Isuzu Engine Cooling Problem

[Living the Dream]

Hi All

 

My neighbour is having a problem with his engine cooling which I think is affecting his caligrofier (spellcheck?) Basically the engine is not heating the water in the cally thing. We have discussed air in the system, we have discussed possible thermostat problem due to the fact the engine overheats for a period when cruising but then the temp drops. At present he finds the only way to run the engine without it overheating when static is with the header tank top off!! I have told him to get someone who knows what they are doing otherwise he will damage the engine.

 

So basically the engine temprature is erratic and the engine is not heating the water in the caligrofier. Any thoughts?

 

Regards

Dave

 

Hi All

 

My neighbour is having a problem with his engine cooling which I think is affecting his caligrofier (spellcheck?) Basically the engine is not heating the water in the cally thing. We have discussed air in the system, we have discussed possible thermostat problem due to the fact the engine overheats for a period when cruising but then the temp drops. At present he finds the only way to run the engine without it overheating when static is with the header tank top off!! I have told him to get someone who knows what they are doing otherwise he will damage the engine.

 

So basically the engine temprature is erratic and the engine is not heating the water in the caligrofier. Any thoughts?

 

Regards

Dave

 

Furthermore the water pump fan belt snapped and they continued cruising for 10 mins or so. I really reckon its get the experts in time.

 

Dave

[alan_fincher]

Not a lot to go on.

 

It's a "calorifier" by the way, although nobody seems in agreement how to pronounce it.

 

I'd say that it is more likely to be a problem with an air lock in the system, than with the thermostat.

 

However running the engine with the cooling cap off is normally more likely to make it overheat, that to stop it.

 

I'd have thought, depending how hard it was being run, going on for 10 minutes after a fan belt breaks is not great, but probably not fatal. It really depends how hot it got after that.

 

Sorry, not a lot of help.

 

You haven't said if it used to work fine, and if so whether anything is known to have happened before it didn't. That might help diagnosis.

[Living the Dream]

Not a lot to go on.

 

It's a "calorifier" by the way, although nobody seems in agreement how to pronounce it.

 

I'd say that it is more likely to be a problem with an air lock in the system, than with the thermostat.

 

However running the engine with the cooling cap off is normally more likely to make it overheat, that to stop it.

 

I'd have thought, depending how hard it was being run, going on for 10 minutes after a fan belt breaks is not great, but probably not fatal. It really depends how hot it got after that.

 

Sorry, not a lot of help.

 

You haven't said if it used to work fine, and if so whether anything is known to have happened before it didn't. That might help diagnosis.

 

Yes it was running fine. I must admit I thought it must be an air block or maybe some other kind of blockage in the system i.e. some dirt build up or something. i have helped him bleed the system and it heated up his water but then it went cool again, that says to me its air. to be honest I really think he should get someone in who knows what they are doing. He is on about changing the thermostat and seeing if that helps.

 

Thanks anyway, I will let you know what it was when its fixed. It may help others in the future.

 

Regards

Dave

[Guest TerryL]

Hi All

 

My neighbour is having a problem with his engine cooling which I think is affecting his caligrofier (spellcheck?) Basically the engine is not heating the water in the cally thing. We have discussed air in the system, we have discussed possible thermostat problem due to the fact the engine overheats for a period when cruising but then the temp drops. At present he finds the only way to run the engine without it overheating when static is with the header tank top off!! I have told him to get someone who knows what they are doing otherwise he will damage the engine.

 

So basically the engine temprature is erratic and the engine is not heating the water in the caligrofier. Any thoughts?

 

Regards

Dave

 

 

 

Furthermore the water pump fan belt snapped and they continued cruising for 10 mins or so. I really reckon its get the experts in time.

 

Dave

 

Could be the overheating caused the head gasket to leak and the gasses to cause gas/air locks or the belt needs adjusting, insufficient flow. What sort of cooling system is it?

[alan_fincher]

Yes,

 

If the cooling and calorifier circuit work OK for a bit after bleeding, but then stop, it would point to gasses getting in from somewhere, so head-gasket seems a possibility.

