temperature rising and it's freezing out there ...

[Braincrank]

Just came down the M1 and there was some traffic were the speed was about 30 mph and suddenly the temperature went up .... Once the traffic eased and I was back to cruising speed the temperature leveled out at just just over 80 which is normal for my car.
My guess is thermostat ?!
Also, the warm air outlets in the car blow hot and suddenly go cold. When I switch the heating off and after a few minutes on again it blows hot for a while and then cold on pax side but driver's side is lukewarm to warm ....
Any suggestions what else it could be are much appreciated !!

 

[Braincrank]

The heating issue is probably the duo valve ?? Or is there another switch that could have a gremlin ?

 

[Braincrank]

Could it be the little pump that sits between the water pump and duo valve ?

 

[Auto-mobile]

I'd be looking wat thermostat first, easy job and cheap enough in your car, duo valv won't effect engine temp only heating in the cabin.

 

[Braincrank]

Right, so I fitted a new thermostat and now the engine temperature only stays a hair width below 80° . Can't remember the engine ever running at that temperature. It's normally at the next line above 80° .
Did they flog me the wrong thermostat? Is it bad to run the engine a bit cooler?

 

[Braincrank]

I wouldn't have thought that the duo valve is messing about since I only put a secondhand one (in good condition) in not long ago. So now I think it might be the little pump that sits between the water pump and duo valve. It's still the original one so it's done 27 years ....
Does anyone know if it's easy to take apart and clean or should I rather try and locate another one ?

 

[AMGeed]

Should be running at around 87c

Did you get the thermostat from the dealer or is it aftermarket?

 

[Braincrank]

GSF-car parts
Two blokes double checked the ref no.
But then two can be double wrong ...

 

[Braincrank]

Is it correct that the engine uses more fuel when running cool ?

 

[moonloops]

Is it correct that the engine uses more fuel when running cool ?

Yep

 

[WDB124066]

Just came down the M1 and there was some traffic were the speed was about 30 mph and suddenly the temperature went up .... Once the traffic eased and I was back to cruising speed the temperature leveled out at just just over 80 which is normal for my car.
My guess is thermostat ?!
Also, the warm air outlets in the car blow hot and suddenly go cold. When I switch the heating off and after a few minutes on again it blows hot for a while and then cold on pax side but driver's side is lukewarm to warm ....
Any suggestions what else it could be are much appreciated !!

Is this a W124...?

 

[Braincrank]

Yes.

 

[WDB124066]

I had a thread on here a little while back on overheating, maybe read through that and see if it raises anything relevant for your situation...

http://www.mbclub.co.uk/forums/engine/211568-largest-124-radiator-6.html#post2401838

 

[Auto-mobile]

Not just running cooler because the heater is on and it's colder outside?

 

[Braincrank]

That's what I'm thinking at the mo.
It's not quite the right environment to test it when it's freezing outside ....

 

[Braincrank]

Not the best quality pic but that's how it normally is .



That's how it was this earlier after a 5mile stop start city drive , must add that the missus had the blower on to keep the windscreen clear .

 

[Braincrank]

Pics are the wrong way round ....
The warmer temp is how it's used to be and the cooler one was from today ...

 

[ray_hennig]

Pics are the wrong way round ....
The warmer temp is how it's used to be and the cooler one was from today ...

I would want my W124 to run at the higher of your 2 temperatures. Just under 90 C.

RayH

 

[Braincrank]

Yes, that's at which it always ran until I came down the M1 on 29.Dec and while in traffic doing 30mph the temperature went up although it the outside temperature was only round 5°C or thereabouts.
Most peculiar ....
The part number of the thermostat I got from GSF is 176ME001 and it states on the receipt it should be 87°C
Maybe it is the cold weather that's mucking about with the reading but I thought the thermostats job is to keep the temperature at a steady level ....

 

[Braincrank]

I had a new radiator fitted about 2 years ago .