S4 Dumping Coolant

[PetrolTed]

My S has ''bubbled'' on turning the engine off for a couple of years now, but recently it''s spewed out its coolant a couple of times when I''ve stopped. The fan is working and it doesn''t appear to be overheating as the guage isn''t heading into the red or anywhere near it. Any ideas as to what I should be looking for? Coolant is puke brown too which ain''t so good (especially since it''s just been serviced).

[johno]

Ted, I would suggest that initially you take off the rad connections and thoroughly flush it through and then flush through the engine block. As for dumping coolant, I would check 3 things in particular. When a water pump goes (which mine did very recently) it starts to leak through drain holes by the bearing. This is the indication of it going. This dumping of coolant was particulary bad when come to stop until finally it just leaked out permanently. Therefor chack for play in the water pump pulley. Next thing I would check is the pressure cap on the top of the swirl/swan neck tank to check that it isn't worn or ill fitted etc. Not expensive. Thirdly if you haven't found a problem by now then double check the hose to pipe connections and jubilee clips. I had a jubilee clip go on one the swirl tank pipes which meant that there was just enough release of coolant (and therefor pressure) to stop but cover the front of the engine without much idea of where it came from. I may add that the jubilee clip was still in place and looked to be tight enough, worth double checking them all. Hope this helps.. Cheers Mark

[PetrolTed]

quote:Thirdly if you haven't found a problem by now then double check the hose to pipe connections and jubilee clips. I had a jubilee clip go on one the swirl tank pipes which meant that there was just enough release of coolant (and therefor pressure) to stop but cover the front of the engine without much idea of where it came from. I may add that the jubilee clip was still in place and looked to be tight enough, worth double checking them all.

Excellent stuff. Thanks Mark. I do recall seeing spray under the bonnet which would suggest a leak.