Well i live in souther california and the weather recently has been hot, today it was about 94 degrees in the area where i live. I also live uphill and i have a black 840ci. i recently noticed the cars temperature guage going up past the halfway line if the engine is revd a little to much while im driving and also when i drive uphill, and the uphill drive to my house is pretty long. The mechanic i took it to a couple days ago fixed a fuse for one of teh ffans so the guage doesnt go up as much as it used to any more but im still curious. My question is whether its unusual still for the cars temperature guage to go up in this type of situation.

I would say it is unusual. It doesn't sound like your exerting too much stress on the engine, I've driven to Las Vegas in 5 hours from where I live which is 409 miles and about 40 miles of it is a very steep uphill. I have an 840 as well. I averaged 89.1 MPH during the whole trip and not once did my temp gauge go above a little less than half. I would suspect the radiator.

Don't let the engine get hot, you will kill it! The M60/M62 cannot handle overheating, you will warp the heads permanently (same story for the M30, M70, etc..).

If it's overheating like that, you need to take her in for a full diagnostic at a reputable shop. Fixing a fuse ain't gonna solve the problem for sure.

Cheers

Do the simple stuff first - check coolant level when engine is cold. If its low add some til it isnt. Check the level for a few days in a row to insure it is at the correct level. Do a fan clutch test. If clutch is defective replace it. As previously stated - dont mess with overheating - it can and will cost you an engine.

alright ill check out the coolant. i just drove it to the mechanic again for another quick check. everything went fine on my trip there, the AC was on. the mechanic told me to turn the AC off when i went up hill. on the trip back i checkd the temperature outside it was over a 100 and i noticed the guage went up a little, i turned the AC off and it went back to the halfway, when i drove up hill just now it stayed at the half way, i guess im just gna have to sacrifice the AC to keep myself cool in the car sometimes in order to keep the guage from going too high up. w/e one day when im done with school ill dedicate alot of time and money to this car and fix all these little problems up, i love my 8 series.

how about trying to bleed the cooling system?

The following assumes that your cooling system is properly filled and bled.

The temp gauge needle should be nailed one needle width shy of 12 o'clock at all times after warm up.

In your case, it's the Aux Fan, almost definitely.

When AC is on, the fan should engage. With engine off, remove the air tunnel top cover and check whether the fan spins freely. If there is mechanical interference, the magnets inside had become unglued. These can be reglued, saving the price of a new fan.

Next test - start engine with AC off. Have someone turn AC on while you watch the fan. It should engage.

The fan runs at two speeds as needed. Let engine run while someone monitors the temp gauge. If it does not switch speeds, the fan resistor is shot. It is attached to one of the spokes that the fan motor is attached to. Don't let temp gauge exceed noon - shut down immediately.

Let us know what you find and we'll go from there.

I am having a temp gauge issue as well. In my case, the needle quickly moves out of operating temperature toward red, stays awhile, and then moves back down to the middle VERY quickly. It only happens once per drive, and not again. I seriously doubt the coolant is actually that hot because in the morning, turning on the heater does not yield fully hot air until the car has been on the road for awhile (even while the temp needle is just below the red segment).

sounds like you need a new thermostat

I am having a temp gauge issue as well. In my case, the needle quickly moves out of operating temperature toward red, stays awhile, and then moves back down to the middle VERY quickly. It only happens once per drive, and not again. I seriously doubt the coolant is actually that hot because in the morning, turning on the heater does not yield fully hot air until the car has been on the road for awhile (even while the temp needle is just below the red segment).Bleed the system

Bleed the system



Fully agree - rapid needle movement is the result of an air bubble.

Hopefully you have not been driving like this too long.

how about trying to bleed the cooling system?


My 840 had to be Bled 3 times for proper cooling! I have been checking my fluide levels in the morning (dead cold) periodically!

I check all fluids,systems and tires before each "flight"! No room for mistakes.

My 840 had to be Bled 3 times for proper cooling! I have been checking my fluide levels in the morning (dead cold) periodically!


I remember, I was there....
How have you been ?

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here is the link http://www.youtube.com/watch?v=bKduku3UDkA

this is wat happens to my guage altho this is not my video, its a video of another 840ci, mine does the exact same thing on hot temperature days when im driving uphill.

It's still doing that? And you havnt taken her into the shop? If you keep lettin' her ride hot you're gonna kill your engine. A word of caution: BMW engines cannot run hot. If they do, they go to heaven.

...this is wat happens to my guage altho this is not my video, its a video of another 840ci, mine does the exact same thing on hot temperature days when im driving uphill.


WOW! You originally posted this problem 2 months ago and you still are cruising around with this problem. Have you read any of the responses to your original thread?
I would start looking around for a new motor, you are on the best path to needing one.

