Heater Blowing Cold

[Mini_Lund]

I suppose this is a hot topic, but that's not the case in my mini!

I have ran the engine with the cap off and had it up to temperature, a few bubbles of air, but nothing major. Spoke to Rich, who suggested blowing through the heater hose - which was difficult at first but seemed to clear. However, all plumbed back in and its still blowing cold air. The hoses are getting hot as I am using my blank thermostat, heater valve open to allow flow once warm. Anything at the heater matrix end I should be looking at?

Thanks,

Tom

[checkmate91]

Two things spring to mind. First, air lock in the heater system. Resolved by taking the hot pipe off and filling it with water (don't hold it up too far otherwise you'll always be introducing air into the equation). Second, your thermo blanking plate isn't allowing the engine to get to temperature in this cold snap that we're having. I've had to blank openings on a-series cars in the past...

PS I sent you a PM a few weeks ago about your servo question. I'm happy to do a swap, just let me know if you're fixed ok or not...

[Cooperman]

Tom,

I don't know what sort of heater valve you have, but take the final end of the heater hose system off and run the engine slowly to see if coolant comes out. If it doesn't, there is some sort of blockage in the heater system. If that's the case, connect your garden hose to the heater hose and turn it on, Water should then flow out of the heater valve, having gone right through the engine and valve. That will isolate your problem.

Pete

[cone]

Have you tried putting a thermostat in ? running a blank will over cool the engine .

[Mini_Lund]

checkmate91 said:

Two things spring to mind. First, air lock in the heater system. Resolved by taking the hot pipe off and filling it with water (don't hold it up too far otherwise you'll always be introducing air into the equation). Second, your thermo blanking plate isn't allowing the engine to get to temperature in this cold snap that we're having. I've had to blank openings on a-series cars in the past...

PS I sent you a PM a few weeks ago about your servo question. I'm happy to do a swap, just let me know if you're fixed ok or not...

Hi Checkmate, I'm not sure I received an email from you? What is it you're wanting to swap? I have decided against using a servo now.

Thanks

Cooperman said:

Tom,

I don't know what sort of heater valve you have, but take the final end of the heater hose system off and run the engine slowly to see if coolant comes out. If it doesn't, there is some sort of blockage in the heater system. If that's the case, connect your garden hose to the heater hose and turn it on, Water should then flow out of the heater valve, having gone right through the engine and valve. That will isolate your problem.

Pete

Thanks Pete, I'll give this a go when the weathers only cold and not bloody freezing!

cone said:

Have you tried putting a thermostat in ? running a blank will over cool the engine .

Sorry, a bad choice of words on my behalf. I am using a thermostat, what I meant was it doesnt have 4 holes drilled into it!

Thanks

[guru_1071]

tom

if you have bleed and flushed the matrix out and its still blowing cold, you have to assume that the matrix is so clogged that it cannot give any heat out.

ive seen a heater recently that had no matrix in it, just a 'curl' of half inch copper water pipe conected between the rubber pipes - the owner was very puzzled as to why the output of the heater was so poor!

a new matrix gave him the 'full furnace' effect.........

[Mini_Lund]

Hi guys, I seem to have nearly sorted this issue now. I have got the majority of the air out the system, the heater is blowing hot air up until a particular point. When the engine is fully hot and has been hot for a while the heater blows cold?