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Just picked up at 957 GTS several months ago with 53k miles. Been noticing the occasional smell of burning coolant on driver’s side, and after 500 miles or so notice the coolant level beginning to dip. So it’s a very slow leak, and in fact when I open the cap to check it occasionally, I can still hear a hiss of pressure releasing in the system, but still a leak nonetheless.
Got under there tonight and took undertrays off and can see evidence where the coolant is apparently coming from. This is drivers side looking up underneath where the header attaches to downpipe/cat section. This is almost directly underneath/to the side of the cylinder closest to the firewall, not against the firewall if that makes sense.
Anyone have an idea of what lies up there around the pink drippy stuff? I know it’s hard to see from photos. Is this possible infamous fitting on cooling jacket (although appears maybe a little further forward than that but I’m no expert); or water pump area maybe? Or is this near where the oil/water separator is seeing how the dealer I bought it from recently replaced it before I got it?
i plan to dive in and repair myself once I figure out where it’s coming from. Right now the leak is so slow it’s not a major issue...yet.
Ordered an endoscope to get in there and get a good look, but in looking at some online diagrams, I think I found the part where the leak is occurring from or near, I just haven't a clue yet what this thing is. I found a diagram that shows it, but no legend to go with it to tell me what this is. #21. What is this part?
Main places where cayennes leak coolant are:
- Small plastic Ts in back of engine near firewall (turbo only) - pita to get to, but if you swap, swap with aluminum ones.
- Coolant pipes (older cayennes, 955, not sure if 957 comes with plastic or metal from factory). replacement with aluminum ones is the fix.
- Thermostat housing - seal goes old and leaks. Fix is replace the seal and thermostat at same time.
- Coolant pipe seals and/or large coolant tube connecting upper coolant pipe to coolant distributor subframe (not sure if 957 come with rubber or aluminum tube for this). Fix is replace seals and/or rubber tube
Good way to PD is get a coolant test kit, which will pressurize system and make any leaks visible. Camera may be limited since there are places it wont get to, but who knows you may get lucky.
Keep us updated.
It’s a 2010 GTS so no turbo, and 957 did away with the problematic plastic coolant tubes.
Got the endoscope and was able to go down from the top again in between the the two coils/plugs against the firewall, looking down below the exhaust manifold. Think I found the source but still unsure exactly what this is.
Going to go at it from underneath again with new scope later this weekend to get a better view of whatever this is and how it can be fixed.
I think I’ve located the source of the leak. Seems to be coming from the same cooling jacket/distributor where others have seen the glue/adhesive fail on the barb, except oddly mine doesn’t seam to be coming from the barb but appears to be leaking around the gasket on the area circled in red. I can almost get a swivel socket up in there to one of the bolts just need to get right sized torx socket to check tightness on the connection.
Previous owner had a full engine out service done by dealer and wondering if they just failed to fully seat the connection. If no luck there trying to tighten it to stop it, I may say **** it and pour a bottle of K-Seal in it to see if it cures it or just keep letting it leak and top it off every 500 miles or so since it has stayed consistent and not gotten any worse over last three months.
Another source of leaks on the coolant manifold (distributes coolant between the two heads) is the #4 plugs. On my '06 the casting had a crack in the casting where one of these plugs bolted in. The fix was to replace the entire coolant manifold. It was done without engine removal.
Re: 957 did away with the problematic plastic coolant tubes.
Not so...there is a plastic tube in the center valley between the water pump and the coolant distributor. Its not as problematic as the GEN 1 engines but there have been failures, P makes a metal replacement.
Re: 957 did away with the problematic plastic coolant tubes.
Not so...there is a plastic tube in the center valley between the water pump and the coolant distributor. Its not as problematic as the GEN 1 engines but there have been failures, P makes a metal replacement.
You are correct. Actually in my adventures with the endoscope the other day it does appear mine was already upgraded to the metal pipe and it even looks like some of the “T” connections in the back of the motor have also been upgraded to metal ones.
You are correct. Actually in my adventures with the endoscope the other day it does appear mine was already upgraded to the metal pipe and it even looks like some of the “T” connections in the back of the motor have also been upgraded to metal ones.
Awesome!
When the engine was out it appears they covered all the failure prone items.
Bringing this thread back from the dead. So has been running great the last year or more with the leak coming and going at times and have just been living with it since it was so small. Just have to check and top off coolant a little every few hundred miles. I think my luck has run out though, and now it is definitely starting to leak a little more. I purchased the Schwaben coolant vacuum fill tool from ECS Tuning when it was on sale a while back so am going to need to dive into it soon to sort it out. I think with it up on a lift I can fit a long swivel extension up to the bolts on the water jacket flange in post #9 as I am about 90% certain this is where the leak is I previously found is and check the tightness on them. Previous mechanics at the dealership had that stuff all disassembled and reassembled again and wondering if something wasn't fully snugged down as tight as it could be.
Bringing this thread back from the dead. So has been running great the last year or more with the leak coming and going at times and have just been living with it since it was so small. Just have to check and top off coolant a little every few hundred miles. I think my luck has run out though, and now it is definitely starting to leak a little more. I purchased the Schwaben coolant vacuum fill tool from ECS Tuning when it was on sale a while back so am going to need to dive into it soon to sort it out. I think with it up on a lift I can fit a long swivel extension up to the bolts on the water jacket flange in post #9 as I am about 90% certain this is where the leak is I previously found is and check the tightness on them. Previous mechanics at the dealership had that stuff all disassembled and reassembled again and wondering if something wasn't fully snugged down as tight as it could be.
Wish me luck!
I wish you luck - but sort of doubt if simply tightening it will fix it. That gasket is a hard fiber one, and I can imagine the reason it's leaking more is it's eroded away more due to the leaking over time. Now - despite what the manual says - it IS possible to replace that manifold (and the two gaskets) without engine removal. I suspect it requires someone young and very flexible who isn't bothered by pain. It would have to be done laying on top of the engine, with your head over the rear of the engine, and after removing the high-pressure fuel pump so you have access from the top. It can be done - the dealership who fixed my '06 did it.. but I imagine some pain was involved (luckily I got them to fix it the last week of CPO coverage.) Having an assistant to hand you and take away tools would also be very useful - especially if they know what tools are.
Last edited by deilenberger; 09-14-2020 at 11:06 PM.
05-19-2019, 01:59 AM
Driver’s side coolant leak
