I'm replacing the valve cover gaskets on our 1993 Legacy 2.2 Liter Normally Aspirated engine because of a small oil leak at the front base driver side valve cover. I took it off and it seems that someone put a silicone type sealer along with the gasket on it when it was maybe replaced before.

 

What product/chemical can I use to remove the old silicone-type stuff? I am afraid that if I scrape it that I would end up damaging the cover and creating another leak. I have already used carb/choke cleaner and it seems to do nothing to the silicone. Also the silicone is a red color if that tells you anything.

 

Thanks in advance!

Hi,

 

Speaking from the point of view of a '96 Legacy with the 2.5 DOHC: the silicone sealant is required. It must be applied at the corners of the gasket, that is, at the sharp angles formed when, for example, it arcs up to clear the cam housing. It is also required at the location of the rubber plugs towards the rear of the head.

 

Removing the old silicone is easy, I used a plastic scraper and it came right off. Be careful with anything metal as that aluminum is very easy to gouge. Once removed, clean the seating surfaces thoroughly, and I mean, thoroughly. If you don't, the new silicone will not adhere and you'll get leaks in short order. I used a rag with some lacquer thinner. Clean the gasket too because it may have residual plasticizer from the molding process.

 

Make sure you use a "sensor safe" silicone sealant, available in most auto parts stores. Apply it to the head and then get the gasket into place carefully, making sure that the silicone doesn't smear. Don't use too much, either. No silicone is required on the valve cover side of the gasket.

 

It all sounds a bit intimidating and fussy, but it really is quite simple to do. Good luck with it.

 

Regards,

Adnan

Thanks. I didn't even think of using a plastic scraper. That's a great idea. I was afraid of using my metal scaper because it may gouge the metal and lead to an improper seal and another oil leak.