bored of scratching my head for the last 4 hours so i'm gonna throw it to you guys see if someone can help me out.

mk indy

2.0 pinto bored to 2.1

kent fr32 cam

standard carb

escort mk2 radiator but been modified from top filler to using a seperate header tank etc.

thats basicly the spec now here's the problem.

can sit with the car idling for 35-40 minutes, not a problem at all.

take the car for a drive, not thrashing it as the engine is a fresh build so running it in steady, 7-8 miles and the temp gauge is up to around 100 degrees and that will doing 50-60mph at low revs so plenty of airflow.

went out today up the A6 dual carriage way, 10 miles end to end, soon as i came to a set of lights as i got back into town temp went straight up to 120 degrees so i stopped, pipes were like steel, headertank was bubbling the lot.

i've tried flushing the system and thats clear, even tried running with the fan removed incase it's restricting the airflow to the rad but it made no odds.

every pipe has a home as i've ran a bypass pipe for the heater etc and you can see the water flowing around the system and back through the return.

whats worrying me too is it uses a little water, only drops from the max to minimum mark but it does it every time i take it out and there are no visable leaks.

anyone gimme a clue at all?

Is it possible to fit the thermostat the wrong way?

thermostat got removed weeks ago due to it being stuck closed!

HI Can you post photo's of how you piped the car . is the head gasket ok ?
Jacko

It may sound counter intuitive but put a new thermostat in this controls the flow rate and provides some resistance for the pump, it can be that the pmp will not move sufficient water without a resistance.

Caber

Either air in the system or connected up wrong. Don't think not having a 'stat should cause all that to happen.

How is it all plumbed in?

This is how mine was fine.

Pat...
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Also, bled the system like this:

1) Mix plenty of coolant + water (50:50), at least 10 litres.
2) With engine cold, fill the bottle (header tank) to max (and repeat as coolant is drawn into the system)
3) Once coolant ceases to be drawn out of bottle, start the engine, leaving the cap OFF the bottle.
4) Run the engine until the fan switches on 3 times, then switch off.
5) Let engine cool (leave cap OFF)
6) Top up the bottle to 'max' mark, put cap on, and start engine.
7) Run engine until fan switches on 3 times, then switch off and let engine cool.
8) Coolant should return to max level. If it is below, then top up to max again and check for leaks. If it is above, air is still in the system, so repeat steps 2 - 7.

DO NOT BLOW INTO BOTTLE!!

(Got all that off someone else by the way) but it worked for me.

Pat...

the system is piped up exactly as in pats diagram but without the heater. i've taken some pictures of the pipework so i'll post them up later.

ran it up witout the rad cap on, once it started getting a bit warm the water level started to rise a fair bit to the point it over flowed, put the fan on and it dropped a bit but no real bubble were coming out or anything to indicate air in the system.

the current radiator i have is only a twin core and i only have a very poorly lashed up nissan micra cooling fan. if i was to increase the radiator to a 4-5 core and fit a decent fan (seen a nice pacet item) would this likely help the situation greatly?

I had a similar problem with mine (although it is a CVH). When i bridged the heater hot water out let to the heater cold water in put to the engine, the hot water from the choke housing went up to the thermostat but didn't open it. Instead it went up the bridged pipe and put hot water back into the engine which resulted in the engine boiling already hot water. Didn't believe it till touched the pipe and felt water boiling in it. Plugging the bridge pipe at either end stopped it.

i had an overheating crossflow, caused by the rad i worked out. I changed to a nice 'modern' polo one, ally core, and now i can run it without a fan at all! It really is that good.

truth be told, i actually messed up the fan wiring, but its the same effect!

Hi

Is the water pump new? And how have you modded the escort rad? there's only a pressure cap on the expansion tank and not one on the rad?

Adrian

Mine had a similar thing a couple of months back and the thermostat gasket was the only thing at fault, all I could find anyway. I have the same basic setup with a 2.0 pinto.
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well thanks for all the replies ppl. spent most the morning messing about with it and still it was useless so took it to a guy that my dad knows who builds radiators. basicly he took one look at it and laughed saying how the hell is a radiator for a 1970's 60bhp escort meant to cool a bored out tuned engine in a car with restricted air flow. (i did point out he supplied the radiator so he stopped laughing so much) but basicly he's spec'd a new raditor which should work a treat and he says it'll solve my problems as he's seen exactly the same before.

hopefully i'll be smiling again by next wednesday when the new radiator is here.