Bleeding

[Scottd]

I unwisely fitted my new heater matrix without refilling it with coolant first. The fact that no hot air came from the blowers alerted me to one almighty air block, temp gauge was fine, radiator was hot but matrix and pipes around it were cold. So undid the jubilee clips around the matrix, bled what I could, then topped up coolant and now all seems fine (after a 20 min drive). Temp fine (maybe fractionally more fluctuation than I'm used to but might be me being paranoid/watching it consantly), all pipes an matrix hot + hot air from blowers.

Not a particularly scientific fix I know, I'm assuming there could still be small air blocks in the system. Will they work their way out? Is it something I can live with for a bit? I'm probably going to be visiting Ali in a few weeks so can I drive about till then an get it bled properly by him? Or even (heh) DIY if it's something I should get done urgently!?

I hear issues like this related to HGF and having gone thro that just 8 months ago am in no rush to go thro it again

cheers!


Scott

[Rich H]

As I understand it the matrix isn't usually bled as its so low in the system. It'll sort itself out in a while.

Just bleed it in a few days.

Rich

[robin]

The most important thing is that the whole rad is hot.

You can usually diagnose any flow (or lack or flow) problems best by running the car on the idle from cold and watching the temperature gauge.

It should start of cold enough to have no indicated temp on dash.

Run the engine on the idle and the temp will climb to your stat opening temperature, at which point it will level out.

Now on an S1 on a cold day the temp will probably stay there indefinitely as the flow through the rad is high enough to keep the engine cold.

However, if you're in a garage you might find that the temp eventually continues to climb to the fan cut in point.

It is vital that the temperature stays constant at the stat temperature for a good few minutes while the radiator gradually heats up.

An air lock in the heater matrix will change the behaviour of the bypass a bit, but not dramatically.

Air bubbles in the matrix should end up in the expansion tank eventually (or they'll stay stuck in the matrix for ever).

If the only air in the system is in the matrix and the void at the top of the header tank then you're not adding to the HGF risk.

Cheers,
Robin

[Scottd]

Cheers