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I havent written on this account on this forum before, I used to write a lot a few years ago but I dont even think that account is still around. Either way I might aswell give you guys a bit of a background story here before we get to the actual problem. I am a professional Mercedes mechanic and Ive been a tech for around 15 years but Ive been around cars for the past 25. I bought my first 944 Turbo in 2009 and since then Ive had 5 944s, two turbos, one S2 and 2 N/A 163 hp so I know them inside out, Ive done pretty much everything thats possible to do on these cars, Ive raced them, Ive dailied them and Ive replaced or repaired every nut and bolt in these cars.
3 years ago however I bought the car that killed all my interest in Porsche and planted the seed to an evergrowing hatred for the brand and these cars. A 1988 Turbo (not an S). Its in beautiful condition, very low miles with a full servicehistory, all original except for the wheels.
I managed to buy it from a friend for fairly cheap because it had a boost issue that he couldnt fix. He spent so many hours and so much money on this one issue that he got so fed up with it that he sold it to me for a good price. Great I thought, I took it home and went throu it. Found a leak in the wastegate which caused it to overboost and cut ignitiontiming. Changed it to a stock wastegate and it ran fine, albeit a bit slower but it ran as it should (or atleast somewhat).
Then the car started leaking coolant. The culprit was the big radiatorhose going from the waterpump to the radiator, powersteeringfluid had leaked on it which had caused it to go spungy and eventually it burst. I changed the hose but the leak continued, albeit not as much. The leak was coming from the waterpump hose that goes to the steelline above the manifold. The problem (I thought) was that the fittings for the hoses were so badly corroded that the hoses werent sealing properly so because the car was due for a timingbelt anyway I decided to change the pump for a good condition one I had on the shelf.
Ofcourse when I proceeded to do that one of the bolts broke for the waterpump which I then had to drill out. Because we were in the process of actualy building my garage/workshop the car was left sitting for almost 2 years without the waterpump.
A few weeks ago I finally decided to put it back together. I drilled the broken bolt out and fitted the spare waterpump I had with a new gasket and new hoses and new hoseclamps, new timingbelt, new balancebelt and new pulleys and tensioner.
So after a few hours it was finally time to start it. When it finally started it died after 2 seconds again and then it wouldnt start, at all. Completely dead. It took me an ENTIRE day, and I mean from early in the morning to 10 pm before I finally managed to figure out what the issue was. Yes the Alarm controlunit had decided that it no longer wanted to cooperate and so it cut the DME relay. After having bridged the Alarm the car finally started.
Finally after 2 years the car was running again, althou it was whining like crazy from the balancebelt so I had to readjust that again but that was no big deal. Took it for a testdrive and parked it in the garage. A few days later I go back out to the garage and see a big puddle of coolant on the ground and the words I uttered are not suited to most peoples ears.
Wanna guess where it was leaking from? Yes exactly the same spot it was leaking from originally, the upper waterpump hose that goes to the steel line above the manifold, where it goes into the waterpump. So my thought was after having looked at it that the hoseclamp was on a bit sideways, thus riding on the flange of the connection with half the clamp. So I readjusted the clamp so I KNOW its on correctly, retightened all the clamps HARD this time. Went for a drive, no leaks. But this time I was less enthusiastic because I know it usually dont leak when its hot. So I parked it in the garage and left it for 2 days, from Sunday to today.
Today I went back out into the garage and sure enough theres a small pool of coolant on the floor again, maybe the size of a few coins. And ofcourse, from exactly the same place again. How is this possible? Theres a "new" waterpump on, atleast it didnt leak from the car I took it off from and its not corroded at all. It has a new hose and new hoseclamps and I cant tighten the clamps harder ot theyre gonna either skip a tooth or cut the hose. Im completely at loss for words, its as if this car is cursed and I really do understand now why it has such a low mileage on it. Ive had it for 3 years and I think Ive driven 500 miles in total with it.
So my first question is ofcourse if anyone has even the slightest idea of why this wont stay sealed and what to do about it, because at this point I have no idea.
My second question is. I hate this car, I hate it so much Im close to setting it on fire. Obviously I will get rid of it, as soon as possible, however. It has not passed inspection for 3 years, because it doesnt have a Cat, the previous owner took it off because they suspected it was plugged. It also doesnt have reverselights because it keeps blowing the fuse. Theres a few other minor issues that needs fixing before I can get top money for it. But at the same time Im very reluctant to spend money on it and I do not have the motivation or time for that matter to fix it.
Is it worth selling as it is, potentially maybe even with a loss? Just to get rid of it? Or do I suck it up and fix all the issues and try to get it inspected (which would probably drasticly increase its value)?
PS. I live in Sweden....[edited]
Last edited by Tom M'Guinn; 10-27-2020 at 01:39 PM.
