engine cold, engine off, expansion tank 95% full. I was only able to pump system up to 12psi..It held steady fairly well..maybe 1/2psi drop over 5 minutes.

engine on, operating temp. gauge went up to 17psi...held steady. still slight leak from back of passenger side head.

engine off, held 17psi for a few minutes. ended test.

my guess is I have a small valley pan gasket leak. I am considering using some stop leak, I know that product is frowned upon on here but since I just turned over 90K miles I expect head gaskets to leak one day..It would be easier to replace all gaskets (valley pan, head) at that time.

suggestions?

 

Justice Brothers works great. I would take the advice of the subject matter experts on here. I decided to go ahead and do a complete gasket, hoses and belt replacement down to the heads.

 

If you are going to go the route of stop leak, get the BG brand coolant leak stop. It remains suspended in the coolant until it comes in contact with air (from the leak). It will not clog your radiator, heater core, coolant passages, etc like the parts store brand of stop leak.

*edit: The leak stop is one of the three bottles used on a BG coolant flush: Cleaner, Sealer, and Super Cool additive. BG wouldn't put their reputation on the line by adding their leak-stop sealer to every flush with their products, if it could cause a problem with the cooling system.

 

I don't think I've seen BG before. Do any stores carry it or is it online orders only?

 

http://www.bgprod.com/home.html

It isn't sold in retail stores, only repair shops have it, but I have seen their products for sale on Ebay and the like from individuals.

 

I found coolant is leaking out from the manifold outlet pipe, how do I fix this? Is there a o-ring inside manifold outlet pipe? Or gasket I need to replace? Thanks!