Engine cylinder gasket is a component that is easy to be damaged. However, many repairmen did not pay attention to the tightening torque of the cylinder head bolts after replacing the cylinder gasket, which caused secondary damage to the cylinder gasket in a very short time and caused economic losses to kayou. No, “Chengdu fat man” came here.
After the vehicle came to the store, the fault was that the water temperature of the vehicle was not high, but the expansion water tank sprayed water outward, and there was oil-water mixing. Pull out the oil dipstick for inspection, and the oil was also mixed with cooling water. At first, it was suspected that the oil radiator was damaged, but generally, the damage of the oil radiator will only produce oil-water mixture in the coolant.
Because the oil pressure is higher than the pressure of the cooling system, water generally does not enter the oil, so the fault point should appear on the cylinder pad. After asking the owner, he learned that the cylinder pad of the car had been replaced two months ago because the cylinder pad was damaged. So far, it is basically determined that the cylinder pad has a problem again.
Remove the valve cover, which is full of emulsified oil. Remove the cylinder head and inspect the cylinder gasket. It is found that there are obvious damage marks at the oil channel of cylinder 4. The fault point is here. Clean and check the plane of cylinder block and cylinder head, and no obvious unevenness is found.
It is analyzed that the tightening torque of the cylinder head bolt is insufficient, resulting in the flushing of the fault point after being used for a period of time, resulting in the fault of oil-water interlocking. Check that the cylinder gasket is a genuine product. There are no factors causing failure by using fake goods. Replace the cylinder gasket, tighten the cylinder head bolts with a preset torque wrench as required, and then test run, and everything returns to normal.
This is obviously a secondary fault caused by inadequate maintenance by the repairman. When tightening the cylinder head bolts, they did not follow the specified torque, or there was no special torque wrench, and they tightened the cylinder head bolts completely by hand. This way of tightening the bolts will cause inconsistent tightening torque of the cylinder head bolts, resulting in a secondary failure that the cylinder gasket will be damaged again soon after replacement.
The tighter the bolts, the better. In particular, the bolts on the engine need to be tightened in strict accordance with the specified torque, otherwise it is easy to have secondary faults, which will affect the normal operation of card friends and cause certain economic losses. Here we also call on repair shops and repair shops to spend this money to buy a preset torque wrench. Today, with the gradual improvement of manufacturing level, extensive maintenance can no longer adapt to the current market. Only continuous learning and progress can meet the needs of the market.
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