Evening all,
Sorting a list of jobs out for the winter and want to change the thermostat what’s the coolest running temp thermostat I can get for my 323i and am I better off using genuine BMW parts ?
Thanks in anticipation as always,
Cheers Tim.
Thermostat help for my 323i
Moderator: martauto
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Foe
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Try Cotswold on here. Jon knows his stuff and will get the correct part for your car.
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Tim64
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Cheers mate will do
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Brianmoooore
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First of all, why do you want to run a lower temp. 'stat than the one BMW specified? The ideal running temp. for an internal combustion engine is as hot as possible without local boiling occurring in the head, which for the 323i is a lowly 80 degrees.
I've never been a fan of genuine BMW thermostats. They have a design fault which results in the bridge piece that holds the capsule breaking on one side, stopping them fully closing. It's possible that the design has now been improved for replacements, but the problem with OE 'stats continued right up to the last models to use a conventional one.
I've never been a fan of genuine BMW thermostats. They have a design fault which results in the bridge piece that holds the capsule breaking on one side, stopping them fully closing. It's possible that the design has now been improved for replacements, but the problem with OE 'stats continued right up to the last models to use a conventional one.
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Tim64
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Thanks Brian,
If not a genuine stat have you got a type you prefer ?
And thanks for your explanation on running temp I thought running cooler would be better for it,
Cheers Tim.
If not a genuine stat have you got a type you prefer ?
And thanks for your explanation on running temp I thought running cooler would be better for it,
Cheers Tim.
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boiliebasher
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Tim, the OEM thermostats I have bought/ removed from my E30's have been made by BEHR and Wahler.
Hope this helps
Hope this helps
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boiliebasher
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Oh an original 80°C as Brian mentioned is completely adequate and no need to drop below this temp what so ever imho.
Just to put it in perspective, my 540i V8 comes fitted with a 95°C thermostat as standard !!
Personally never had any issues with BMW OEM thermostats. However as I mentioned if go with BEHR/Hella or Wahler you should be fine.
All the best mate
Just to put it in perspective, my 540i V8 comes fitted with a 95°C thermostat as standard !!
Personally never had any issues with BMW OEM thermostats. However as I mentioned if go with BEHR/Hella or Wahler you should be fine.
All the best mate
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paultv
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On a side note, I'd be interested to know what the gauge range is between a quarter, half and three quarters? So when your temp rises from quarter to a half how many degrees are we looking at?
I've not been able to find anything specific about this - I imagine Brian might well have an idea.
Paul
I've not been able to find anything specific about this - I imagine Brian might well have an idea.
Paul
4th May 1990 325i Convertible.
BMW E30 Cabriolet Best Mod Ever:
https://bmwe30cabriolet-wdm.blogspot.com/
BMW E30 Cabriolet Best Mod Ever:
https://bmwe30cabriolet-wdm.blogspot.com/
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Brianmoooore
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A M20 has a 80 degree 'stat and a M40 a 88 degree one. The former runs with the gauge just about on the quarter line while the needle in the latter is on the centre line, so we can infer that difference on the scale is about 8 degrees. Don't US spec. gauges have numbers on them?
As cylinder head design has evolved, eliminating local hotspots, and as materials have improved, enabling cooling systems to run at higher pressures (we won't mention BMW black plastic), the running temp of engines has increased, as boiliebasher's 540i illustrates.
As cylinder head design has evolved, eliminating local hotspots, and as materials have improved, enabling cooling systems to run at higher pressures (we won't mention BMW black plastic), the running temp of engines has increased, as boiliebasher's 540i illustrates.
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BenHar
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I thought the M20 used an 82 degree stat?
Ben
Ben
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Brianmoooore
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80 according to ETK, with no options shown.
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Tim64
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As always thanks so much for everybody’s help really appreciate it,
Cheers Tim.
Cheers Tim.