Seriously, start by bleeding the system (as mentioned) and check the coolant level when the car is stone cold. The red "bobber" in the expansion tank should be even with the top of the opening. If you still have this issue, take the car to someone who is knowledgable and can figure it out for you....

Also check for air blockage between ac condensor and radiator. I'd remove the radiator, clean the air restriction, might as well change the clutch fan and thermostat re-install with new coolant and bleed da F*** out of it. If its too late I have a M60 or M62(M70 and M73) if you cooked yours.

here is the link http://www.youtube.com/watch?v=bKduku3UDkA

this is wat happens to my guage altho this is not my video, its a video of another 840ci, mine does the exact same thing on hot temperature days when im driving uphill.


This same thing happened to me in my E36 before I blew the head gasket, thermostat housing, belts and radiator.

Check your water pump. That was the culprit of my problem. The water pump went bad, created loads of pressure in the cooling system and blew a huge hole in that plastic thermostat housing eventually blowing the head.

i know... i know... a 3 series doesn't compare to an 8er, but all BMW's of that era has this in common.

The following assumes that your cooling system is properly filled and bled.

The temp gauge needle should be nailed one needle width shy of 12 o'clock at all times after warm up.

In your case, it's the Aux Fan, almost definitely.

When AC is on, the fan should engage. With engine off, remove the air tunnel top cover and check whether the fan spins freely. If there is mechanical interference, the magnets inside had become unglued. These can be reglued, saving the price of a new fan.

Next test - start engine with AC off. Have someone turn AC on while you watch the fan. It should engage.

The fan runs at two speeds as needed. Let engine run while someone monitors the temp gauge. If it does not switch speeds, the fan resistor is shot. It is attached to one of the spokes that the fan motor is attached to. Don't let temp gauge exceed noon - shut down immediately.

Let us know what you find and we'll go from there.

Weird mine after it reaches normal operating temperature it sits half a tick over the 12 o'clock mark. Yesterday when I parked the car after a drive from work, it was pretty hot out. Came back out and got into it started it and the gauge was over half by two ticks.. I recently did the thermostat - could this be a waterpump?

im not gna lie, it got alot better after i took it to the mechanic, but not completely better, before in like 90 degree whether it would overheat big time like in the vid, after takin it to the mechanic he fixed the fuse for one of the fans and it only slightly goes up when i drive uphill in hot weather..but still i mean it bbothers me. but it doesnt ever go past 3/4 of teh guage like it did before and this rarely happens, again only when im driving uphill on hot days.

if it only does that only when driving uphill on hot days, drive with the heater on, it will get all of the hot air out of the engine compartment and cool down the operating temp of the engine.

worked for my M62 when i know she's going to have a hard day! it ran about 3 or 4 ticks cooler!

It should never go more than one little tick past the middle of the gauge. 3/4 past is not good at all, at any time.

Cheers

if it only does that only when driving uphill on hot days, drive with the heater on, it will get all of the hot air out of the engine compartment and cool down the operating temp of the engine.

worked for my M62 when i know she's going to have a hard day! it ran about 3 or 4 ticks cooler!
wow rlly? never knew that, ill try it next time.

wow rlly? never knew that, ill try it next time.

that may be a quick solution, but you need to find the cause and fix it correctly, not just get out a Band-Aid and hope things work out well...

that may be a quick solution, but you need to find the cause and fix it correctly, not just get out a Band-Aid and hope things work out well...
hey, i tried it and it worked, but ur right, next time i visit the mechanic ill let him kno and see wat he says.

my M70 did get a little hot when driving up hill before, an if I drove with high rpm for a while.
(this was just after I bought it)

I changed the thermostat, got better, but not good. The high rev issue cleared, but could get a slight increase in temperature up very long hills, i.e mountain passes.

Then last summer my radiator busted. cracked at the top.

After I had it replaced it's been fine, no overheating at all.

So if you are running a 15+ year old radiator, you might have a flow issue.

Also like Wuffer suggest, the fan clutch, I'm replacing mine this week.

Whenever my car overheated I too turned my heater on max to increase ciculation in the coolant system, that usually cooled it down in seconds.
This is because you open up the heat exchanger loop in the engine, and cool down the water with the air that flows through heat exchanger and heats up the drivers compartment.

hey, i tried it and it worked, but ur right, next time i visit the mechanic ill let him kno and see wat he says.


means 1 of 2 things...

either the cooling fan doesn't engage when supposed to or your water pump is starting to go!

send an email to bimmerzone.com, i don't remember exactly what the quoted me for a cooling system setup but i know it was a kick ass price!