Reason: conforming to Rennlist rules
Re the leak, there's nothing particularly special about the pipe/hose where you are getting that leak. First thing I'd do is pressure test the cooling system to see exactly where the coolant is coming out. The leak may be somewhere else and just dripping there. If it is coming from the joint you suspect -- where the water pump hose connects to the steel heater pipe -- I'd remove the hose and really inspect the end of the pipe and its bead for corrosion, out-of-round, dents, etc. If the pipe is round and smooth, with a smooth/round bead all the way around, and if the hose is new and healthy, that connection should seal up no problem.
this seems to be a very common 951 ownership perspective. i know i have hated mine many, many times. even when you hate them, they're still a great looking car. when it's running properly, you just can't get yourself to sell it.
Re the leak, there's nothing particularly special about the pipe/hose where you are getting that leak. First thing I'd do is pressure test the cooling system to see exactly where the coolant is coming out. The leak may be somewhere else and just dripping there. If it is coming from the joint you suspect -- where the water pump hose connects to the steel heater pipe -- I'd remove the hose and really inspect the end of the pipe and its bead for corrosion, out-of-round, dents, etc. If the pipe is round and smooth, with a smooth/round bead all the way around, and if the hose is new and healthy, that connection should seal up no problem.
Its not leaking from the pipe its leaking from between the hose and the actual waterpump body, so the hose isnt sealing correctly towards the pumpbody. I know 100% its coming from there, I can clearly see a wet trace coming from there with a drip in the end. The hose is also not wet further up, so its not coming from the pipe connection.
Also from what Ive seen and measured on my old pump, the actual fitting in the waterpump isnt round, its infact oval by over a millimeter. And I thought germans were found of high quality engineering....
Wait, I thought all 951s are cursed. Maybe it's just the owners. Anyway, I think it's almost always better to fix a car before selling, especially if you can do it yourself. But once you fix it and can drive it some, you might remember why you've owned so many over the years. They're special in a way that is hard explain, but a 951 that is boosting, braking and handling well is a lovely thing. And your car really looks beautiful!
Its not leaking from the pipe its leaking from between the hose and the actual waterpump body, so the hose isnt sealing correctly towards the pumpbody. I know 100% its coming from there, I can clearly see a wet trace coming from there with a drip in the end. The hose is also not wet further up, so its not coming from the pipe connection.
Also from what Ive seen and measured on my old pump, the actual fitting in the waterpump isnt round, its infact oval by over a millimeter. And I thought germans were found of high quality engineering....
Is it new, or old and crusty? And how about the hose? New? That's not a particularly problematic joint normally, so something isn't quite right there. A mm out of round should still seal, but casting artifacts (lips, seams, etc.) might explain it if it's a new pump? If it's an old pump, I had success doing this once (on a mercedes ironically).
Its not leaking from the pipe its leaking from between the hose and the actual waterpump body, so the hose isnt sealing correctly towards the pumpbody. I know 100% its coming from there, I can clearly see a wet trace coming from there with a drip in the end. The hose is also not wet further up, so its not coming from the pipe connection.
Also from what Ive seen and measured on my old pump, the actual fitting in the waterpump isnt round, its infact oval by over a millimeter. And I thought germans were found of high quality engineering....
Germans may be fond of quality engineering, but sometimes the Chinese aren't. Are you sure the pump is not aftermarket (not that I'm condemning it, I use them). Also, I believe that bit of hose in factory form has a larger diameter on the pump side? Maybe check to be sure someone didn't try to use a generic length of hose.
Is it new, or old and crusty? And how about the hose? New? That's not a particularly problematic joint normally, so something isn't quite right there. A mm out of round should still seal, but casting artifacts (lips, seams, etc.) might explain it if it's a new pump? If it's an old pump, I had success doing this once (on a mercedes ironically).
The old pump I took off was corroded, which is why I changed it from another one I had. The one I put on I took from my other 951 that was intended to get an LS since its a stripped out racecar shell. That pump looked brand new, and likely was when I bought it. Have no idea if it was a factory Porsche unit but it wasnt leaking in the other car.
Germans may be fond of quality engineering, but sometimes the Chinese aren't. Are you sure the pump is not aftermarket (not that I'm condemning it, I use them). Also, I believe that bit of hose in factory form has a larger diameter on the pump side? Maybe check to be sure someone didn't try to use a generic length of hose.
I dont know if the new pump I put on is aftermarket or not since it was installed in the other 951 I have, it wasnt leaking in that car thou. The old pump I took off that was leaking in the same place Im pretty sure was factory from when the car was new.
I bought a new hose actualy, so its a new hose on it now and its still leaking. And yes it is bigger in the waterpump end.
