Last week the Scoob started leaking coolant, you could see it dripping from the undertray and on to the road but stopped when the engine was turned off. I thought "water pump" but the local Subaru dealer thought "coolant pipe" and replaced it. Unfortunately the leak is still there!

I suppose a leak from somewhere like the water pump could find its way down to the outside of a coolant pipe to make it look like the culprit.

Anyway, has anyone had their water pump go on their Impreza? And is there any other more sinister possibility for this sort of leak? I'm due to return the car to the dealer next week and I'm just hoping it's as simple as not tightening some jubilee clip tight enough, but how bad could it get!?

wxman

 

Weatherman,
Get yourself off down to Halfords and buy yourself a new rad cap, take it to bits and drill a bigger hole in it. Shove a bike valve (Cut the rubber to the ID of the rad cap) through it, grease the inside of the bike tube for a good seal. Fill your header tank up, then attach your pressure test valve to your header tank. Take a pair of mole grips or locking pliers with sockets over the ends (so you have two nice smooth large rad surfaces) and clamp the over flow pipe, dont over do it you don't want to wreck the pipe. Slowly "inflate" your coolant system using a foot pump or compressed air line (make sure reservoir has <1.5 bar in it) to about 13 psi (0.9 bar) water should be pissing out of wherever it is leaking, if not slowly up your pressure until it does. I have a split in the header on my rad, doesn't open up until it is warm and engine above 4500rpm (water pump goes at engine speed i guess so massively increased pressure at high revs) and when it opens up out squirts the water, revs drop off it closes and it looks like other rad is leaking!!!

Hope it helps, if you don't fancy making your own cap I have a slightly used one I don't need any more

Regards,

Mike