Porsche Enthusiasts Club Forum

My s2 appears to have developed a coolant leak since being garaged over the winter. It is from the thermostat housing area, where do I start and what is the likely fault?

Is the thermostat at the top of the engine on the S2? if so there is a short section of hose connecting a hard coolant pipe. I have just had a leak in this area on my turbo and replaced the piece of short stepped rubber hose with a part described as for the S2.

The thermostat in an S2 is in the water pump. Is the leak coming from this (the bottom hose) area or is it from the top hose elbow housing on the engine (the one with the bleed screw in it?).

If the former the chances are that the O-ring for the smaller hose on the front of the water pump has gone hard and is no longer sealing. An OPC shall sell this seal and possibly also the plastic elbow fitting.

If from the top hose elbow housing it is either an iffy gasket, or corrosion of the mating surfaces, something which a sealant *may* be able to cure for the short term.

Of course it could simply be a leaky hose, a broken clip etc.

Worst case could be the water pump itself

Have taken some pictures.

it is hard to tell from the pics. IMO it is possibly either the water pump although I would not expect to see it on the pump body (it may be worth taking off the cambelt cover to see what the pulley looks like) or the main lower hose.

If it were me I would be tempted to tighten the lower clip up first to see if there is any change, and maybe clean things up there. Failing that, I would change the lower hose and clip for new items but from a reputable source. In this case I would use either OPC (they weren't massive money for this hose) or Berlyn.

Yes there may be cheaper hoses on ebay but if my Stag is anything to go by they're useless (cheap hoses are the only choice for the car bar going silicone, which did cure my leaks and not result in rubber hoses prematurely ageing).

Replaced the O ring today which has solved the problem.