How to Change Valve Cover Gaskets

As long as you let the vehicle sit without running for a hour or s,o all the oil should be at the bottom of the engine or in the pan. However, it's never a bad idea to change the oil after you do this just in case any debris fell into the engine while the work was being done.

If you only changed a rubber gasket, then you don't need to wait at all. Just don't fly off. If you're using liquid gaskets alone or with rubber gaskets, it should say on the tube. Usually it can takes up to 15 hours for a liquid gasket to turn into rubber (so you can try running the engine after this time), but it may take up to 3 or 4 days to achieve a full seal. It also depends on the ambient temperature and how thick you make the paste (it'll take less time when it's hot outside, and thicker paste will take longer to fully cure).

I suggest you hire a mechanic, but you could also go to Autozone to ask for help or use a manual.