Dead heaters

Post by **magnumpi** » 20 Feb 2008 01:20 am

I think i jinx myself sometimes.

It was less than a week ago that i was singing the praises of how good my heaters are, and imo they are one of the best bits of the car and so on......
Leaving my GF's the other night, freezing cold, heaters on, then without me touching anything heaters off

Checked the fuses, they are all fine, so anyone know what it could be?
common fault?
easily rectified?

Many thanks

Post by **SteveP** » 20 Feb 2008 10:26 am

I assume the fan doesn't work in any of the heater positions? If that's the case then it's likely to be the resistor pack in the heater box inside the engine bay - common fault

Post by **classicswede** » 20 Feb 2008 01:55 pm

Or worse still the heater fan motor could have burnt out. I've only ever seen that once so a rare problem.

Post by **Batteries included** » 20 Feb 2008 08:21 pm

Try feeling the temperature of the hoses where they disappear through the bulkhead to the inside the car from the engine compartment. The ram effect of the air as the car moves forward should introduce warm air into the car even if the fan is not working. If the hoses are not warm, then maybe no coolant at all (hopefully not the problem!!) or maybe the heater valve is blocked or stuck closed.

Might be a failed thermostat which means that at this time of the year the coolant never gets properly up to temperature, though you ought to get some warmth even if that's the case. Feel the top and bottom radiator hoses with the engine warm - keep your fingers clear of the fan!

In my 1980 343 I found that the lack of heat was due to the bottom port on the water pump being blocked by crud preventing water from flowing back from the heater - the car lived for most of its life in S Africa where the heater was never needed, but that's not the case in the UK right now! I started the diagnosis by using a hosepipe at low cold water pressure to see if water was flowing through the heater's heat exchanger. Don't use the full cold water pressure otherwise you'll rupture the heat exchanger which produces wet feet!

I'm sure your problem is easily fixed.

Good luck with it!

Alex

Post by **magnumpi** » 22 Feb 2008 12:59 am

They did work absolutely fine, up until the evening of the problems.

No, they don't work with the heater switch in any position.

I'll go down the resistor route first, coz it's probably easiest/cheapest and see how i get on.

Cheers for the tips guys