Morris Minor Owners Club

Any tips on removing air lock from heater would be gratefully received, the system was filled from scratch and the heater was dry. Symptoms-----cold air.

Remove heater pipes from bulkhead and fill heater from there. Then when the rest of the system is full run with the rad cap off. You can also bleed air from the heater control valve by loosening the connection to the head.....

Thanks, done as you suggested, but kept the cap on! Makes sense to let the air out!

Keep squeezing the hoses as well as this can help to work the bubbles out the system....

i bled my system by filling the entire system through the hose going from the block to the heater, i took it off the block and put the water in the hose. it went through the heater down into the radiator, through the radiator and into the block and then filled the block and leaked out the heater fitting on the block. then it was a case of very very quickly lower the hose down onto the fitting. seemed to work alright, i havnt had problems.

morrisman1 wrote:i bled my system by filling the entire system through the hose going from the block to the heater, i took it off the block and put the water in the hose. it went through the heater down into the radiator, through the radiator and into the block and then filled the block and leaked out the heater fitting on the block. then it was a case of very very quickly lower the hose down onto the fitting. seemed to work alright, i havnt had problems.

I have done exactly the same when filling the system from 'dry'. Mind you, I did check that the heater matrix was not blocked first! I would try the above first and if no result then check the heater matrix by connecting a garden hose to one pipe and see what comes out of the other (if anything). Also, your heater tap on the back of the engine might be faulty/blocked.

very timely thread, I'm about to do mine, thanks everyone

A similar method as already mentioned is with the engine running just take of one of the heater pipes and reconnect as soon as water appears which is normally straight away this normally burps the system.

Extreme but it works. Radiator bleed valve. Charlie.<br><br>

When you have carried out those instructions take the car for a run. The extra speed of the water pump should push any remaining air out of the system

When you have carried out those instructions take the car for a run. The extra speed of the water pump should push any remaining air out of the system

I've always done this to bleed the heater - the water pump at speed should provide enough flow to flush air out fo the heater. beware though if the heater is totally empty as all that air will end up 'somewhere' in the cooling system.

If in doubt, fill the heater with the garden hose on one pipe - the excess water comes out the open pipe connection.

I've never in all my years known the heater system not to self bleed. Really should be no need for any back-filling or bleeding - provided the hoses aren't kinked and the heater valve is open of course!

Like Kevin says, but it has to be the heater outlet hose you take off. I take the heater hose off the top end of the bent copper pipe, open the heater control valve, start the engine, rev it until coolant starts to spurt out of the hose, then stick the hose back onto the pipe. A bit messy but it definitely works. You'll have to top the radiator up afterwards.

*scribbles notes*

Seriously - just fill it up to the brim and rev the engine - that's all you need to do!

i've never seemed to have had any trouble bleeding the system either, i figure it's not a fussy cooling circuit like some modern cars and the bypass hose from the rad allows anything to burp out. running fluid through the heater is a good idea tho.

You're nearly 3 years too late!!!!!!!

I have no problems getting rid of my trapped wind

i get told off if i do that!

as for the 3 years gap between posting, it's been a long time, i just had to find the right words!