Valve Cover Gaskets
by Pat Goss
One of the most common places for an oil leak on an engine is and always has been the valve cover up on the top of the engine. Back in the day the valve covers used to be made out of tin and they were kinda fragile. These tin valve covers used flat gaskets made out of cork or sometimes rubber. Well, that evolved into aluminum valve covers which were machine flat on the bottom, still used a flat gasket, and in most cases that was rubber.
Well nowadays what they're doing is they're using these o-ring type gaskets, and these are designed so there's a notch. It is cast into the valve cover. The o-ring gasket fits down into that notch and it makes a better seal. Now on either one of these you got to make sure that you tighten them properly. Best ways to do it with an inch pound torque wrench. You could use a foot pound wrench such as we have here, but the big thing is make sure that they're torqued to specification and they're torqued in the proper sequence. That is a big factor in these things. So make sure you read and follow label directions.
Right, now another thing is that we have gasket makers gasket sealers and so on. All of these things have a purpose, but only use them where the manufacturers says to use them. And only use them in the way the manufacturer says to use them. Just don't blanketly put some of his stuff on any and every gasket you come in contact with, because it could actually cause leaks.
Now speaking of tightening things, one of our clients was on the road had a leak. Stopped by a shop and the shop put a new valve cover gasket on it. Now the guy told me he watched the technician use an air impact wrench such as we have here to tighten the bolts after he got the valve cover back on. He should never do that and here's why. It broke a very expensive valve cover, and he still had a leak.
So these are the things that we have to look out for. Always make sure that you tighten valve covers properly, sequence and amount of torque. Always use the proper type of gasket. Never use gasket sealers except where they are recommended, and always use them in the recommended manner, so these are the things that can make a valve cover job successful. And if you have a question or a comment drop me a line right here at MotorWeek.