Temp guage high, blowing cold air

rlj86 said:

Just happened again and there is the slightest of leak, just little bubbles from behind what looks like the bracket to which the water pump is bolted to.

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P gasket?

A guy at work has mentioned p gasket today, would this cause the symptoms I have described or could it be head again due to radiator?

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Sorry I can't help you on that, I'm a petrol man. I just know that is where the P gasket is on a TDi. Hopefully somebody else will be along to put you right.

P gasket has gone, viscous fan just about gone and tad knackered, also had an airlock too, airlock done, rest to sort on days off, the joys!

Right, I am really starting to get pi$$ed off now! So far I have done:

Head gasket (head skimmed and pressure tested)
New radiator
New p gasket
New viscous fan coupling,
New stat

Still overheating :-( any suggestions?

Previous posts indicate you have also changed the Water pump as well , assuming all the parts you changed are still OK and were not faulty when changed there is not much left .
Is there anything in front of the radiator that blocks or reduces air flow through it ?
There is also a thermostat in the bracket thing that holds the oil filter this opens and alows engine oil to flow to the oil cooler in the radiator. This should open before the water thermostat and will make a difference to the the engine block temperature if it is slow / late or does not open at all . The other things are air locks caused by very small water leaks through joints etc .
Regards Jonathan

Yes, forgot about water pump being done too! Rad, viscous coupling and p gasket were only changed on Friday afternoon, should the airlock happen so quickly? Could the head have gone again, realised rad had gone after head was done due to still overheating? If so, is there any way of of having it tested without stripping it down? No obvious sign, oil in water, water in oil, water in exhaust etc. Would new hoses be worth trying invade of pin prick holes leaking under pressure?

Well it is possible ? A garage can pressure test the cooling system , ie fit a guage to the header tank and pump a little air in it and see how much it drops in presure over a period of time which will confirm any leaks or a possible head gasket problem and they should do a sniff test using a special indicator dye in a glass tube on the coolant again via the header tank which is the best test to see if any exhaust gasses are present which will confirm if there is a head gasket problem if it fails.
Check that the Thermostat is actually working , by the pan of hot water method . Genuine ones are made by Waxstat . Make sure the heater controls are set to hot when topping up the coolant and via the radiator and thermostat housing and squeeze the radiator hoses to help circulate the coolant and move any entrapped air while topping up . The system should self bleed when the engine is running that is what that little round disk/valve is for that is connected to three pieces of pipe that is at the top of the cam belt housing via the thermostat housing and the header tank and the top of the radiator. This could posibly need changing as well . Other new hoses and Jubilee clips are a possible next to change but best to check for damage and tighten everything and then go for a sniff test and a prssure test . Regards Jonathan

I removed the small pipe from the thermostat housing to the header and turned the engine on. Water is is coming out in spirts and bubbles/foam is coming out and spewing out as I would imagine

air lock. drain system an refill as per manual

Right guys. Sorry to keep bringing this thread up. Had the glass tube on and dye stayed blue so in theory head not gone. Been fine for a couple of weeks but temp started to rise again today. The difference this time is that I didn't lose warm air on the cab like before and when I turned to heater on full and to the end of the hot dial, the temp gauge instantly started to drop and settled back in the middle and stayed there. So what's different this time?

Bump

Anyone?

Bump

hi pal when you refill the coolant system where do you fill from. Best place is the bung ontop of the stat hosing as its the highest point. I normaly fill with a bit of boliing water just to make sure the stat opens. Also keep the coolant bottle cap on when filling, otherwise it will just flow in there and not into the engine and rad. You should see the air bubbling out of the stat bung as you fill. once the stat housing fills and doesn't drain anymore replace bung, and crack open the coolant bottle cap. It should fill, and you may need to drain some out. This is how i do it, and works everytime for me