GT1 Coolant Pipe Prevention / Fix on 2011 GT3RS @ Shark Werks

[Dan@SharkWerks]

Update: Please read our updated instruction and documentation with working images etc here: http://sharkwerks.com/porsche/techni...urbo-cars.html Hi guys, Some of you may be aware of coolant pipe issues on GT1-block equipped models (GT3, GT2, Turbo), where coolant pipes come apart while driving and the rapid loss of engine coolant can cause spins/crashes at race tracks when slippery coolant sprays all over the rear tires. The problem exists on the GT1 motor because there are a couple coolant pipes in these motors that are not a single cast piece: the larger cast pieces have extruded inlet/outlet tubes that are connected using an adhesive. There is no metal-to-metal friction or press-fit to keep these tubes in place, so after enough heat cycles the adhesive will soften/loosen up and the tube will come out of the cast block (with the hose still attached), resulting in a rapid loss of engine coolant. Regardless of how the vehicle is driven, it seems this problem may eventually effect all 996/997 Turbo, GT2 and GT3 models including the 2010+ GT3 and GT3RS. We have heard of many cases of this, and in fact the last time we were at Infineon Raceway, Alex and I were talking to someone about it when the exact problem happened to a 997 GT3 right in front of us -- a large steam cloud evacuated the rear of the GT3 and it spun on the hairpin! Luckily he missed the other cars and the barriers. Here's a video showing how the tube comes apart: You Tube You Tube Here's a diagram showing where the problem happens on 997 GT3 models: Here's a picture from a 996 Turbo's coolant pipe. Both of these tubes you see are slip-fit into the cast piece and fixed in place using an adhesive: We first saw this in 2006 when we started building 996 Turbo engines. In fact, our 996 GT3 suffered from this exact problem earlier in its life. James has a technique for fixing this, something we do for all 3.9L motor builds and any time a GT1 motor is removed from the car. This week we had a 2011 GT3RS (project that was documented earlier) whose lucky owner will have plenty of track time with her. He decided that rather than wait until it might happen, he would rather be on the safe side and fix the problem now, preventing a scenario where the coolant might cause a high speed crash at a local track. The bumper is removed exposing the Shark Werks GT3 Bypass Exhaust: And despite the car's super low mileage, its factory fresh and perfectly running motor is removed from the car: With the motor removed from the car, James locates each of the potential problem areas and drills a small hole through the cast piece and into the tube (that normally would come flying out at some point in the future). Then he threads a bolt through both pieces and using loctite secures the bolt in place. This locks the tube together, preventing it from coming apart regardless of heat cycles. The coolant pipes will now act as a single piece. All the tubes are buttoned up... And the motor is lifted back into place, the remaining details addressed. And here she is, now ready for an enjoyable weekend around the track at 8000 RPMs. For more of this car, check out the whole project here.

[MaxAnt13]

Thank you Dan for a great post. How long of job is it to drop the motor and perform this fix?
Thanks again,
Mike

[G997]

The only way to fix this is to Tig weld the joints

[muifast]

Originally Posted by G997

The only way to fix this is to Tig weld the joints

+1 A complete seal around the pipe joints should work better in containing the pressurized coolants.

[Dan@SharkWerks]

Originally Posted by MaxAnt13

Thank you Dan for a great post. How long of job is it to drop the motor and perform this fix?
Thanks again,
Mike

Hi Mike,
This job takes around 2 days of shop time since the motor is removed, fixed and re-installed.

Originally Posted by G997

The only way to fix this is to Tig weld the joints

Originally Posted by muifast

+1 A complete seal around the pipe joints should work better in containing the pressurized coolants.

Hi guys,
There are a few ways to fix this problem including welding the joints. The Excellence February 2011 issue outlines some other options as well. Welding the joints is a more expensive/complex option. The engine is further disassembled: intake assembly removed, power steering pump, water pump casting removed, rear engine mount, the pieces must be put in a kiln using heat to soften the adhesive and remove the tubes, and the castings need to be cleaned, replacement machined tubes must be used & welded. If you have a great welder you trust it might not be a problem but it's a lot more work.

