What can be the cause of this? I'm also having a temperature issue where the fans run all the time while driving. The only time they go off is after letting it tick over a while. I tested the header tank gases for a possible bad head gasket with a parts store tester and it was negative. Is it possible that the head gasket only leaks under boost?

Any input appreciated.

Tommy

 

Tommy;

what engine is this 2wd or 4x4?

the fans should not be running all the time; but they do come on quite frequently if you are running a standard fan switch; what is the temp gauge on the dash doing?

edit: just noticed your in the US - how hot is it where you live?

the oily film in the header tank is a little weird; especially if you've done a fluid test - has the system ever been flushed - are there any other symptoms?

 

I guess I should have given some backround info. The car is a 3 dr with a complete 4x4 engine and turbo. It is however, running a 2wd cooling system set up. It looks like its running the standard fan switch. It cuts in at about 98c during tick over and turns the fans off at about 82c. The only thing that is 4x4 in the cooling system is the header tank. As far as the temperature here... It's been 15-22c.

Tommy

 

Not running an alloy rad by any chance are you? That would explain the fans running on a standard rad switch as well. You might need a green switch if you are - from Stu.

How hot does she run and has the sender been changed of late? They can read lower when they age as a few folks on here have discovered - which can be misleading. Looks cooler than it is actually running.

If there is oil in the water the most likely trouble spot is the head gasket for sure - any water in the oil at all? The tests are for cylinder gasses so if there is a tiny oil leak it might not register as a problem... just yet at least.

 

I am not running a alloy radiator... yet. It's still running the standard unit. The sender in the rad. doesn't look like it's been changed recently.

As far as how hot it runs... It's a little strange. I made a 182 mile trip on Sunday in 26c to 30c outside temps and the car ran at a pretty much steady 87c-90c. The temp. would increase some if I went a little crazy with the boost (21/19 Stage 3 MSD chip) , but would fall back to the above temps on normal cruising.

Tommy

 

I just returned from an extended test drive and wanted to post some info. The temp. remained between 82 and 90c with some spirited boost runs. It seemed the fan was going on an off normally. One thing I did notice when I got back is that the header tank was filled way over the max line and there were some signs of spill over at the fill cap. When I left it was a little above the min. line cold. Is this normal?

Sorry for the newbie questions, but I just got this thing running well after nearly 8 months of fettling with it.

Thanks again to all.

Tommy

On edit- There is no visible water in the oil.

 

As said there should be no oil in the expansion tank, the obvious places are head gasket and modine leak.
It's quite possible to leak oil in water without affecting compression depending of course on where it's gone.
From your description of the water overflowing the cap, I would get a new cap, it may be localised boiling due to lack of pressure in system owing to duff cap seal.
It won't be bothered about those temps at all, the std fan switch is probably about the worst switch ford could have fitted, it just stays on far too long, they only need cycling a few degrees either way of stat temp, this leads to overloading/getting hot issues of the fan circuit.
It is fairly normal for the fan circuits to melt the fuse/holder and relay contacts in the fusebox, for safety rewire it with a decent standalone circuit.
One of the two most essential jobs to do on a cossie of any age is the fan circuit and the pump circuit.
What head gasket did you use, how many miles has it done etc.
tabetha