Heater temperature

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Theantony
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Heater temperature

Post by Theantony »

Hi. I had a new water pump put in but now the heating is cold even on full and the temp gauge is Barely a quarter way up to centre. Is this a thermostat Issue or do I need to bleed the water.

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Re: Heater temperature

Post by matthewdesigns »

Might as well try bleeding since it is far less involved than swapping the thermostat. If you've personally never bled the system, there's a screw on top of the thermostat housing that make this a relatively painless process.

However it's likely the t-stat. I recently resolved the same issue by replacing that part (and then of course bleeding the system again). Be aware that there are at least two types of thermostat housings, and associated 'stats, for the M30. In addition, I had an oddball housing on mine that used the early part number as well.
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Theantony
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Re: Heater temperature

Post by Theantony »

Ok will do. Ive never bled a system any pointers please.
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Theantony
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Re: Heater temperature

Post by Theantony »

Just ordered a new thermostat.
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Re: Heater temperature

Post by Pod »

Theantony wrote: Tue Jan 29, 2019 4:11 pm Ok will do. Ive never bled a system any pointers please.
IF the 8mm screw is not immovably rusted into the 'stat housing, you just need to undo it a little until air stops escaping. If the screw won't move, try working it to-and-fro with a pair of mole grips, as the hexagonal head will no doubt already be rounded off! Try it with a warm engine and some penetrating fluid.

You MAY get an airlock in the heater matrix.
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Re: Heater temperature

Post by bpoliakoff »

Of interest and to flesh out what Pod just said, sometimes when a bolt or nut is frozen you can break it lose by trying to tighten it first. Diesel fuel, which is basically kerosene, IIRC, is a good frozen bolt breaker as well as a good parts cleaner, as stinky as it is.
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Theantony
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Re: Heater temperature

Post by Theantony »

Thanks for replies. Yes tighten too Posen is the way. The breeder nut is fine, I bled it yesterday and no joy so Im going to change the thermostat.
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