Im going to try and get a hoseclamp that is wider, I think the one I have now is 9 mm and I think there are clamps that are 12-13mm. On my N/A 944 it has a wider clamp. Other than that I could try a silicone hose maybe that seals better, Im just kind of reluctant at this point to drain and refill the coolant again.
Im still kinda contemplating why its only leaking when sitting. Its not leaking at all when driving and when its hot, it takes a few days sitting cold before it starts dripping. And for the life of me I cant remember if I changed the hoseclamp to the upper hose back when I changed the big radiator hose. I have a bleeding suspicion that I did because it looked so rusty.
It might be a bit far fetched but Ive started developing a theory that the clamp looses its clamping force, like it skips a thread when it gets hot but it seals because of the heat expansion and then starts leaking once its cold. Because every time Ive seen it leaked Ive rechecked if they were lose and Ive always been able to tighten them again, even thou they were as hard as I dared tighten them before. It could ofcourse also be that the clamp is digging further into the hose. I have however retightend the hoses now without starting the car, Im gonna let it sit for a few days now and see if it leaks, if it doesnt leak now it will be interesting to see if it leaks after a heatcycle, if it does then its probably the clamp.
Dunno if its important to the story but Im using the clamps I got from a silicone hose set I bought from Lindsey racing years ago for my other 951.
Take a step back, walk away from it for a bit, I have had 5 951s and still own three.. belive me I have had some issues kick me around .. Usually after thinking about it for a day or two the answer presents itself.. I wouldnt rule out the fact that the pipe over the maifold has a crack in it... Consider P.O. and their ignorance in coolant selection as well.. Ive seen some pretty crappy coolant tanks in some cars, The corrosion is evidence of that.. Id replace that pipe over the manifold..
Consider also that once a silicone hose get ANY sort of cut or rip it makes is very weak..
And if all else fails.. Dont burn it.. Tap the hole put a pipe plug in it.. delete the heater and turn it into a track car..
I feel your aggravation. I had once used what I thought was a good water pump on my 944 and found the same deal you have. Water pumps are cheap enough now to save yourself the unwanted stress and anger of using an old one. I have 7 944’s in my yard so like you and many others we do understand. So you know what to do, that’s better than not knowing. You just got to do it. Don’t think about getting mad. That never helps. And these cars are old. Just go with the flow. This to shall pass and you will have yourself a nice 951. I only wish I had it as easy as you do now. But it is what it is.
Also Tom gave you the best advice. Get a coolant pump tester. I have a Matco one and it has saved me literally on every coolant system I’ve ever worked on. You would be surprised where coolant can leak from.
Last edited by Humboldtgrin; 10-28-2020 at 02:49 PM.
So I just wanted to give an update on how things are coming along with this car.
I have decided to give it another chance. I havent been able to work on it because I havent had enough space in my garage, but I managed to sell a shell from another car today and moved this car into a good location to work on it. I still need to get another car out of the way before I can totally go to town on it but atleast this time the car is in a good spot, its not in the way, so I can take my time and do it slowly and correctly.
My first plan of action is like some of you have mentioned to get a pressure tester so I can pinpoint exactly where the leak is coming from, since it seems like its no longer coming from where I originally said. However Im still fairly certain that Ive gotten a bad batch of hoseclamps, so I will also goahead and change all hoseclamps to new, and change all waterhoses that doesnt look perfect
After Ive gotten that sorted there are a few other issues to fix. There is too much play in the gearlever, theres a short to the reverselight and it keeps blowing the fuse. I need to repaint the rearviewmirror stalks/cover/holders. Theres also a slight oilleak that Im pretty sure is coming from the drainplug since someone drilled a hole in it to fit a temperature sensor that is no longer connected.
After that the car needs a good clean and polish.
I will update regularly but it will be some time before I can start working on it properly, as I have another car, an 87 N/A that Im waiting on a fuelline for so I can move it and I wont get that until mid january.
Floofz,
Interesting read. You are obviously pretty intelligent and a good technician. As a mechanic myself, I find there are times when I am fed up with being a problem solver & I just want things to go effortlessly. When I feel like this, I lose patience & do not think clearly.
Now that I'm in my forties I realize that I only want one project car. More cars equals more stress.
You have a beautiful turbo and really this is a minor obstacle. You got this.
OK - heres an off the wall thought. if you did anything with the hardware that mounts the coolant hardpipe 'elbow' to the cylinder head then you may have used a bolt that is too long. the bolts for that elbow are a special type so that they don't hit the head. if you used the wrong ones it will slightly lift the elbow.
the other tip for pain in the *** coolant leaks is to use a pressure tester to pressurize the system - that way you can look for leaks when its cold and not burn yourself!
10-27-2020, 12:43 PM
The story about the cursed 951
