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If it is leaking from the plastic coolant pipe at the thermostat housing, it is an easy fix.
I did buy the updated coolant pipe and the coolant pipe sealant ring and O-rings, but to replace the updated coolant pipe, you would need to remove the coolant pump. It was summer; I can do that at a later date.
I simply replaced the coolant pipe sealant ring and replaced all O-rings. That was back in the summer of 2021 and it has been dry ever since. See my DIY.
If it is leaking from the plastic coolant pipe at the thermostat housing, it is an easy fix.
I did buy the updated coolant pipe and the coolant pipe sealant ring and O-rings, but to replace the updated coolant pipe, you would need to remove the coolant pump. It was summer; I can do that at a later date.
I simply replaced the coolant pipe sealant ring and replaced all O-rings. That was back in the summer of 2021 and it has been dry ever since. See my DIY.
I'd love to see that DIY. Thank you for your help Alex. Here is another one I found on RL https://rennlist.com/forums/991/1071...lant-leak.html
I looked real close with the service and where the plastic pipe connect to the thermostat it is oozing through the plastic, a crack he thought, Pipe needs to come off hence the 6-7 hrs labor. I do not see how you could replace the sealant ring and O ring without taking the pipe off..
I'd love to see that DIY. Thank you for your help Alex. Here is another one I found on RL https://rennlist.com/forums/991/1071...lant-leak.html
I looked real close with the service and where the plastic pipe connect to the thermostat it is oozing through the plastic, a crack he thought, Pipe needs to come off hence the 6-7 hrs labor. I do not see how you could replace the sealant ring and O ring without taking the pipe off..
The leak is typical of many of the coolant leaks in the 991, that and the famous water pump failures.
I read about the crack in your earlier post. Maybe, but I doubt it. They use a steel collar in each of the three bolt holes in that plastic coolant pipe so that over-torquing of the fasteners cannot cause it to split or crack. Wipe it down to get rid of the dried coolant and have a good look.
To replace the rubber seal at that joint, that pipe does not need to come off. Just follow what I wrote in my DIY.
The leak is typical of many of the coolant leaks in the 991, that and the famous water pump failures.
I read about the crack in your earlier post. Maybe, but I doubt it. They use a steel collar in each of the three bolt holes in that plastic coolant pipe so that over-torquing of the fasteners cannot cause it to split or crack. Wipe it down to get rid of the dried coolant and have a good look.
To replace the rubber seal at that joint, that pipe does not need to come off. Just follow what I wrote in my DIY.
Hi Alex. Thanks again for your help and interest. I did see your DIY which was posted earlier in this thread but wondered if it was a different pipe going into the thermostat in your case. You listed original and updated as Original PN: 9A1 106 215 00 Updated PN: OPB 121 437
My pipe failure and updated version seem to be
Original 9A1 106 238 00
Updated OPB 121 076
It does make sense that it might be an O ring or gasket inside and not a crack the plastic but I wonder if my O ring gasket could be accessed as easily ie without 6-7 hrs shop time to take the back apart exhaust off etc.
The black coolant pipe has a recessed grove in its housing that holds the gasket. It’s thick enough to allow it to be compressed when the bolts are tightened to make a seal happens. I really don’t see how the old one can come out without removing the pipe and if the pipe itself is cracked, which is likely it’ll still leak.
These are the part numbers for the rubber seal. "Updated" in this case means Porsche changed the part number as they sometimes do for no reason at all. I saw no difference in the part itself.
Originally Posted by 96redLT4
Original 9A1 106 238 00
Updated OPB 121 076
These are the part numbers for the plastic coolant pipe or "water pipe" as Porsche calls it in their parts catalog. The "updated" part has been changed in design in that as shown in my DIY, Porsche has added "gussets" at the flange area. I bought the part but to change it the water pump would have to be removed to replace it. It being summer, I wanted to keep my down time to a minimum and simply kept the original coolant pipe and replaced the rubber seal. It has been 100% leak-free since July 2021.
Replacing the rubber seal by itself can be done in an hour if a competent shop is doing it.
I really don’t see how the old one can come out without removing the pipe.
You remove the fasteners that mounts the thermostat housing to the engine block at which point you will have easy access to the seal. Its all shown in the DIY. Super simple!
It’s a stream of thoughts. But yes if you do just the gasket then yes the other process can work. But if the pipe itself has a crack, doing just the gasket may not work.
But if the pipe itself has a crack, doing just the gasket may not work.
Obviously not, but the only way to find out is to lift the car, on ramps at least, have a look at the part, clean any dried coolant residue off the part with a damp rag and visually check while the engine is at temperature (coolant under pressure) and running. I have not heard or read of any of them cracking on Rennlist. Of course the average owner takes it to the dealer and has the leak fixed under warranty (at the time), so how would the owner know. This vehicle is long off warranty.
Really, replacing the seal is such an easy fix. And if you think it isn't, take it to a dealer or shop and pays yer bucks.
Obviously not, but the only way to find out is to lift the car, on ramps at least, have a look at the part, clean any dried coolant residue off the part with a damp rag and visually check while the engine is at temperature (coolant under pressure) and running. I have not heard or read of any of them cracking on Rennlist. Of course the average owner takes it to the dealer and has the leak fixed under warranty (at the time), so how would the owner know. This vehicle is long off warranty.
Really, replacing the seal is such an easy fix. And if you think it isn't, take it to a dealer or shop and pays yer bucks.
It does seem like it is dripping right at the nut through the plastic (although I could not clearly see a crack) so I'll ask the tech to look at the possibility of just checking the ring/seal. I hate to see them take everything apart if not necessary. I wish I was more mechanically inclined to do this myself. Thanks again Alex and DC
Wanted to give everyone some feedback on my leak issue. I think IXLR8 (Alex) above was pretty right on. Appreciated the help from everyone. Ended up replacing the water pipe and o-ring seals but when I looked close could not see an obvious defect in either. Pipe looks solid and as said above has metal casing in the sleeves. O ring was supple and appeared intact so must have been the smallest hairline crack that showed up with heat and pressure in the system. Took the indy shop all day to replace it. Charge was about $955 including parts.
That is because to replace the plastic coolant pipe, they needed to remove so much more including the water pump. Lets hope they replaced all the O-rings instead of re-using them.
03-24-2023, 08:22 PM
