Ive just change my engine & just had new head gasket & water pump, I am getting a little bit of a drip on header tank cap after doing a short journey, all heaters are working fine, no pipe swelling anyone no whats it can be ???? cheers lee

 

Could it be just the header tank cap leaking ??

 

I have just replaced my header tank, the neck of the bottle had really small crack in it but it was enough for the water to seep out during a journey and make a complete mess of the top of the tank.

Subaru dont make the metal ones anymore, they now do a plastic one that replaced it.