 

Was the incident of running it with no fan belt before any of this started happening, or did the troubles begin before then?

[rover220]

after 10 mins under laod, with no pump, it almost certainly got hot enough to blow the headgasket. that is most likely causing airlocks in the system, plus youll find that the isuzu's pretty much self bleed themselves if the pipes are routed correctly.

 

thermostat is quick and easy to change so worth doing that before going at head gasket.

[John Orentas]

Hi Dave.

 

There is nothing to suggest that the head-gasket is blown or damaged and generally speaking it there is water in the engine it has not significantly over-heated.. It sounds to me that there have been various additions to the standard cooling arrangement so I would be inclined to take the calorifier out of the cooling circuit and start from there..

 

What evidence is there that it was over-heating at all, if an engine will run with the filler cap removed without 'boiling' it certainly is not getting excessively hot.

 

For some reason whenever there is a suspicion of an engine over-heating every starts shouting "head gasket", if the gasket had gone you are likely to get pressurisation of the coolant, oil in the coolant and/or coolant in the oil, you have none of these.

 

I think your friend is suffering from a hot water system that is not working correctly and somehow leaping to the conclusion that the engine is overheating.

[rover220]

a failed gasket will/can cause airlocks.

 

id not be convinced its the hg but from what hes said i wouldnt be surprised if it turned out to be.

[bottle]

 

Being of the older generation, I had to read this a few times but got it in the end.

 

id not be convinced its the hg but from what hes said i wouldnt be surprised if it turned out to be.

 

I'd not be convinced it's the head gasket from what he's said, I wouldn't be surprised if it turned out to be.

 

Still needs some work, over to Moley.

 

[colin loach]

the head gasket goes , you will in most cases loose power and get water in the oil or oil in the water. sometimes there will be white smoke from the exhaust (steam)when

[Living the Dream]

Thanks for all the comments everyone.

 

Yep Ive been thinking head gasket but I checked the oil and water and there is no oil in the water or viki verki. Apparently the he had the problem before the waterpump belt went. Some one else mentioned that this engine was self bleeding so I binned the air in the engine water system idea. As I said he is going to change the thermostat but if that doesnt work I told him to get an expert in. Im really worried he is making it all worse by running the engine with the header tank cap off. Will let you all know what it was when its fixed for fututre reference.

 

Thanks again for the replies

 

Regards

Dave

[alan_fincher]

Running the engine unpressurised, without the pressure cap on the header tank, is unlikely to damage it, as long as he keeps it topped up with water.

 

However I'm really struggling to see why it would overheat if pressurised, but not if it isn't. That just doesn't make a lot of sense to me.

 

If the overheating predates the running with no fan belt, I'd be less inclined to think head gasket, particularly as none of the other things that might indicate it are present.

 

The engine cooling system may be "self bleeding", but people fitting them to boats are more than capable of poor skin tank design, or silly arrangements with hoses. I still think air lock is favourite.

[Living the Dream]

Hi All

 

And the expert said..........................................."Its the head Gasket"

 

Regards

Dave

[rover220]

if this problem was evident before the pump belt went then its certainly more likely that it is now a headgasket problem, even if it wanst before.

 

is said expert someone trustworthy?

[Guest TerryL]

Hi All

 

And the expert said..........................................."Its the head Gasket"

 

Regards

Dave

 

Do I get a prize or should I wait until it's confirmed?

[John Orentas]

A good Friend of mine had a very smart early 1970's MG saloon.. Driving home from work one day he noticed to his horror that the oil pressure was reading zero.. Cutting a longish story short, a couple of months later and many hundreds of pounds poorer, he set off for a test trip with his now totally rebuilt engine the oil pressure was now reading....... 'zero'.

 

The following day he set off for another test trip, his engine fitted with a new sender unit, he was a further two quid poorer, the oil pressure 25 psi.

[chris w]

.....................the moral of the story being that you've got some pretty dozy friends?

[rover220]

.....................the moral of the story being that you've got some pretty dozy friends?

 

i lol'ed at that