.

Crankshaft and its device

In the manufacture of the MTZ tractor crankshaft, exclusively high-quality steel is used, subjected to long-term heat treatment and additionally coated with special anti-corrosion materials, which ensures long-term and safe operation of the unit. Considering the design of the crankshaft, it should be noted that the first, fourth, fifth and eighth crankshaft journals have counterweights of a removable configuration. This makes it possible to significantly reduce the centrifugal force coming from the crank masses and not having balancing, and in addition, it extends the service life of the main group bearings. The connecting rod-type crankshaft journals are hollow inside, which allows, provided the plugs are installed, to clean the incoming oil due to the influence of centrifugal force.

The front part of the crankshaft is equipped with timing gears, a drive pulley responsible for operating the water pump, and an oil pump drive gear. The rear flange of the crankshaft has a flywheel with a gear-type rim.

The thrust half-rings are made of aluminum alloy, which helps protect the crankshaft from moving along its axis. These elements are installed on both sides of the main bearing and are fixed using special protrusions.

Specifications

D-240 engines and their modifications

Is it possible to install a piston group from a d-245 on a d-240? after all, the sleeve on the d-245 is shorter than on the d-240

yes, only the piston must have 3 rings

and who else prefers which rings the manufacturer had in mind

the power will not change, the manufacturer is Czech Republic - of course, it’s really expensive

Is it possible to install a turbine on the D-240 without oil nozzles? Adjusting the fuel injection pump is understandable

we dismantled the D 245 of the first sample of large differences, we didn’t find the oil nozzles, maybe there was also a reinforced piston shaft from Yumz, there was a TKR 6 turbine

In principle, on the D-240 you can install a piston from the D-245 and a turbine or what? I have an MTZ-82 and you can squeeze additional power from the tractor. This whole idea is that you are going to overhaul the engine or is this idea not worth the candle

crankshaft from D 245togo and TKR 6 with the original piston guys, we stuck a D 240 on the Zila 157 and installed a turbine for 6 years, the flight is normal, I want to install it myself, but the TKR 6 won’t add much power 20 percent, and if you have a more powerful turbine, then it’s better to find a D 245

What is the difference between crankshafts? I just never had to disassemble the D-245

in sizes 243 (MTZ-80 80 hp) and 245 (Bull 112 hp) there are no differences (only in cast iron - 245 is stronger) visually can only be distinguished by the presence of red paint on the crankshaft cheek, 245.30 (Bison 156 hp) the diameter is increased flywheel mounting castings (there are more holes there). 245.9 (PAZ 136ls, GAZ 122ls) smooth front end of the crankshaft. We are talking about “simple” shafts. On Euro3 there is an additional keyway for the crankshaft speed sensor wheel.

thank you everything is clear.

And for what purpose are the cartridges on the D-245 made short?

They are also short on the D243 and longer on the D65, the piston ones are interchangeable

here is a forum for farmers in Poland, they put turbines on everything, even on MTZ 50 https://dmerkys.ahost.lt/samadielkos.lt/photogallery.php?album_id=4&ro Files: am.jpeg

Guys, no one knows if there is a difference between the D-240 and D-245 heads?

You don't need to change the piston group, but the crankshaft at 245.12 (Bychkovsky) - the tractor one will burst over time. The 245th head differs from the 240th in the presence of seats under the valves and the stiffness of the springs (they are a little stiffer - less “inertia” at high speeds), nothing more. If the casting is MTZ (brick red), then the markings on both begin with 240-. if the casting is GAZ (black) - then 245-.

thank you, but how do I get the crankshaft if the crankshaft of the bull is attached to 5 beds, and on the D-240 it is attached to only 3??

yah. )))))) do not confuse it with the camshaft - yes, on the 240 there are 3 supports, on the 245 there are 5 supports, the crankshaft is one to one, you can’t tell the difference visually, the only thing is that the 245s are marked at the factory (they smear the outer cheek with a brush) red paint - look for this one

Guys, tell me another topic, what pistons generally exist on the D-245 engine and what is their difference?

Guys, tell me another topic, what pistons generally exist on the D-245 engine and what is their difference?

In the combustion chambers, Euro-0.1, Euro-2, and Euro-3, and the piston pin diameter is 38mm, and 42mm, and 3 piston rings.

By the way, on a “factory engine” there is no need to modify anything except the fuel supply thrust, everything else is already prepared

exactly this one, it also comes with a muffler, an air vent, a box (in the picture below in the background it’s thin and flat), and metal tubes

exactly this one, it also comes with a muffler, air vent, box, and metal pipes

no, nothing else is needed, well, some small things in the form of clamps, rings, wiring (to the starter) and a battery. Of course, if you change the engine, you will want to repair and change something else... well, that’s optional

I found an advertisement in the newspaper saying they were selling the D-242 engine. What will I need to “buy” and “finish” in order to put it on the tractor (UMZ-6)?

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