If you have not adjusted the valve clearance for a long period of time, the adjustment bolts and/or lock nuts can be very tight and difficult to unlock. Sometimes, cutting and/or damaging the thread is the only solution. In this case, you will need to install new sets of screws and/or lock nuts.
It is also possible that the set screws may be worn at an angle or hammered due to the age of the engine. In this case, the valve clearance can no longer be adjusted correctly, replacing the nuts and adjustment bolts is the only solution.
Different types were used for the different engines. If in doubt, measure the old adjusting screw before ordering. The latter is necessary in CT/CZ engines, two sizes are used in these engines.
Attention! Our adjusting screws and locking nuts are of very high quality, many adjusting screws on the after-market are of very poor quality and will be broken after a few kilometers. It is an important part to keep the valves intact, so don't use cheap alternatives, it can cost you a lot of money.
Note : M8 x 1.0 locknuts have a dual function: they were also used as locknuts for the stabilizer bar bolts on Beetle, Karmann Ghia, VW Thing and Type 3 models fitted with swing axles.
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