Head Gasket

[wishbone]

i have an 03 115bhp sharan with 170k on it. timing belt and pump done last march and turbo in september. changed faulty water temp sensor a while back but recently there are a few drops of oil? in expansion tank. there is pressure in tank after a run and it will blow out a bit of coolant when i take lid off tank though not much.heater works normal. aux  heater hasnt for years  and lately aux pump isnt working.any suggestions or simply early head gasket trouble.thanks for any replies

[daddyfixit]

is it losing water?  or only when you take the lid off ?

 

dip the oil to see if the oil level has risen (water leaking into sump)

 

system pressurising is normal due to the coolant being heated, usually about 1 bar (14psi)

 

aux pump keeps water circulating when engine is switched off to reduce afterboil, also would reduce any excess pressure by allowing water to travel through aux heater to remove any air locks caused by inoperative run-on pump.

 

1. get a coolant "sniffer" test done---this will check for combustion gases in the water system indicating a leak.

2. get a set of brushes for the run on pump, takes about 2 hours if you follow the guide

[wishbone]

not using coolant but brought it for a 40 drive tonight and was about 75deg on gauge and when i turned blower to 3 temp went to 60deg. only by leaving it ticking over for 20 mins and heater on cold when i came home did it rise to nearly 90.lot of pressure on top rad hose and warm.Bottom hose cold and no pressure.Undid expansion tank lid slowly no coolant came out but pressure was released. And top hose pressure also went.i can see pink coolant trickle into expansion tank through small hose.also tapped aux water pump after turning off ignition and it ran for almost 3 mins.hurry up amazon with the brushes.i not sure exactly all it does but better have it working me thinks.

Edited February 25, 2014 by wishbone