Loss of coolant and overheating

[veetee500]

Can anybody help i have a 1996 bongo 2.5td diesal with air con i seem to be losing coolant when i use the air con and the engine starts to overheat when i dont use the air con everythings seems fine it takes quite a few miles before the coolant loss has an effect any suggestions ..........thanks.

[Bob]

Don't know what the problem is, but I recomend not driving it until it is sorted. If you blow the head it could be £1300.

If you let us know where you are someone local may be able to help or recomend a local expert.

Good luck.

[francophile1947]

Welcome to the madhouse
What are the actual overheating symptoms? Is the coolant level going down in the expansion tank? Any smoke or steam from the exhaust?
Many people have thought they had a coolant leak when using the aircon - in fact it was just normal condensation.

[veetee500]

Thanks for your replies i am based in NW Kent there is loss of coolant from the expension tank i had the system checked at last MOT by a local reputable mechanic who could find no evidence of coolant loss however i started to use the heater and aircon recently and it seems to result in loss of coolant. I have topped up the system and all seems ok now. There is no vapour with the exhaust gas and no evidence of water in the oil and engine starts ok and runs fine doesnt feel like a head gasket problem. I have tried runnin it without the aircon and heating on and so far all ok i am checking the hoses again for leaks. As suggested reluctant to use the vehicle until i can find out whats happening. Thanks for your help.

[veetee500]

Hi - I think i have found the leak a pinprick hole just on the air bleeding pipe checked after reading the recommendations in overheating and yes its leaking. In tend replacing it and using jubilee clips will i have to drain the coolant down to below the level or is there another way you can recommend thanks for your help i hope this solves the problem maybe the use of he aircon had nothing to do with it.

[Peg leg Pete]

If it is the bleed hose you intend to change, you may be able to replace it without draining the system, It requires a nimble change to avoid losing too much coolant I did mine by having the new hose ready to fit with a funnel fit to the end that you bung, Remove the old hose and block the coolant flow from engine with a finger So do this when engine is cold Have a jubilee or original clip off old hose placed on new hose, if you have a helper, get them to raise the funnel end up, then remove finger and quickly pop on new hose secure and then pop a little diluted coolant into the funnel and back fill, you fill have to keep hose raised, remove the expansion cap and check the level of coolant in the expansion tank, when coolant level is just a little above full level mark, re-fit the cap and then start the engine, carefully raise and lower the bleed hose a few times to expel any air, stop engine and carefully fit the bung, make sure it is a tight fit, should be o.k. to run, keep eye on level of coolant and that heaters are running hot, Well it worked for me