Thermostat Question

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brandonturner
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My E21(s): 77 BMW 320i

Thermostat Question

Post by brandonturner »

Hi Guys,

I have a 77 BMW 320i that I just installed aftermaket gauges for coolant temp. I have a 80 deg thermostat currently in the car. The temp runs between 190 deg- 210 deg, is this to high for these engines? Should I run a 75 or 70 degree thermostat?

Thanks


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Peter V.
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Re: Thermostat Question

Post by Peter V. »

I presume you mean degrees Celsius and degrees Fahrenheit?

You're aftermarket gauge is in deg. F?
Gr Peter V.

.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.

BMW E21, 1981 320/6 Ascot Grau.
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Jeroen
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Re: Thermostat Question

Post by Jeroen »

That happens when you're born on Celsius land haha

190-210F is abt 88-99 degrees
stock thermostat is 80 degrees indeed which makes your readings on the high side indeed

but there could be many causes to a car running hot, also see our FAQ on cooling

do you have an electrical or mechanical fan, or both?
Regards/groeten, Jeroen
brandonturner
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Posts: 7
Joined: Sun Jun 16, 2013 7:48 pm
My E21(s): 77 BMW 320i

Re: Thermostat Question

Post by brandonturner »

Sorry guys, my reading is Fahrenheit. I have a mechanical fan, & electrical fan. I had 83 E21 that ran at the 3/4 mark on the stock temp gauge so I changed to a 75 degree thermostat and that worked goo. Im not sure if this is considered running hot, because my stock gauge doesnt work. It is a steady temp and never goes about 210 f, until I turn the car off, but I want to make sure this isnt to hard on the engine.

Thanks
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Jeroen
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Re: Thermostat Question

Post by Jeroen »

Well I believe normal operating temp is supposed to be around 88 degrees, around 91 degrees the first stage of the fan should kick in to blow extra air and at 99 degrees stage 2, temp should never exceed 99 or 210F but for a longer period that can be harmful already.

If the electrical fan works you have all means of cooling operational. What's the outside temp on average? Only on a hot day and in traffic 210F is acceptable to me. In other situations the water pump may be work or the radiator clogged. When did this problem start? Enough flow, thermostat opening up, no air left in system, ignition timing checked?
Regards/groeten, Jeroen
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