Hi Guys,

Got a silly question to ask as i have got a silly problem!

Running a 1600 pinto from a Cortina (rebuilt) and i am losing water. It doesnt seem to get all that hot whilst running then it will shoot up to ~100 degrees C.

If I then check the coolant level the expansion tank is empty and there is air in the top of the radiator.

The only thing i know to be wrong with my current system is that the thermostat is for a sierra and is fully open by 89 degrees, rather than the cortina ones that are fully open at 102 degrees. BUt i cant see how this would lead to overheating.

It almost as if the rad-cap cant take the pressure in the system and releases too early.

Am suspicious of the water pump not working, but this is brand new!

Any thoughts will be greatly appreciated.

Rich

PS sorry if this post is badly written, am doing in a hurry so i can go outside and move my car as some idiot has parked there sheddy Astra 2 inches off my front end, on a hill!

Sounds like theres loads of air in the system and as soon as the thermostat opens its emptying the expansion tank....have you got some sort of bleed valave in the top of your rad and is your expansion tank as high as it can be - ie. no pipes running above it?? I'd try that and if it fails take the thermostat out and run without one. This is of cource assuming your running the pipes correctly.....Oli.

Thanks Oli,

Rad had a pressure release valve in the top of it that is supposed to open at 13bar.

Expansion tank is the highest point of the cooling system, all pipes run well below it.

have topped up the system once the thermostat is fully open, so shouldnt have any air locks. also fill the system with rad cap off (when cold) so all air is expelled.

Rich

PS on a lighter note the number plate on that bloody Astra has NOB as its letters!

Some Pinto thermostat housings had a small outlet that sometimes had a blanking cap . Make sure the outlet is not bunged up and run a pipe to the header tank. Engine should then self bleed. Might also pay to test for head gasket failure ? even though engine has been rebuilt. Was head crack tested?
PS 13 bar is approx 190 psi

Thanks to everyone who has offered ideas.

However, it seems that i have fixed it!
Have to put a few more miles on the clock and some standing traffic to really be sure but i have just been out for a bit of a blat and she stayed pretty cool.

Ended up finding a small leak on the hose that connects to the inlet manifold. The area also looked a bit wet. Replaced a suspect jubilee clip that would not tighten and now all seems good!

Hopefully i wont be asking this question again!

Thanks again.

Rich