Today I noticed the engine temp rising a bit. [Solved]

[titodj]

A couple of weeks ago I started getting the coolant level low warning, It would come up randomly and just for a couple of seconds.
I still need to figure out why, and I'm going to check the sensor connection as suggested.
(The coolant level is fine)

But I hadn't have any problem with the engine temperature before.
The needle was either all the way to the left when cold, and at 12 o'clock when at running temp, and never went higher even with the summer temps here in Las Vegas, but today I noticed that when I was stopped during a red light, the temperature went up, not all the way, but a little before the "red zone"

Then when I started driving went back down again, The fan in front of the radiator is fairly new, and I'm pretty sure that I've heard that is working a couple of times this week when I got home and turned off the engine.
I didn't heard it running today, so I guess that is a possibility, but assuming the fan is right, what else could be causing that change in temperature?

Thanks !!

It was both, the level sensor (that was old)
And the thermostat that was new and failed in less than 3 months
I replaced them, and all seems back to normal !

[andrewwynn]

The temperature indicator on the dash is not a gauge it's a 3-step idiot light.

It's designed to snap to 12:00 for about a 30°C range of temperature. It will erroneously indicate proper temp over a very wide range of not good temp.

If it ever goes past noon it's already overheating. You said the coolant was low ? Resolve why. (Usually a leak in a hose fitting or the overflow reservoir).

Use the hidden menu to monitor actual ect (engine core temp) or coolant temp I can't remember which is accessible from that menu but you'll see how relatively worthless the non-gauge is on the dash.

[cn90]

- What is your mileage? Mileage is always important i any new post seeking help.

- I did the partial cooling overhaul at 113K. I am now at 130K and still rock solid.

- Here is the DIY:

https://xoutpost.com/bmw-sav-forums/...16k-miles.html

[titodj]

Originally Posted by andrewwynn

If it ever goes past noon it's already overheating. You said the coolant was low ? Resolve why. (Usually a leak in a hose fitting or the overflow reservoir).

Use the hidden menu to monitor actual ect (engine core temp) or coolant temp I can't remember which is accessible from that menu but you'll see how relatively worthless the non-gauge is on the dash.

No, the level of the coolant level is fine, the expansion tank, the water pump that thermostat and the hoses are new.
everything was replaced a couple of months ago, and no leaks or coolant level dropping.

I have to drive to Pahrump tomorrow I will use the hidden menu to monitor the temperature, it's about 100 miles round trip.
But is highway, so I don't know if the temperature will rise.

[titodj]

Quick update, I just figured out that the fan clutch is FUBAR, I noticed that was almost freewheeling with the engine off and just pushing it with my hand, then I started the engine and use some paper and it stop.

So I ordered a replacement, that should be here Sunday.

2 questions:

1- I guess this could be the culprit of my problem right?

2- it it risky to drive 100 miles with the fan clutch not working? (freeway)

[andrewwynn]

The fan's job is to push air of the car isn't moving. It doesn't do much at highway speed if anything.

Monitor temp and you will be fine also the electric fan should kick in if the tempo gets hot enough.

The clutch is meant to be pretty free I'm able to stop my fan with cardboard when the engine is running.

When my thermostat was broken open I blocked my fan so I could have heat inside. I only used a piece of foam.

Did you say you replaced the thermostat? Stuck closed tstat will give you over heat.

[titodj]

Originally Posted by andrewwynn

Did you say you replaced the thermostat? Stuck closed tstat will give you over heat.

Thank you, I'll be checking the temperature.

Yes I replaced the thermostat, a couple of months ago, but I guess failure is possible too.

As for the clutch, I hope that's the culprit, I will replace it, and report Monday if the problem was fixed.

[FRod1981]

The only way to potentially avoid overheating is to overhaul the cooling system every 125k/mi or so. But doesn't prevent new part failure, sadly. Hope you figure it out before something bad happens. Are you sure you dont have a bubble in the system?

[Fifty150hs]

If it's running cool it's usually due to a thermostat that's stuck open. That's better than stuck closed. It just screws your fuel mileage.

[titodj]

Originally Posted by andrewwynn

Did you say you replaced the thermostat? Stuck closed tstat will give you over heat.

So I replaced the clutch, but as soon as I started the replacement, I figured that the clutch was not the problem.
When I removed the plastic covers, i noticed leak stains on the expansion tank, so the tank obviously failed even though is basically new (3 months).
I'm ordering a new tank, but I have a question, is there a way to check the thermostat?
Is new too, but I don't want to drain the system to replace the tank, and then figure I need a new thermostat too.

Another question, when replacing the tank, should I order the transmission thermostat too?
Its also 3 months old.

Thanks !!