The adhesive around the tube acts like an o-ring to hold the coolant in, the problem we're seeing isn't the coolant leaking through the adhesive, it's the tube completing ejecting from the casting when the adhesive softens.

We have used this pin/loctite fix for the problems since 2006 on cars that had experienced repeat problems, many tracked cars, and none have had problems since. Hopefully going forward we won't see this problem with Porsche cars, with the GT1 block being phased out it's likely that's the case. There's quite a few cars on the road currently with this potential problem.

[pfan12000]

Dan,
The Excellence article said there was an updated part number for the 997 GT3 fittings which was to fix this problem. So you are saying that the 997.2 GT3 (2010+) are still using this part and that is also prone to failure? You would think that the factory would Tig weld the new upgraded parts and issue a recall for the newer cars that are still under warranty.

[Wayne K]

Dan,

Is the hole drilled through the casting and just into the pipe (say half its thickness)or all the way through the pipe such that a leak could arise in the future. Could you also share the size and length of the bolt used ?

[snowboarder54]

I got the SW fix when I had my 3.9 done!! Before the fix I could always smell a slight coolant smell, when driven hard even more so. Since James did his fix, none! I had asked two dealerships about the coolant smell, they both told me it was normal. Put they have been saying the same thing about the RMS leaks!!!

[Dan@SharkWerks]

Originally Posted by pfan12000

Dan,
The Excellence article said there was an updated part number for the 997 GT3 fittings which was to fix this problem. So you are saying that the 997.2 GT3 (2010+) are still using this part and that is also prone to failure? You would think that the factory would Tig weld the new upgraded parts and issue a recall for the newer cars that are still under warranty.

Correct, the 997.2 GT3s have the same type of adhesive-attached tubes (albeit with a different part #), there is not a single cast piece to properly fix the problem.

Originally Posted by Wayne K

Dan,

Is the hole drilled through the casting and just into the pipe (say half its thickness)or all the way through the pipe such that a leak could arise in the future. Could you also share the size and length of the bolt used ?

The bolt was an M4/10mm length I believe. The hole is drilled through the casting and into the tube (to the opening of the inlet/outlet, right against where the coolant would flow). It is sealed with Loctite.

[tssci]

make me sick to my stomach..meaning another thing to worry about with a car I just spent $132K on (2011 GT3). Question...at least looking at the photos, it would appear that with removal of the alternator - and perhaps another bit or two - with the right tools one could drill, tap and install the screws without removing the engine. At least for me, pulling the engine to do this sort of preventative step is beyond what I'm willing to do. Also, can anyone explain why Porsche would make new fittings/castings - assumably to fix this problem - and the problem continues to exist because it is a sealant issue. I should have grown up loving baseball or some other stick and ball game sport...owning these cars is taxing (literally and figuratively).

[Alan C.]

If you leave the engine in the car and drill and tap the holes where would you think all of the filings would end up? Grante the holes are small and some of the debris could be mitigated but not all.

[YoopsRacing]

Porsche needs to step up and fix this with a solution that does not involve epoxy....poor engineering WTF are they thinking

[avbw]

Yes, agree with YoopsRacing. Is there any way that we can at least get a response from Porsche --- either will fix it but do not have solution yet or will not fix it and take your own risk to drive it.

[tssci]

Originally Posted by Alan C.

If you leave the engine in the car and drill and tap the holes where would you think all of the filings would end up? Grante the holes are small and some of the debris could be mitigated but not all.

I would imagine this would be an non-event inside the coolant pipes and areas within the block that the coolant circulates through...the drill and tap process would produce an insignificant/near immeasurable amount of material among gallons of coolant....not engine oil. Seems to me a refill, circulation, drain and refill again would eliminate any concerns. Secondly, I've been given this more thought...how is it that the 'union' can come apart as described - meaning the rubber hose/clamp side would seem to be sufficient in keeping that end of the pipe in place, and on the opposite end, it is held in place by the casting. I certainly understand how a leak could happen, but not the catastrophic event that is described.

[slawek]

the problem definitely exist and it's real just look here Sharky hope you don't maind me posting this I just seen it
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=220730684199&viewitem= &sspagename=STRK%3AMEWAX%3AIT