Temperature never goes halfway>> Suggestions please

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N4SBM
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Post Fri Feb 17, 2006 11:07 am

The temperature gauge on my 89 320i cab never goes halfway even when driving for an hour, its not the actual gauge cos it does go to halfway after LONG time (only seen it once), What can it be??

Suggestions Please...

#Thanks#
jmc330i
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Post Fri Feb 17, 2006 11:17 am

The temp guage on my 325i never got to halfway unless it was stuck in traffic on a hot day.
James
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N4SBM
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Post Fri Feb 17, 2006 11:25 am

N4SBM wrote:The temperature gauge on my 89 320i cab never goes halfway even when driving for an hour, its not the actual gauge cos it does go to halfway after LONG time (only seen it once), What can it be??

Suggestions Please...

#Thanks#
Also cuts out when on low gear and engine is hot, also cuts out once i just switched it off from driving a while, could it be throttle??
e30_Turbo
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Post Fri Feb 17, 2006 11:37 am

I'd check both sensors in the thermostat housing as they both corrode quite quickly. They should be bronze! Also check the thermostat is opening too, mine was stuck open and had the same effects until it stuck shut and it overheated.

HTH, Mark.
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Simon
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Post Fri Feb 17, 2006 11:48 am

Sounds like you're cooling system is running very well....unless you're stuck in traffic constantly, then it should head for the halfway. Where I live, there's lots of mountain roads, and when driving down a mountain pass, which are about 3-4miles long, the guage often heads for the blue in this cold weather.

On motorway this time of year, I'd expect the guage to be between the quater and halfway marks.
Last edited by Simon on Fri Feb 17, 2006 11:50 am, edited 1 time in total.
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dobbie82
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Post Fri Feb 17, 2006 11:49 am

our 320i touring only goes up to just over quarter.... mark has even done 1000 miles in a day and still it only went that high.
Dan318-is
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Post Fri Feb 17, 2006 1:09 pm

sounds like a thermostat to me
Gouki
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Post Fri Feb 17, 2006 5:19 pm

mine stays at a quarter or thereabouts, only if stuck in long traffic does it go just below half way.
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N4SBM
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Post Mon Feb 20, 2006 12:46 pm

Thanks for all the suggestions guys, most appreciated..

It seems that all of the suggestions are very common on most e30's.. Now i have peace of mind...


Thanks
mrLEE30
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Post Mon Feb 20, 2006 3:34 pm

i thought that if your thermostat was working correctly and is the right part, your gauge should always read in or very near to the middle, irregardless of how hot or cold it is and where you are driving.

a cold thermometer reading would mean a cool engine which would mean your fuel would be rich and engine power/fuel consumption would be bad, not to mention the chance of bore washing. This would happen if the thermostat was wrong or mis-operatring.

As for sat in traffic i live in Bahrain where summer temps are in excess of 45-50C, my 325 runs in the middle so long as the fan clutch is in good nick and the coolant is of the right quality/mixture, and the radiator flushed before each summer. it matters not if i am driving or sat in traffic.

please correct me if i am wildly wrong 8O

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tonyppe
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Post Mon Feb 20, 2006 3:47 pm

mine sits a needle with below the halfway line. ALL THE TIME, except the odd occasion where if im in traffic it will go to dead on the half way, then return back once the thermostat has fully opened.
another thing it sometimes does if im in traffic for a really long time and the needle has gone back to just below the half way, and i drive off, cos the thermostat must be fully open, the rad cools a lot of water and cools the engine to in between the quarter and half way. but because of this the thermostat starts to close and bring the temp up to just below half way again. :)

its always going to move as the moving parts change etc etc.
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tonyppe
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Post Mon Feb 20, 2006 3:50 pm

just remembered, 325s have ally heads, not sure about 320's or others.

the engine getting too hot can make the head crack, as ive seen a couple of times. :x
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Post Mon Feb 20, 2006 7:02 pm

mrLEE30 wrote:i thought that if your thermostat was working correctly and is the right part, your gauge should always read in or very near to the middle, irregardless of how hot or cold it is and where you are driving.

a cold thermometer reading would mean a cool engine which would mean your fuel would be rich and engine power/fuel consumption would be bad, not to mention the chance of bore washing. This would happen if the thermostat was wrong or mis-operatring.

