Replace head gasket
 

How do you know when to replace your head gasket? I wanted to do preventive maintenance but don't want to create any problems by tearing her down. She is an 88 420HP with 500 Hrs. After inspection, I saw a little seepage and I'm seeking your advise.

Re: Replace head gasket
 

The first question I would have to ask is if there is salt water or fresh water in that engine? If it has salt in it, I would be surprised they lasted this long. If fresh, you most likely would not have to change them as a maintenance routine. They would only need replacing if you were to tear down the motor for some other reason. Assuming that this is a Chevy motor, they have great clamping force on their head gaskets. They almost never wear out unless the engine is overheated.

Re: Replace head gasket
 

We ran into a strange situation where the water ports in the head did not line up with one gasket perfectly. We were having a little seepage. Had to replace the head gasket and put a little goo around that particular area. Never did figure out why it was machined slightly different.

It has been faultless since.

Re: Replace head gasket
 

Yes, it is in brackish water. Also, how many hour job is it to replace the head gasket on a chevy 420 hp?
Thanks