geekapalooza

Glad to finally be a part of the 928 list! I've been in lurk mode a while and am just now getting around to signing up.

Question:
My 87 S4 A/T has a slight coolant leak, accumulating in the front V portion of the engine. My first thought was water manifold O-rings, but I just spotted a coolant trail coming from apparently further behind the water manifold on the passenger side. The pic attached shows a coolant trail running down in the center of the pic, sorry for the out-of-focus, but you get the picture.

Is it the head gasket? If so, where do I go from here (besides to start praying)?

Thanks,
Rob

Scott M.

Find someone that has coolant pressure tester. Attach to overflow neck and pump to 15 psi. Watch for leakdown. You may be even able to see if there are bubbles coming from your trail area.
I do both hot and cold readings.

OR...

Get some dye (most good autopart stores) and a UV light, follow their procedures.

Scott
93 GTS 6.5L
89 GT
...others

Kevin in Atlanta

O-ring at the bottom of the thermostat housing is a likely suspect.

borland

Autozone has a tool loaner program. One of the tools they have is a radiator cap tester that works great on the 928 for pressurizing the coolant system.

Replacing the thermostat housing is much easier if you have the intake manifold removed.

If you replace the thermostat housing, replace all three o-ring seals and lubricate them gererously with silicone grease.

Lizard928

pull all the items in the area and follow the trail to locate the source, or do the pressurizing test

geekapalooza

Thanks a bunch for the tips, much appreciated. Now if I can just get rid of this dang cold, I'll get out there and work on it!