gf261

Got ready to change the fuel filter on my 89' and couldn't find my large metric open end wrenches. Anyway, hopped in my 87' to run to the hardware store and realized that I didn't have my wallet. Got back out with the car running and smelled COOLANT!!!!! Popped the hood and found coolant in the sort of hollow spaces behind and underneath the upper coolant hose. Water pump failure? The PO, curse his soul, changed the timing belt but NOT the water pump. All of my previous vehicles (non-Porsche) have leaked coolant to the bottom of the motor. Is this common for the 928 to leak here on the top of the water pump? Thanks in advance.

Ketchmi

It's probably the large O-ring on the bottom of the thermostat housing, common problem. Normally when the waterpump goes it's accompanied by coolant coming out from underneath the pully area, not above. Your problem could also be the small heater hose that runs to the passenger side fenderwell hardline. Something to take care of but not panic about.

Dave
Motorsport

gf261

Is the small hose that you are talking about the one that runs to the heater valve?

Ketchmi

It runs into the heater core. It attaches to the thermostat housing beneath the upper radiator hose. The other side of the heater core is what connects to the heater valve.

Dave
Motorsport

gf261

I don't think that one is leaking, but will take a look. I can't see any sign on the front of the thermostat housing that it is leaking, maybe the back portion? I don't have any strange noises or coolant beneath the vehicle so hopefully it is just that O-ring.

Ketchmi

The thermostat housing has a large section that goes directly down into the block. It's behind the area that you are looking, you will probably need a flashlight. I have seen several fail but it's usually just weeping and causing the pools of anti-freeze you are describing.

Dave
Motorsport

gf261

Dave, thanks to your insight and my second Glenfiddich neat, my nerves are calming. I do appreciate the help. Just another testament to the powers of Rennlister's minds and single malt Scotch. Thanks again!

Ketchmi

Where's mine?

Dave
Motorsport

Garth S

If it was Glenmorangie you were pouring, I might consider adding a comment too ...
If you can swing a quick pressure test on the system, there should be no mystery: in addition to the points Dave mentioned, the heater valve and its inlet hose are still suspects even though they are at the back of the Vee. Hope it's only a hose ....

gf261

I enjoy Glenmorangie myself from time to time. Local store doesn't stock it regularly so sometimes you have to settle. Scotch for everyone if everyone was here! On the heater valve subject, I just replaced it a couple of weeks ago. I am going to replace the hose from it to the front of the block as well while I have the thermo housing off. My next adventure is figuring out a vacuum line problem. I have no vacuum to the heater valve, so still have hot air coming through the vents.

borland

In addition to the pump shaft seal leaking, leaks can develop at the pump gasket. So you might still have a pump leak in the area your concerned with.

The fuel lines require two flare wrenches for each joint. Otherwise your probably going to deform the nuts and make it difficult to remove the first or second time around. Better find that wallet and buy some good flare wrenches.

Ketchmi

As far as the vacuum to the heater valve, check the one way valve (blue & black if stock) for proper operation. It's located off of the brake booster and supplies vacuum to the resivor (sp?). If this is bad, your flappy may not be functional either.

Back to my Almendrado (Almond flavored Tequila! Mmm Mmm Good!)

Dave
Motorsport

bigs

Hey! Get back to working on my car!

(reservoir)