Heater air lock

[Jon280]

Well all the cooling pipes apart from one awkward hose have been replaces, and when run up to temperature there were only a couple of dribbles that were soon sorted.

However, there appears to be an air lock in the heater system, as not getting any hot air, and the return pipe remains cool. Any tips to sorting this, or will it sort itself if given a bit longer to run when up to temp and fully pressurised?

Also, the fan is not kicking in, though that might be an idiot mistake, as I don't actually remember plugging the fan in.... Will take a look when I get back out to the garage at some point, and hopefully find an unmated connector!

[gog440]

Only the standard advice, heater to max heat then run the engine with the top off the tank.any air should bubble through.

[mrzigazaga]

gog440 said:

Only the standard advice, heater to max heat then run the engine with the top off the tank.any air should bubble through.

As well as this did you fill it on level ground?..Squeeze the bigger hoses when its warming up a few times..Almost like you are pumping them..When it has cooled down a bit top up the levels to max from the swan neck and then the expansion tank..Squeeze the hoses again..Warm it up to see what temp it gets too..You did put the Thermostat in the right way round?....Ziga

[Jon280]

Yeah, thermostat is the right way round, and that bit is all working as it should. As I had it running the inlet pipe to the heater did seem to be getting warmer, but then I ran out of time. Hopefully will get the chance to have a tinker again tomorrow and running it a little longer will get the air out!

[Jon280]

Let it run for a bit longer and gave the pipes a bit of a squeeze and after a bit there was a nice gurgle and then hot air from the heater.

Also discovered that fans work better when they are plugged in!

Now just need to put the lights, indicators, bonnet, dash, speedo cable, front spoiler and numberplate all back on..

[jmorgan]

Not sure what your pipe arrangements are like but on the 400 there is quite a high point in the heater go/return through the bulkhead. I fitted a bleed valve to aid filling and getting rid of airlocks in the return.