No hot air blowing! Out of things to try?

[bhagatsingh]

Hi

I have a T25 1986 WC Petrol -- which is not blowing any hot air out of the fans.

This lead me to think I need to bleed the rad - so I've been bleeding the rad all day -- no more bubbles comin out of front rad and rad, water, fan all working fine.

I've had a look underneath to see if the cold/hot switch mechanism is jammed (it looks like a small wire being pulled left-right) - but it looks like it's working fine. As it's summer im not too fussed about the hot air - but am I right in thinking I won't be able to fully bleed the thing unless I get the hot air blowing?

Any help on other things to poke at which might get the hot air blowing would be much appreciated! Im driving 9 hours tomorrow PM!

Thanks in advance.

[syncronized]

Is the pipe that goes to the heater valve getting hot?

[bhagatsingh]

Hey thanks,

The pipes are getting hot -- I haven't accessed the valve? Worth checking out?

[itchyfeet]

Most likely the valve but are pipes to heater and back both getting hot?
they are the smaller 20mm or so diameter pipes, best remove spare wheel to check by the valve

[syncronized]

Check the pipes aren't squashed where they are strapped to the chassis too, that problem stopped my heater working.

[bhagatsingh]

OK thanks -- I'll have a look to see if the pipes are jammed.

If not, is it worth just replacing the Heater valve?

Cheers

[itchyfeet]

As said check to see if they are hot either side first

[bhagatsingh]

OK will check in morning light and report back.

Am I right in thinking that w/out hot air blowing and full bleed, engine may overheat?

thanks for the advice much appreciated.

[CovKid]

No since you'd have to drive around with the heating on full in Summer if that were the case. You don't want air in the system though and you need to rev it higher than you think to force the air up through the bleed screw.

Bear in mind there are two rads - one for cooling, and one that does the heating. They run indepently although if your engine never gets up to temp, you won't get much hot air either.

[bhagatsingh]

I had the engine on for a good 20 mins this morning - gave it a good revvin -- went underneath and the small pipes attached to the switch mechanism were cold.

I'm in two minds -- I want to fix the thing before I embark on a 7-8 hour drive this evening, but if it's not essential (if it get air out of the cooling system without hot air blowing) then perhaps it'll be OK to fix at a later date?

Thanks again for all your help, much appreciated.

Tom

[CovKid]

Better fixed this time of year though. It won't be too long before the colder days creep in, at which point you'll have even less incentive to go crawling around underneath.