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MAZ repair: principles and basics

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MAZ repair: principles and basics
MAZ repair: principles and basics

MAZ vehicles are equipped with engines manufactured by Avtodizel OJSC. The plant began its work in 1916 and is the oldest manufacturer of diesel engines in Russia. The most popular and common are YaMZ-236 and YaMZ-238. Repair of MAZ with the above engines will not cause you any trouble with proper preparation and skill.

Types of recovery

Repair of MAZ vehicles should be divided into current and capital. With the current repair and restoration procedures, operations are performed to restore the he alth of certain mechanisms using locksmith work. In this case, the disassembly of the power unit is carried out only to the extent that is necessary for access to faulty parts and mechanisms. Timely repair of the MAZ engine will allow to delay the need for a major restoration and increase the mileage during the period of interservice work. This allows you to increase the resource of using the power unit. Performing maintenance should help replaced or repaired parts survive at least TO2.

MAZ engine repair

It should be mentioned that when performing the current restoredamage is repaired by replacement. You can also apply repairs to parts that are not basic. Based on the above, we can say that with the current performance of operations it is possible to replace piston rings and pins, liners and gaskets, as well as grinding seats and lapping valves.

Overhaul of MAZ - a procedure performed to restore the performance of the motor. It is designed to provide at least 80% of the resource of the new engine. When overhauling a car, it is necessary to completely disassemble, wash, clean and / or replace defective parts, further assemble and test the power unit.

Overhaul Methods

The overhaul of MAZ is carried out by the following methods:

  • Anonymous - when performing operations, it is not necessary to preserve the ownership of the restored or replaced nodes to a specific instance.
  • Unidentified - is individual, so it is necessary to keep the ownership of the repaired parts. It is a very high-quality method, as it allows you to leave the most complete resource of nodes.
  • Aggregate - a subspecies of the impersonal method. The bottom line is to replace defective parts with new ones.
  • In-line - repairs are carried out at specially equipped places for this with an established sequence.
MAZ repair on the road

Repair and replacement of bushings

Loose bushing indicates a high degree of wear on the inner surface of the camshaft. To restore the gap in the bushingsbearing necks are regrinded, the size of the latter must be reduced by no more than 0.75 mm. The bushings are replaced by pressing them into a previously cleaned hole in the cylinder head. Do not forget that the sending sleeve is installed before this, it is designed to provide a certain protrusion of the end of the sleeve.

Camshaft replacement

The camshaft is being replaced due to critical errors in the operation of the pusher axis. To completely replace the camshaft, you must completely remove the motor, radiator and front of the engine. Do-it-yourself MAZ repair is a difficult undertaking, but this operation is almost impossible to do alone, so it is recommended to contact specialized organizations.

MAZ gearbox device

Transmission Troubleshooting Operations

Restoration of the checkpoint is one of the operations that is included in the overhaul of MAZ and is carried out exclusively on special equipment. To do this, it is necessary to completely disassemble the gearbox, identify defective components and parts and carry out their diagnostics (with further repair and restoration operations) and / or replacement. But it is worth remembering that only the crankcase and cover are subject to restoration, all other parts are replaced with new ones.

Crankcase repair

Restoration of the crankcase is performed in case of wear of the bearing holes and pins and if the thread is damaged. During the repair, bushings are installed. To do this, the hole is bored to a diameter of 15.5 cm, and the undercut is 3 mm larger indiameter.

In this case, the following conditions must be observed:

  • depth - 2.5mm;
  • bushings are pressed into finished sockets;
  • tension no more than 0.15mm;
  • holes are bored linearly.
MAZ gearbox repair

Thread restoration occurs in this order:

  1. Drilling with a diameter of 17.1 mm is performed and threading is performed.
  2. Screwing the screws with glue.
  3. Deployment.

Repair bearing cap

Performed in case of cracks, damage to the ends and wear of the holes. If breaks are found on the pipe, the deformed section is cut off. A hole is bored to a diameter of 5.5 cm to repair the bushing. Next, a chamfer of 5 x 45 ° is ground off and the sleeve is pressed. After that, the part is welded, and the holes are turned. The final processing is carried out on a circular grinding machine. When performing this operation, the following conditions are met:

  • holes that are damaged are welded with an electrode, and various deposits are cleaned;
  • drill holes with a diameter of 11 mm and countersink from the side of the pipe.
MAZ under repair

Also, when repairing the lid, the following requirements are met:

  • holes for oil seal no larger than 0.88 mm;
  • allowed misalignment of flanges and undercuts no more than 0.05 mm;
  • grooved holes no more than 0.02mm.

When the oil seal bore is worn, a bushing is used. The procedure is as follows:

  1. Boring with a diameter of 68 mm and a length of 24.5 mm.
  2. Boring the sleeve.
  3. Aligns with the groove on the cover.
  4. Cutting the ends of the sleeve.
  5. Chamfer and hole boring.


Repairing MAZ may seem like an overwhelming task, since the car is a truck. Yes, you need help and special equipment to perform some operations, but you can do in-line fine restoration yourself.

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