1. The main reason for the sliding teeth
The advantage of the aluminum oil pan is that it is light, so most of the engine oil pans are made of aluminum at present, but the bolts are only made of iron. After the two are matched, the requirements for tightening force are very high. We all know that the thread strength of iron bolts is stronger, and a little carelessness may cause the threads of the oil drain screw to slip. Therefore, the tightening force is the key to determine the quality of the oil drain screw.
2. There are several common problems that cause bolts to slip:
1. If the tightening force is too large, the thread of the screw hole will be deformed, resulting in slippage.
2. When the bolt is screwed in, it is skewed, causing mechanical damage to the aluminum thread.
3. Use a pneumatic wrench, too fast disassembly will damage the thread.
3. What should I do if I encounter slippery teeth?
When many people encounter this situation, most of them will replace the oil pan according to the instructions of the 4S shop or repair shop, and the maintenance cost is very high. In fact, if we repair the thread, it can also reach the factory's craft level.
Step 1: Ream the hole with an electric drill
The original thread is no longer usable, so we use an electric drill to enlarge the original screw hole. The main reason is to make it easier to screw the oversized tap into the screw hole.
Step 2: Choose the tap that is the size of your original car bolt No. 1
It is difficult to recover after being covered with water, and the damaged thread cannot grow again, so enlarging the bolt hole is the only way. In the selection of taps, we need one model larger than your original car bolts. This is very critical. Too big and you won't be able to fix it easily, too small and it won't help
Step 3: Follow the principle of half a turn and one turn back
a. Before screwing in, apply sufficient engine oil to the tap for lubrication.
b. Rotate to advance half a circle each time. Then rotate back in a circle.
c. Rotate one turn left and right, the main purpose is to make the new thread groove that has been opened more smooth. This is not easy to make the tap head high temperature.
Notice:
When choosing a tap, we must choose the same model as the new bolt thread. If the thread model is different, you will spend a long time, but the bolt still cannot be screwed in.
Step 4: Completely Clean Threaded Holes
The tap must be completely screwed in, and there is no resistance to screwing in and out before it can be completed. Due to the generation of a large amount of iron filings, the threaded holes were cleaned with a cleaning agent.
