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View Full Version : oh dear ... i suspect the Head Gasket



jackal2513
Thursday 23rd June 2005, 19:42
wife had to get recovered today

steam started to come from the bonnet. The AA came and could not really detect much and recovered the car home.

Everything appears normal including 3 oclock temperature gauage, no oil water mixture apparent anywhere, fan working ok, no leaks, no exhaust smell from header tank. The only symptoms are:

1. pressure in header tank/bubbling leading to steam escaping eventually
2. water forms inside the lip of the exhaust when idling


the other thing is the AA man said he fired an IR temp gun at the temp sender position and got a reading of 106c whereas the dash temp guage is reading normal at 3 oclock. So maybe the sender is screwed as well.

I take it that this can only be the good old head gasket ? I can check the thermostat but can't see how i'd get water in the exhaust if just the thermostat was faulty. If anything the thermostat could be faulty which lead to the HG failure in the first place masked by a faulty temp sender ?


any tips ? or ideas how much a HG replace will cost me at a volvo independent ?


thanks


Rich

Not_Gwaredd
Thursday 23rd June 2005, 20:46
You deffo don't have a leak, no? The temp gauge will always read normal or under when the car has no water in it, because *drum roll* the sender has no water to measure the temp of. It's a bum design really, the temp gauge only really has any benefit if the fan fails.

I can't see why steam would come from the bonnet if there are no leaks, as IF the HG has failed, then the leak would be internal & steam would exit the exhaust pipe & the water level would drop in the header tank, though if ther is A LOT of pressure in the header tank, then it's possible that the HG has gone between a water way & bore, not water way & oil way, hence no oil & water mix & I suppose hence the steam under the bonnet if the pressure is great enough in the header tank.

What I would be inclined to do is to refill the sytem with water & coolant, bleed it thoroughly, then tighten the cap & leave running untill the fan cuts in. This way, you'll be able to see if there are any leaks or if there is steam coming from the exhaust after it's up to temp. If the water smell & tastes sweet that's exiting the exhaust, then it's coolant & is a HG failure.

I'm suprised the AA guy didn't do a pressure test there & then, they are usually the best method. The temp reading from his gun isn't too alarming. Cars tend to run a normal operating temp from anywhere around 80deg to 110deg depending on engine, plus it was a very hot day today. When a cars temp goes into the red, the water temp is usually around 135deg+. I should know, have the scars to prove it.

Good luck,

Gwaredd.

splatt
Thursday 23rd June 2005, 21:03
bubbles in the header do indicate a head gasket leak normally, as the engine does its stuff it pumps air into the coolant hence the bubbles.
Pressure test is the best way to be sure.

jackal2513
Thursday 23rd June 2005, 21:41
thanks guys

i ran the car again, definitely no leaks

the water that collects in the tailpipe is tasteless, definitely no trace of coolant and there's no smoke or steam coming from the exhaust of any sort

removed the thermostat and try as i might, could not get it to open in a pan of boiling water so that looks broke and has obviously been shut tight preventing the engine being cooled properly. I guess this must have happened today though because theres been no sign of steam or overheating up till today. There is water the other side of the engine (when i took the thermostat off) so I'm still at a loss as to why the dashboard temp reading is normal ?

i guess the question is whether this was the initial problem and has subsequently caused HGF or not. Personally I cant see how just a faulty thermostat would cause so much pressure in the header tank ?

siamblue
Thursday 23rd June 2005, 22:27
I have said this before Jackal on the 0 service change the thermostat, It's crazy to do a coolant change and not replace this cheap part, As the consequences are very very costly.

jackal2513
Thursday 23rd June 2005, 22:36
yep, will bear that in mind
only got the car 3 weeks ago though

LucieDom
Monday 27th June 2005, 13:36
Hi there, I dont know what model you have but we had the exact same prob with our 2001 s60 t5. Thought it was head gasket, i cried for days then took it to volvo.... there is a recall on s60s and maybe other models for the fan module etc they took it in replaced the whole lot and didnt charge a penny. You can ring any dealership and ask but be warned they dont like to broadcast it and the the end date on the recall is this thursday, 30th june,so better get in quick otherwise its about £600!!!!

jackal2513
Monday 27th June 2005, 20:45
thanks all...

replaced the thermostat

all now working ... done over 150 miles in the car so all looks good

pretty chuffed of course, only cost me 6 pounds to fix.