CLUB OF CAR FANS
/WORKSHOP
TASK FOR THE CHIPPER
FIND A CLEARANCE IN THE LUBRICATION SYSTEM Pore Fails
TEXT / ANATOLIY WAYSMAN
This story is instructive for beginning car repairmen - once upon a time and for me it became a lesson.
Once they dragged in tow a five-year "eight" with a rattling motor. They started it for five seconds - they listened … The crankshaft has definitely "gone" - the engine obviously needs to be sorted out. But before, he asked the owner: “medical history” is one of the components of a competent diagnosis.
As it turned out, despite a moderate mileage of 90 thousand km, the engine had already visited the “capital”, after which it had passed only 5 thousand km and again “died”. I was wary: “How did the emergency oil pressure lamp behave after this repair was completed?” The answer confirmed the suspicions - it did not go out for a long time after a cold start and even lit up on a warm engine when the speed increased above average. Immediately measured pressure control gauge, screwing it instead of the sensor. Indeed - as the speed rises, the arrow tends to zero.
So, there is no choice - they removed the engine from the car and took it apart. Surprisingly, no defects were found in the lubrication system. The oil receiver is not deformed, the oil pump is assembled as it should - checked. The piston group is live - it is not necessary to change, but it was necessary to reshape the crankshaft journals and select repair liners instead of broken ones. This is a sign that the engine has ended from oil starvation.
We were in no hurry to assemble the engine and, moreover, put it in its place without solving the mystery of the lack of lubrication - it would be foolish to hope that everything would be repaired. Just in case, I sawed off an oil filter removed from the engine - and there were no obstacles to the passage of oil. But intuition suggested: the reason is somewhere up to the pump - as if they didn’t let him drink enough oil - they save …
And then the fun began. The client accidentally made a mistake (why did you keep silent before? !!) that the emergency light began to be an eyesore … a couple of years ago, that is, long before the first repair! At first, it caught fire only at maximum engine speeds, then at lower ones, and recently, the owner generally avoided accelerating in fifth gear above 100 km / h so that the pressure did not drop. I tried to pour oil per liter more than normal - to no avail. Then he decided to give the engine to the bulkhead - alas, it did not help.
And now our entire service is on the ears - what haven't we checked yet? For some reason, even the channels of the cylinder block were washed, purged, and at the same time they were pressed - there are no workarounds for oil, only to the crankshaft and cylinder head. Once again I turn the carefully washed oil receiver in my hands and look through the hole at the grid - everything is clean. Guess - like lightning … I turn on the electric rail, grind the tin rolling and separate the oil receiver into two halves. So it is - clean holes are concentrated only in the center of the grid, and everything around is overgrown with a black mass resembling hardened bitumen - you will not even dissolve this with gasoline. Now the behavior of the bulb is clear. Oil thickened in the cold did not have time to flow into the oil receptacle, and the pump drove it into the main line with pharmacy doses - where does normal pressure come from? The same thing is hot at high speeds - the pump capacity is large, and there is not enough oil at the inlet. On such a dry soldering, the liners do not last long, which was confirmed.
Such a way to unravel is easy to explain - the “eight” oil receiver, unlike those used on most other engines, is covered with a lid - so as not to trap air when the oil is poured to the side in turns. Through a hole the size of a coin, you will see only the center of the grid, and what is there along the edges - alas, the design is not folding. In the corners inaccessible for cleaning, all rubbish accumulates - either from the abuse of cheap fake oil, or from the untimely replacement of the normal one.
