Overheating Problem - Any Ideas?

[AmenToThat]

Firstly can i say thanks in advance for any help offered.

I have got an overheating problem on one of my cars (i seem to be collecting broken cars) that i have been for a while, but have been unable to track down. However i did notice something today :-

The coolant hose to the inlet manifold seems to get hot quickly and seems to have coolant flowing through it, but the coolant hose going to the heater matrix (and eventually the thermostat) seem not to get hot very quickly at all which is worrying.

Does anyone have any ideas as to why this is happening and what could be causing this.

Here is part of the growing list of things that i have checked.

- thermostat checked and changed for a new one
- expansion tank cap changed
- system flushed as much as possible revealing nothing
- water pump checked, i didnt change it for the spare i have as it was in better condition than the spare and seemed fine

Well that the major things that i have checked.

Any advice would be a great help

[Mutant Rat]

First suspect would be an airlock in the heater matrix, from what you have described.

[AmenToThat]

Thanks, i had thought about an airlock and have attempted to elimate them. But perhaps its time i had a proper go. Maybe its even time to get the copper tube out and bypass the heater matrix.

[Mutant Rat]

AmenToThat said:

Maybe its even time to get the copper tube out and bypass the heater matrix.

Yep, that's my kind of thinking!

Bypassing the heater matrix altogether is certainly the quickest and easiest way to eliminate it as a suspect!

[GreenV8S]

Can you escribe the cooling circuit a bit better? Could be that you are looking at a permanent flow through a (presumably heated) inlet manifold, and a thermostat controlled flow through the heater etc?

[AmenToThat]

Cheers for the help guys....

I will try a few things tomorrow, if i dont get anywhere i will take a pic to explain things better.