As for sat in traffic i live in Bahrain where summer temps are in excess of 45-50C, my 325 runs in the middle so long as the fan clutch is in good nick and the coolant is of the right quality/mixture, and the radiator flushed before each summer. it matters not if i am driving or sat in traffic.

please correct me if i am wildly wrong 8O

mrlee
Not sure about cars sent over your way, but over here, when the temp guage is halfway, this is when the viscous is engaged to turn at engine speed.
All my E30's have run between quater and halfway after a good cooling system overhaul, halfway when in traffic, and just over quater mark when on the motorway etc, as I said above, in the winter, on a drop down a local moutain pass, I've seen the guage go past the quater mark towards the blue! In my opinion, this is a evidence of an efficient cooling system

Last time I saw my car running at halfway on a motorway run, bear in mind it wasn't summer time, was when I had a cracked cylinder head.
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Richy325iTouring
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Post Mon Feb 20, 2006 10:40 pm

spot on si
the se runs halfway all the time unless parked with engine running then it runs just under half
my touring ran just under half untill i warped the ehad the bugger went mad

anywhere between quarter and half is fine if its at a quarter then your cooling system is working effctivly so noting to worry about
just panic when it gets over half
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Brianmoooore
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Post Mon Feb 20, 2006 11:05 pm

Should be as MrLEE says. Once the car has warmed up the needle shouldn't really move at all.
Any dropping of the needle when under light load is diue to the thermostat leaking slightly when closed, or possibly the heater full on.
Any rise in temp when under load indicates a heat transfer problem somewhere, probably a scaled up or partly blocked radiator, and any increase in temp when stopped is due to a faulty viscous fan coupling.
None of this is a problem as long as the needle stays well away from the blue and the red. The gauge is not linear, and the centre section only covers a few degrees.
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Post Tue Feb 21, 2006 7:46 am

thanks brian,

had this arguement with a BM salesman when looking at a freinds 330cab (e46) he was going to buy. told him the guage indicating cold is a problem, so it went to service before my mate purchased it, and when back sure enought bang in the middle, my Z3 same and E30 sport, only my 320 cab runs cool but i am sure that is due to faulty thermostat, which i will change along with blue temp sensor when back form my hols.

mrlee (not Mr LEE !!!)
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Post Tue Feb 21, 2006 6:12 pm

I wouldn't be happy with my car running at halfway on a motorway at this time of year, and so far none have!
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Post Tue Feb 21, 2006 8:43 pm

Was going to say, MrLee is right!

My mate bought a brand new E36 a few years back now, I had an E30 with the temp 1/4 always. Went for a drive in his car, I came back and said......."its fooked"
I explained to him the temp sits bang in the middle, which he replied was correct and my car was wrong! Doh :?

Temp should sit bang on in the middle!
telski789
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Post Tue Feb 21, 2006 8:52 pm

mine sat dead in the middle of the quarter to half,then i changed the rad and the thermostat and now its always in the middle,weird!

Tel
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Post Tue Feb 21, 2006 8:59 pm

The temp guage shouldn't sit in the middle...officially, anywhere inside the 2 coloured zones is normal operating temperature. It depends on what time of year it is, and also where in the world you are, and what sort of driving you are doing at the time.

The viscous engages when the temp guage is halfway, so can't see how driving around with the viscous engaged constantly is normal?

As I've said previously, I've not had one e30 that sits halfway constantly, only when in traffic.
My touring did when I first bough it, but I soon serviced it, and the coolant was a watery brown colour, original thermostat, original water pump, original viscous, block was full of crap, rad was full of crap, after that, it ran at between quater and half, and still does, which I'm happy with, if it was running under quater near the blue, then I wouldn't be happy with that.
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Post Wed Feb 22, 2006 12:55 pm

WIth the M20 engine, as far as I know, the temp guage consistently showing over halfway is a problem. It shoudl stay below halfway, only being halfway when in traffic in hot weather.

My 320i was caned round 4 consecutive laps of the Nurburgring, and did 7 20min sessions of Cadwell Park in a day and never has the temp. gone over halfway.
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Post Wed Feb 22, 2006 1:40 pm

if its a worry, do what the army does..

But a flap or cardboard between the grill and radiator.. only block 1/4 - 1/2 then drive.. you'll wamr up even quicker!

I think the army use canvas, that way there is still airflow, but just restricted