Porsche 996TT/997TT/GT3 Coolant Pipe Quick Repairs
A major issue with the twin turbo since 996, and GT3 since 996 have been the coolant pipes coming apart and resulting in a massive loss of coolant all over the engine and the road behind you. Many clubs have no outlawed these cars on the race track if the pipes have not been repaired. The factory took a metal housing, and GLUED in the water hose connection fitting. Over time and heat cycles, the glue lets go, and the pressure shoots the fittings out of the water pipes, dumping coolant everywhere. To repair all the fittings, the engine needs to be dropped so you can get to them all. There are a couple of acceptable repairs. One is the weld the fittings in place. To do this method, you really need to use thicker fittings as it is really easy to burn though (welding) the OE fittings due to being so thin when trying to weld to the thick housing. The other fix was created by James at Sharkwerks. It involves simply drilling a hole and loctiting a bolt in place to keep the fitting from shooting out. It has turned out to be a quicker, and very reliable repair. The glue won’t fail to leak, it just lets go under pressure. By holding the two pieces together, the coolant stays where it should.
We had this pipe fail a couple of years ago at Hallett. I was behind this GT3 and got to see the front straight into turn 1 sideways.
This is the one fitting that is easy to remove from the car with the engine in. We replaced it with a new fitting, and I found it in my box, so figured I would show the easy and possible trackside repair. With the fitting accessible, a 3/16″ hole is drilled through both the fitting and the insert.
Then the hole is tapped for a 6mmx1.0 thread, and using a liberal coating of RED loctite, screw in a short allen bolt. You want to make sure it is long enough to go through both pieces, but not too long to sit in the coolant flow in the pipe.
That is the easy repair. To get to the other 6 fittings, motor has to come out 😉