Table 3.4. Engine break-in cycle
Frequency of rotation of a cranked shaft, min-1 | Break-in time at a given speed, min |
750-800 | 1 |
1000 | 3 |
1500 | 4 |
2000 | 5 |
Having installed the engine on the stand and started it, check:
- no leakage of coolant or fuel between mating parts and in pipeline connections;
- oil pressure and no oil leakage through the gaskets;
- idle speed;
- tightness of the connections of the elements of the power supply system (air and fuel supply systems).
If extraneous knocks or malfunctions are found, stop the engine, eliminate them, and then continue testing.
If oil leaks through the gasket between the oil pan and the cylinder block, tighten the mounting bolts to the recommended torque. If the leak continues, check the gasket and replace if necessary.
If oil leaks through the gasket between the cover and the cylinder head, check the gasket and rubber bushings on the studs of the cylinder head cover. If necessary, replace the gasket and bushings, following the recommendations given in subsection «Engine assembly».
After repairing the engine, it is necessary to observe a certain mode of operation during the period of running-in of the working surfaces of new parts. This applies in particular to those engines on which pistons, connecting rod and main bearing shells have been replaced, crankshaft journals have been reground, and cylinders have been honed or cylinder liners have been replaced.
Therefore, during the break-in of a repaired engine on a car, do not subject it to maximum loads. The engine break-in should be carried out at the speeds and loads recommended for the break-in period of the vehicle.