Leak at the expansion tank - possible fix

[Beecher]

:D Many folks have warned about the expansion tank being a source of leaks. I found some crusting under the cap of my 2003 TT. I had the new style blue cap, but I figured it must be leaking and called Sunset Porsche for a new one. They advised me that the pressure relief valve could also leak and sold me a set of O rings for $1.50! Not all P parts are expensive. I went ahead with a new cap as well.

Here's how to change the O rings. Unscrew the 10mm nut that holds the front of the expansion tank to the fender well and gently pull the tank to the right to get clearance to reach the ring of 7mm bolts around the top of the relief valve. Remove the bolts, then lift off the valve, it will come off in two pieces. Open the valve to lift the plunger and lock it open so it can be easily replaced, then remove the large O ring and replace. My small O ring was missing, so I put in the one from Sunset. Put the pieces back together and screw the valve back on to the top of the tank. Since the 10mm nut securing the tank is on such a long shaft, I installed a spacer between the nut and the tank. It saves a lot of wrenching in a tight space. Top up with Porsche coolant and you are done! Remember to close the bleeder valve.