I have a small seepage of coolant from between the block and head gasket right behind the thermostat housing It is right below the head bolt in that same area. Can get a pic if needed.

It is slow enough that I don't really notice the coolant level going down and I don't have any bubbles in the radiator.

Is this comon at all? Just let it go that way? Retorque the head? Get ready to pull the head?

As far as I know the head has never been off and it has 206K miles on it now.

 

Are you sure it's not just the hose or the outlet housing gasket leaking? On my 89, the gasket is a big thick piece of ruber that holds the thermostst in the outlet housing.

Somebody else will have to tell you if the head gasket is prone to leaking but I would doubt that's the problem. How many miles do you have on it? Did you get it new so you know it's never been overheated? Alumaseal works well for most small leaks.

Edwin

 

Pretty common place for a h-gasket leak, from what I've read here. If it's leaking slow and there's no coolant in the oil, I'd say run it.

 

It is definately comming from between the head and block about an inch behind the t-stat housing on the passengers side of the block. Right below the head bolt in that area. I first noticed it at the end of an 8hr 70mph pull down to southern OK last month.

I hoped what G1625S said would be the response. Seems to be an external leak only, not to compression.

Will see what others say.

 

If compression from the engine, especially under boost, leaks into a coolant passage, you'll know about it in a hurry...the coolant temps would go up rapidly with all that air in the system.

 

Same thing started happening on mine(190K) last year. Its gotten around to the front. I first retorqued the two front head bolts, no help. I tried Prestone stopleak, waste of money. Bards big pellets slowed it down alot. I bought a new Standt Lever radiator cap/ Removed the lever and spring diaphram, put a bolt with a lockwasher in the lever hole, all to keep the pressure as close to zero as possible. The temp gage reads like it always did up/down, up/down. I've had other old trucks that worked fine with no radiator pressure. I'm using Bards big pellets and checking the coolant (looks like chocolate pudding ) and hope to put off a new head gasket as long as possible. I still have good power and last trip got 21.5 mpg. Just keep checking those fluids ;-P