Fisrt Sign of Snow and Bloody '82 1.3 heater problems!

Good Evening,

Hopefully someone can help, now the weather is rapidly dropping cooler I'm realising a reliable heater would be very useful. Basically, on the odd occasion my heater works, and works well, all speeds, blows hot when  slid to hot and cold when slid in the opposite direction. However, my heater only seems to work when I'm doing motorway driving (at high revs), once I'm back on normal roads, and my revs drop the heater seems to stop working. I must add, my heater sometimes works on high revs, but not all the time. More often than not it doesn't!

At the moment I'm having to struggling by with the small amount of hot air that very gently trickles through when heater is off, so any 'heat' that can be thrown on this situation would be greatly appreciated.

Thanks

drain, flush, filll and bleed the coolant, and stick a new thermostat in there while you're at it.

if you can be bothered to pull the dash out then you can check that all of the ducting and pipework that directs hot air to the vents in the dash are connected up, and not blocked with leaves or other crap.

or just wear a thicker jumper ; )

Check belt tension , also check return flow into expansion bottle, maybe weak water pump

With Big_Nick on this one
Flush the system out and back flow the heater matrix pipes with the hose pipe, that way any crude thats built up is more likley to flush out. Its suprising sometimes what comes out!

It's because the airflow over the car at motorway speeds pushes more air through the heater into the cabin.  When you're back to town driving there's no pressure to do that.

The heater is obviously straining now so needs more electric drive than it should. Thats why it blows more as your engine revs higher.  the faster speed of the alternator is feeding the heater the extra power.  

Is the heater noisy?


I just replaced my heater box because the one in my cabby was growling like hell and eventually packed in altogether.  Luckily I had another heater from another mk1 to put in.

Fortunately if you had to replace yours, its much easier in a tintop because there's no kneebar to remove