Car getting hot after rebuilding front end...

[MK3 Menace]

Hi all,

Like i said in another thread I had a small shunt that involved rebuilding the front end. Replaced slam panel, crash bar and fitted a Vento front end.

I thought I bled the system ok but took it for a small drive last night (about 5miles) and the temperature rose to 100. Its normally solid as a rock on 90.

I let it cool and popped the expansion tank and it coolant promptly spilt out the top.

So I went with the procedure I was advised and ran it without the cap on and fans on full to try and bleed to system some more.

The car did spit a few bubbles out and water did tend to rise high and low in the header tank.

I switched it off after a while as the water looked to be boiling although the gauge consistently read 90 and i was worried about the engine cooking.

The fan never kicked in at all and the fan motor felt cold.

Top pipe on rad was warm but bottom was not so much.

So my conclusion is that the thermostat might of failed or I have a blockage somewhere.

I am going to removed both pipes off the radiator tonight and run a hose through as my mate suggested and see if there are any blockages.

If not, do you think it was just a case of me not bleeding the system properly?

I really don't want to have to replace the thermostat or water pump unless I have to as I know the location is an arse.

If it is a fan of the fan not kicking it, is it worth me bridging the connection? How easy to do?

Also, I have the blue header tank cap so I think that should be ok.

Any advice or ideas appreciated.

Thanks,
Dan

[Gash]

If its over heating it could be a case of that you didnt put enough coolant in there to begin with.
if you just used water instead of a mix then this would also cause it to heat up more (although not loads)

strange that the fan didnt kick in though, but have you got a single or twin speed? if its sitting at 90 i may not kick in until its been sitting at 90 for a while.

[Gti_Jamo]

Chances are its the thermostat stuck shut or not opening fully. Common failure. They are not too bad to change. Few bolts to remove steering pump out the way and you have good access.

[MK3 Menace]

I am starting to think I may have been a bit stingy with the coolant. I am going to drain it all off later and start again.

It has two fans down there connected off each other via a belt but didn't know if one was for Air Con or something.

I'll try again with coolant and then will tackle the thermostat if its not kicking the fans in still.

Left the car at 90 for a good 10 minutes I reckon and no fan...

[VR6_Wherry]

have you ran the heaters on full in the car too? Try that as well.

[MK3 Menace]

Yeah had the heaters on full when I had to cap off last night to see if i could extract any air out of the system.

I think to be honest thats what helped the car stay on 90 while stationary.

[Gavv8]

I am starting to think I may have been a bit stingy with the coolant. I am going to drain it all off later and start again.

It has two fans down there connected off each other via a belt but didn't know if one was for Air Con or something.

I'll try again with coolant and then will tackle the thermostat if its not kicking the fans in still.

Left the car at 90 for a good 10 minutes I reckon and no fan...

That doesn't sound right..

[Deano2711]

I had a faulty temp sender which meant mine was reading 90 on the guage when the car was overheating. This could explain that and the fan not kicking in. Cost me £8.75 from GSF and thirty seconds to fit.

[MK3 Menace]

I am starting to think I may have been a bit stingy with the coolant. I am going to drain it all off later and start again.

It has two fans down there connected off each other via a belt but didn't know if one was for Air Con or something.

I'll try again with coolant and then will tackle the thermostat if its not kicking the fans in still.

Left the car at 90 for a good 10 minutes I reckon and no fan...

That doesn't sound right..

Under the slam panel are two fans side by side, they have a small belt that drives one from the one with the motor. I can show you a pic if you like as I got the old slam panel I took off to hand...

[MK3 Menace]

I had a faulty temp sender which meant mine was reading 90 on the guage when the car was overheating. This could explain that and the fan not kicking in. Cost me £8.75 from GSF and thirty seconds to fit.

Where does temp sender locate as it could of been something that was damaged or I missed when putting it all back together...