Taz's Grief

[LandyAndy]

Hi Guys
I got a call from Taz yesterday,his Disco TDi 300 was overheating badly 100ks south of here.The RAC checked it out and suspected a head gasket or crack.
I went down to help them out and we eventually got it to Williams,and this morning the RAC have taken it and Taz to Perth on a trailer.
The symptoms.
Taz says it was running at normal temp then would suddenly go straight up to the red,he was towing a reasonably heavy camper trailer.
I suspect that the leaking exhaust gas(it was bubbling in the header tank) was getting traped at the thermostat and was preventing water fron activating the thermostat correctly????????and giving a false temp reading on the gauge,apparently his EGT was indicating a normal temp.
We removed the guts of the thermostat,it helped but it still ran hot.
Is there a supplementery thermostat on these TDi motors???as it seemed there was pressure still been held elsewhere in the system whilst the header tank was open.
It was using a lot of water,drive for 10/20 minsat 40 to60ks allow it to cool and refill,there was no obvious sign of water loss except fom the cap.
We tried combinations of no cap/loose cap/tight cap all the same,opening the thermostat helped marginally.
Taz is returning later on this morning to collect his wife and kids and camper trailer in another vehicle.
Andrew

[DEFENDERZOOK]

<span style="color:blue">you sure there is no blockage in the radiator......?</span>

[LandyAndy]

Not sure Zook
It was bubbling a fair bit thru the header tank,even after bleeding as much air as we could.
I suggested to Taz to get the system pressure tested to see if there are any leaks.
Andrew

[George130]

My TD5 still does that. I top it up every now and then. Passed the pressure test with flying colours. And yes I bleed it each time I top it up.

[DEFENDERZOOK]

<span style="color:blue">sounds like compression is getting into the cooling system and causing an air lock....



is the water pump working properly.....?</span>

[Hellspawn]

[quote=DEFENDERZOOK]<span style="color:blue">
is the water pump working properly.....?</span>

Yeah I'm wondering the same whether it's boiling on the back cylinders due to lack of water flow. Though that's more an inline six problem.

[DEFENDERZOOK]

<span style="color:blue">its gotta be something simple......
it always is.....</span>

[Taz]

Thanks Folks

I drove it down the hill to the nearest Natrad center and they tested for exhaust emissions in the header tank - the result was negative https://www.aulro.com/afvb/ https://www.aulro.com/afvb/ and they suggested that the gurgling thru the header tank could be explained by a blocked radiator. However they also explained that the test is not always 100% confirmation that the head doesnt have a fine crack in it https://www.aulro.com/afvb/

I was not looking forward to removing the head, so I'm keeping my fingers crossed it's just the radiator. They will look into it next week. I will asked them to check the water pump flow also.

I think that I will be very lucky if it is just the radiator and no other damage is done. When I called the RAC the engine was smoking and I thought it was seized. I was watching the temp guage like a hawk at the time and it let me down as it never exceeded 60% - perhaps an indication that the rear cylinders were starving of coolant but the coolant temp at the guage was ok?

I must thank LandyAndy for his help, his advice, his hospitality and the oppertunity to sample his home brewing skills!

[Tiny]

Sorry to here Taz - hope you get things sorted out.

I'll catch you next week.