V6 turbo coolant temperature

[simontaylor]

It is possible to take the end tanks off.
Just bend all the tabs carerfully from the central core, you might need a new gasket afterwards when refitting.
Even if you only take 1 end tank off, you can get a wire into the core to poke out the silt.
I had mine re-cored a good few years ago, your local Radiator shop might still be able to get you a core if you take the blocked one to them. Being half blocked will be a major part of your challenge.

Even if you just put a couple of cup fulls into it, slosh it from side to side a lot and you will get some more silt out of it.

I got a local radiator shop in Ireland to re-core the radiator on mine 4 years ago. The core was available the next day - in a country where the cars were never even officially imported! - so no problem there. Re-core is inexpensive and should cure all your temperature problems. The fins corrode & just disintegrate, adding to problem of rust & other sludge inside. The combination kills cooling efficiency. Mine has been perfect since; steady 90 degrees on the gauge when moving, rising to 95 stuck in Paris traffic on a 29 degree day. Check all the hoses are good.

I sloshed the radiator side to side and a lot of silt came out. I did this until the water was clean. I also cleaned the engine block. I pulled out the plug on the engine block and nothing was leaking. I gave it a good flush and after that, water was pooring through the engine block screw. I will put back the radiator and saturday I will take it for a drive. If it does the same, I will change the radiator. And one more problem: when the water hit 120, the fans in the engine bay were not working, and no warning light was flashing in the dashboard. Shouldn’t the fan in the right side that cools the turbo go on when hot?

I also cleaned the engine block. I pulled out the plug on the engine block and nothing was leaking. I gave it a good flush and after that, water was pooring through the engine block screw.

Just one thing ...... it may be a typo, or translation problem ...... but there are two engine block drain plugs ...... one on either side of the engine block.

Engine bay fans are operated by the two thermostats next to the turbo. A screwdriver across the terminals (not not to earth) should turn them on.
Top one operates the fans and should have the lower value (should be stamped on them) the lower one operates the "stop driving" light on the dashboard.
The thermostats go the opposite way around to the parts book, but this is how the workshop manual describes them working and worked on my car (in fact that was how it came).
If you are is an earlier one, there is an additional sump switch that switches between high and low fans speeds. You'll have to check in the workshop manual for how that system works.

Cheers
lee

Thank you, I will check tomorrow. I only managed to unscrew the left drain plug. The other one is seized and I don’t want to damage the engine block. I do have a spare engine, but I knock on wood.

[simontaylor]

PLUS.... on early cars there is a temp sensor in the drivers side of the sump, When the oil gets up to 65 degrees, the fans will operate at half speed, then when the turbo sensor trips, they go full speed, then when turbo gets really hot, other sensor sets the over-temp warning light on dash. All explained in the WSM.

I put the radiator back, cleaned the system, bleed the system. Still temp stays high. The engine bay fan only goes on if I take the wires out and make a bridge on them(sorry for my english). I guess that the sensor is out. The radiator fan works. Any part number for the temp sensor in the engine bay? But, I think even with the engine bay fan not working, temperature should not hit 110-120 after 20 minutes of driving.

[simontaylor]

You can not get GTA temp sensors any more, you will have to buy something else.
I might have a look for what I bought over the weekend.
Do you have a sensor in the side of the sump, drivers side. If you do, unplug it and connect the 2 terminals together. Then the fans will come on with the ignition and not wait till the oil gets warm (assuming the sump sensor works).

I will check if I have it. The car is 89 and it might not have it

The engine bay fans have nothing to do with coolant temperature.That is controlled by the rad sensor only.
Put your heater to hot setting and see if it blows cold at any point, that will point to a air lock or radiator issue.
From cold you should see a steady rise then a sudden drop as the thermostat opens and the coolant flows through the whole system.
Hard hoses may indicate a gasket leak but it's hard to diagnose via the internet
Check to see if there are any gases in the coolant system.

Took the car for a drive. I made the engine bay fans run for 20 minutes by joining the wires temp sensor. Still the temperature doesn’t go under 110. Last solution is to change the radiator and if that doesn’t work I will take the engine of and change all the hoses and headgaskets

Try taking the thermostat out and test it by heating it in a pan of water. I had a brand new one that didn't open fully and caused very similar symptoms. It's not impossible that you've simply got a bad thermostat.

Alternatively (and just as a temporary test) you can try running with no thermostat. Just remove from the housing, go for a drive and see if you get the same results. Quick, cheap and easy test. Water flow will be at max rate then so it doesn't give an absolute answer but if you're still overheating then we know it's something serious elsewhere.

Once you've ruled that out you can move on to the bigger things - rad, pump and heads.


As Lee said - engine fans are barely a factor in coolant temps so don't worry about them for now. Front rad fan is so check that's working though - but only really for low speed / traffic.

Mini metro radiator fan sensor is nearly identical to the gta engine bay fan thermostat.
Have a look on eBay...remember the one operating the fans is the top one, of it isn’t swap them around.
However as the others have said...the engine bay fans don’t lower the water termperature.
Do the front fans come on?
I have bought a infra red thermometer with a laser indicator from eBay...8 quid. I did this after watching the aa man use one to diagnose what was wrong with another car. You can see how hot the block, hoses and any radiators are...quickly tells you if you have a blockage and if the thermostat is opening without opening any pipes.
Might be worth buying one of those too.
Have you eliminated a faulty gauge or sender already?
If not...this will tell you.

Thank you all for the replies. I tried 3 thermostats. I have an infrared device and I will check it. The problem is that the water goes at 110 after 30 min of driving. At that temperature the water should be boiling in the expansion tank but when i ckecked it, the hoses were hard and very hot, but the water was not bursting out(sorry for the english). Even when the water almost hit 130 on the indicator, the engine bay temp light didn’t came up. I made a bridge on the wires and the indicator works