Turbo Diesel 1.6 Overheating

[FlorenceT25]

Checked the forum but can't find an answer to this one.

Whilst bleeding the cooling system after replacing the rad and thermostat I tried several methods to remove air locks. On standing, the cooling system works fine. The fan cuts in and the needle stays around the middle of the gauge. When driving, the needle creeps up to 3/4. I parked the van on my sloping drive and opened the bleed screw with the engine revving at about 2000. No water or air came out of the bleed screw. It was if it was not pressurised. When the van was on the level, water came out again. Has the water pump had it?

Craig

[FlorenceT25]

Questions.........

I have replaced the water pump. Now water is easily coming out of the bleed screw.

I still have a temperature gauge issue. So I swapped the sender for the gauge with the sender for the electric water pump. The pump started working with a cold engine and the temperature gauge buried itself into the lefthand side of the gauge.

Are these two senders the same? They look the same. Do these results suggest they are both faulty? Where can I get them from if they are faulty?

I have found something similar on VW Heritage but i am unsure which one of the options I need.

http://www.vwheritage.com/vw_act_shop.p ... try_GB.htm

http://www.vwheritage.com/vw_act_shop.p ... try_GB.htm

http://www.vwheritage.com/vw_act_shop.p ... try_GB.htm

Help would be greatly appreciated.

Craig

[VWGeoff]

Did you test new thermostat in water before fitting? I was told by a mechanic even new thermastats stick sometimes, he said he had to return one once to shop before fitting it as it didn`t open.

[weldore]

electric water pump ?
if you mean the senders on the rad then they cut in at different temp degrees so the fan works slow on one and faster on the other..i think

the sender for the guage on the dash is on the engine at the back of the head..if you earth the connector to the engine it should shoot up to the right side of the guage,then you know its working.

praps ive got what your saying round me head though

[Oldiebut goodie]

The turbo has an electric water circulation pump that runs on after engine switch off.
Switches at 104 degrees.
Both switches available from Brickwerks.

[FlorenceT25]

Thanks for the replies.

I have bought a replacement sender and it reads even hotter than the original

The previous owner had used only one belt to cover all 3 pulleys. I have replaced this with 2 belts as designed.

After experimenting with swapping the senders for the electric pump and the temp gauge, I figured out one was a switch and the other a thermister. I bypassed the temperature sender with a 100 ohm resistor as suggested in a post I had read somewhere. The gauge gave a reading smack bang in the middle.

After doing over 50 miles in the van today including some long and demanding hills, the engine did not smell or feel excessively hot, the radiator was reasonably hot all over, though not hot enough for the fan to cut in. Water, not air, came out of the bleed screw.

I may just check that thermostat tomorrow to be sure, or even run the van without one for a while and see what happens. What do you think?

[Titus A Duxass]

I had similar symptoms it turned out to be a cracked head which is not uncommon with the JX motor.
Exhaust gases could getting into the cooling system and blowing the water out.

You can get a sniff test done at some garages, this will tell if exhaust gases are present in the cooling system.

[FlorenceT25]

Well I think it is all sorted now. It turns out to be an air lock causing the grief. I pre-filled up the hoses connecting to the electric water pump. I also spent a lot of time squeezing the hoses when both hot and cold. I parked the van at very steep angles, forwards and backwards. I bled the radiator until the cows came home and were harvested for burgers

I have driven around in her most of the afternoon. The gauge read 1/2. I took her up a steep hill for 2 miles. She warmed up a little but nothing like as hot as she did.

Not a drop of coolant lost, so the dreaded cylinder head probs are not the cause. My last Vauxhall Astra estate died that way

Touch wood that my trip to Holland starting tomorrow, has no van issues

Craig

[Titus A Duxass]

[FlorenceT25]

Back from Holland and she drove like a dream. No misbehaviour or anything. She even pulled 70mph on the motorway when she had to.

Well pleased

[kit]

Good news mate.