a friends s2 is having serious overheating probs, we cant work out why, even with both kenlowes on it still gets right up near the red and the water in the header tank bubbles like mad, when the cap is taken off shit loads of air comes out


things we have changed so far;


rad
thermostat
coolant hoses
header tank
pressure cap
Y peice (that goes into the heater matrix) - had a small split in it


while running cool the car drives spot on, but boils up very very quickly... there isnt any sludge in the header tank or in the rocker cover - so the head gasket should be fine?

there doesnt seem to be any water leaks from anywhere either


any ideas???

 

Have you got the fans wired in the the right way.........

 

Things i'd check would be:

As above - Fans are sucking in cold air from the front of the car

Is the water pump actually circulating the water
Or are the pipes DEFINATELY plumbed in correctly

Failing that - i have known that the timing being severely out causing this type of overheating.

Have you done anything to the car before this happened (ie put on a silicone hose ket) or did it just happen one day.

 

poss air lock or headgasket can go between the bores

 

we checked the fans and they were blowing air through the rad - so fine


then we went onto change the head gasket which when we took it off definately looked like it needed changing

but now we cant get it to fire up, it spins over fine, every now and then while spinning over you get a faint pop from the exhaust

while taking the head off somehow theyellow connector plug managed to get caught between the head andthe block snapping some of it so for the time being we have just used connectors - btw what does the yellow one control???

timing has been checked and is fine

petrol is fine


anything else that could bestopping it starting???

 

The yellow plug is absolutely crucial - its the main engine temperature sensor.

You've got the HT leads on in the wrong order i expect if its back firing!

 

also check the water pump fins as the last couple of rs's i've had have both needed water pumps due to the fins corroding off....

 

Just a thought aswell,have you got the wires from the yellow plug sandwiched in with the headgasket?