Coolant / Oil leak

[David Sutton]

Just before I packed up my car to be shipped back east, I noticed on the undercarriage there was coolant, and oil dripping down, forming a burn stain on the bottom of my turbo housing. I took it to a local shop, and they said it's probably leaking oil and coolant from the turbo, and I should get them to buy me and install a new turbo.. yea right. He said that my power should be shit and I shouldn't be spooling properly. Well my power isn't shit, and the spool is a loud hiss, so I assume it's not leaking from the turbo itself. I found that my vavle cover gasket is leaking from the lower left bolt, that accounts for the oil i'm seeing. I followed the trail, and sure enough it ended up down by the turbo housing. But as far as the coolant goes I'm at a loss. From what I've looked at , I've seen no leaking coolant. My resovoir was fairly low, which makes me think there IS a leak somewhere. Our turbos are only oil cooled, not water cooled, correct? I know that the GT4, and WRX are water cooled (from what I've read) but I didn't think ours were, discounting any leaking of coolant from the turbo housing. I also saw no visible cracks on the housing, and have turbo timed this thing since day 1. The turbo is a s16g and only has MAYBE 30 k on it. Maybe. Anyways, I'm just curious as to where coolant could be coming from in that area, and what to do. :| Thanks guys.



EDIT** NM it is water cooled, thanks to mr. Toor for the info.
Cheers,

   Dave

[Mike Schmid]

Did you check the lines to and from the turbo?  That or maybe the thin metal pipe that sits behind the exhaust manifold and runs from the waterpump to the transmission side of the engine.  It's a fairly thin pipe and might have developed a small pinhole or crack.  Also the upper rad hose and thermostat housing to overflow tank hose are nearish to the turbo and coul dpossibly shoot coolant onto it.  I had a pinhole leak in a hose once that was shooting a stream of coolant ~1' onto the other side of my engine bay.  

If it doesn't leak at idle try revving it up and watching under the hood.  The increased coolant pressure at ~3000 rpm will sometimes open up a leak that is otherwise sealed at idle.

[Martin Raska]

I had an oil leak through a head manifold stud it appeared.  Presumably they go into an oil gallery, or at least one does.  It ceased with new studs, but was broken inside the head.