928 coolant leaking, help!!!

[SharkTech]

Very weird, started the car up today and at idle, under the hood, I noticed that coolant was spitting up in the air from the front belts. There is a trickle coming out by the power steering pump dumping onto the power steering belt and getting flung. As I turned the car off then looked underneath and noticed a small stream of coolant leaking right by the power steering pump, then it slowly stopped leaving some coolant in the car. What by the PS pump could be leaking coolant???

Hmmmmmm....

Where to start?

FYI
1979 Porsche 928, manual, red/black

Thanks Pelican!!!
BTW,
86 na 944 sold.

[Dean_Fuller]

Sounds like the water pump. Its "inside" the front covers and if it leaks can appear to come from PS pump area. Whens the last time the WP was changed? Don't worry...its not bad but it may be time for a new one plus while your in there a new timing belt and tensioner rebuild.

[SharkTech]

Belts were done 2500k ago, WP was not. How difficult to do WP? Do think it is, FOR SURE, water pump or could it be a hose or connection to investigate, etc?

[Danglerb]

Get all the easy stuff out of the way, intake tubes, both timing belt cam covers, etc. and take a good flashlight and an inspection mirror and look around as you clean up all you can.

Start the car and watch for the first sign of a leak, then repeat the clean and inspect until you find the source or eliminate everything that is easy to fix.

Replacing the WP is slightly less of a job than a TB, but since your in there you should CAREFULLY inspect the TB work.

[Dean_Fuller]

Originally Posted by Danglerb

Get all the easy stuff out of the way, intake tubes, both timing belt cam covers, etc. and take a good flashlight and an inspection mirror and look around as you clean up all you can.

Start the car and watch for the first sign of a leak, then repeat the clean and inspect until you find the source or eliminate everything that is easy to fix.

Replacing the WP is slightly less of a job than a TB, but since your in there you should CAREFULLY inspect the TB work.

Totally agree. Easy enough to check before major dismantling takes place.

Wouldn't be the first time a WP went because a new TB and rebuilt tensioner was mounted. A new TB puts a lot of stress on an old WP. Remember the WP is held in place with 14 bolts but at very little torque....like 7 or 8 ft lbs. Would not take much to get it to leaking.

[MPDano]

Exactly why I always say replace the WP when you do the TB. I do it in any (not just 928) of my cars. They are never that much, but are a pain to do after the fact.

[DanielDudley]

Do the seals, rebuild the tensioner, replace the water pump. Inspect the timing belt carefully.


Guys, is it time for a FAQ sticky at the top of the page ?

[Danglerb]

One of the reasons I don't like to jump in timing belt first is that a car thats been parked a time needs driving and heat cycles before all of what needs to be replaced will be obvious. I think that may be the case with a WP, seepage while its sitting damages parts of the sealing system, but takes a few thousand mileage for total failure.

OTOH this sounds like a "lot" of coolant, so maybe its something simple like a hose splitting.

[SharkTech]

Thanks alot guys for all of the feedback. Most of my experience is with the 944's, new to 928 guts. Now I will agree this is an all at once situation, and went from nothing leaking underneath to again a stream of coolant after car pressurizes to idle, etc. Should I inspect lines and what not first, before cover dismantle? Does the full front covers need to come off before WP inspection is possible? Does anyone know of a good diagram of the front of this car, outside the workshop manuals? They are really not giving me the diagram i am looking for to learn all the front end architecture. I also have to install a new viscous fan belt, for now, until electric fan conversion can be done, which I want to do soon. I see the PS belt needs to come off before the viscous belt can be installed, right? The viscous belt seems to need to go from pass side small pulley and over both center pulleys, correct? Basically I am asking if the viscous belt needs to wrap around 2 center pulleys, seems to be. Again a full front diagram will be of much help to understand where coolant runs, how WP interfaces, TB's, etc.

Thanks again guys.

[SharkTech]

Well, found the problem, actually very minimal compared to what it could have been. After getting the belly pan off and the cam cover, etc, and inspected the WP, Timing belts, tensioners, etc, looks good, actually very good. Looks new, to say the least, no leaks, sweating, timing belts look new, nothing worn. I did find the coolant leak problem, actually a pin hole in the curve of the lower radiator hose, which was spitting a fine not noticeable stream of coolant, once pressurized, right against the outside of the power steering pump seeming to come from that area since it dripped down. Anyway, replaced the lower and upper rad hoses, did all of the belts up front(power st, clutch fan/air pump, alt, etc) and all is well. Took the car out for a nice long drive, sitting here and there letting it run, no fluctuation in temp, etc. happy happy happy. Thx guys for your feedback here, know much more about the front end/cooling system now for the 928. Rock on...

[Danglerb]

A 928 is like Pizza, when it good its very good, and when its bad, its still pretty good.

Congrats on a successful repair.