Operating temperature

[Ernest]

Hi all,

I am new here with a 1992 E200, W124...1997cc.

I have just changed the water pump and the fan belt and the operating temperature seems to fluctuate a fair bit, themostats indicated temperature is 71'C...running temperature fluctuates between 70'C (during night time driving) to 100'C(idling, no moving)...

Fan seems to be working fine as anyone cannot overheard the fan's 'tune' whenit starts...LOL.......I am in Singapore, a tropical country (22'C to 33'C daily). Usual running temperature seems ok at about 80'C though...I am puzzled...no leakage is suspected as the resouvour is full every morning...I do not use any coolant in the radiator...

Please advice if this fluctuation of temperature is 'normal'? thanks...or any advice of what I can do? Alternatively, you can also write to me on lim_ernest@yahoo.com.sg...thanks you

 

[190]

Hi and welcome to the MB forum.

I have a 190D 2.0L, my temperature runs @ 85 when driving and when in traffic the gauge goes to 100 and then the fan kicks in and brings the temp back down to 80-85 degrees. I live in Scotland UK and the temp gauge has the readings in all weather.

Hope this helps.

 

[Mikesmerc]

My 230E 124 runs at about 80, but goes up to 100 in traffic the the electromagnetic fan cuts in and drops back to 80. Perfectly normal.
Mike

 

[jberks]

Ernest,
with an electrical fan, the temp does fluctuate. With a viscous fan, the fan is running all the time so the radiator always has airflow and the water flow is controlled by the thermostat. This is pretty inneficient though as the fan is permanently driven, even when it isn't needed - which is most of the time. With the electrical fan, the system has 3 states, stat closed, stat open and stat open with fan running. For the most part the middle state is sufficient as more than enough airflow is provided by the car's forward movement, the fan being needed only when the car is stationary. So long as the fan cuts in at 100 and the temp then falls back then as Mike says, it's perfectly normal.

 

[Ernest]

Fluctuating temperature is OK

Hi all,

Thanks for the inputs...really ease my mind for now...
As described, I had changed the water pump 2 weeks ago and I am monitoring the situation...

Thanks jberks for the detailed explanation...this really helps; looking back on my previous BMW 316i, which was fitted with a viscous fan type, the temperature during operation was rock solid even during heavy traffic: Thus, this E200 must be running on the electric fan...

Question, should I change it to the viscous type fan? Just to be on the safe side?? And how much would the hardware cost?

While I am here, I would like to check if anyone have a problem before in trying to open the engine oil cap on the top of the engine block?
I had just finished washing the E200 and was checking the dip-stick, oil level is ok though, However, as I was cleaning the engine area, I tried to release the cap of the engine block by turning it anti-clockwise but it just couldn't move...hmmm???

Question: is there a temperature controlled lock??

I had also bought a Hayes servicing manual for reference and I remember reading that the oil pressure meter will fluctuate proportionally with rev on the tactcometer...however, on my E200, when starting the engine, it is always rock solid at 3 bar...is this normal?

And finally, for now...can anyone tell me the usage, if any on the switch that turn on the headlights when turing clockwise...there are 2 step anti-clockwise but nothing seems to happen??

Thanks again...

 

[Mikesmerc]

Ernest the fan cooling system is fine leave well alone it seems pefectly normal.
The cap can be very difficult to open at times, a large rag on top seems to help me opening my one(more grip). Replace the whole cap, its cost is minimal. No temp lock
3 Bar is very healthy indeed esp when hot at idle, no worries.
If you turn the light switch anti c it turns on the parking lights(only when the ignition is switched off) first click for right side. 2nd for left. Not sure about left hand drives.
Regards
Mike

 

[shaggy]

my 1986 300 d runs at 40 when i have heating on in car and 80 when i dont, thats even in traffic or on motorway doing 90-100 mph :roll:

 

[jberks]

Shaggy, Sounds like your thermostat is buggered to me. The temp should be pretty static whether the heater is on or not, plus 40 is way too cold and the oil won't be doing it's job properly.
The heater matrix plus the main rad is providing too much cooling between them and the stat should be isolating the main rad. Apparently your's isn't. For the cost, against the increased engine wear, I'd be getting a new stat sharpish.

 

[Ernest]

Update on Operating temperature

Hello mikesmer/jberk...
Thanks again for your inputs and advice...

mikesmerc, mine is a right hand dirive...I will take your adice...
- will not change the fan...
- will try on the parking lights...that was what I thought it meant too...
- will not worry about the 3 bar pressure for now...
- will change the cap on the next servicing.

Singapore has all cars right hand drive, same like UK.

Regards to shaggy's comments...it sound rather strange...however, I will not be able to comment as we do not use heaters here...it is HOT everyday...we will need an air-con instead......however, shaggy, whatz the temperature when traffic slows to <15mph?? does it overheat? i.e >100??

Will be back soon; after exploring more...not sure isf anyone knows the specifications for petrol consumption for the E200?...I am getting about 7.5~8km/litre...

 

[shaggy]

cheers for that jberks new stat will be fitted tommorow

no ernest it stays at 80 m8

im in the amg 55 today cos the boss is away till tommorow evening so will play all today and tommorow

 

[shaggy]

not good :-x
my mechanic seems to think i may not have a stat in the engine he says its an old trick when you get overheating to take it out & i do use about 1 ltr of water per 400 miles but no oil in water & no water in oil so if its the head gasket its probably seeping into the top of the piston and getting burned away :-x
we will see tommorow when he takes it in for a check over and takes off the stat housing fingers crossed

 

[turnipsock]

http://forums.mercedesclub.org.uk/showthread.php?t=9476 you may want to have a look at this thread.

Taking out the thermostat is a dodge used by hillclimb cars, it increases the flow of coolant.

If the thermostat wasn't there, the car would take ages to warm up and would probably never get to operating temp on cold days.

It's important to understand what is going on, if you are driving flat out, the engine produces a lot of heat. If you then have to stop suddenly, that heat has nowhere to go as the radiator is not getting any air so the temp rises. This is where electric fans have a job. You can help things by turning up the heating and opening the windows and sunroof.

The worst thing you can do is crank up the air con and load up the engine, you may be cool, but the engine is throwing out steam...how many times have we seen people on the hard sholder with their bonnets up wondering how this happened?

 

[Ernest]

Buttons/user functionalities on the E200(W124)

Thanks again for the tips...

I had tried the parking lights...they are ok, works as specified.

I have a couple of 'stupid' questions if I can find some answers to?
- what does the buttons on the central console means...namely:
a. EC (environmental control?) what does it do?
b. the 'internal circulation' button;
c. and the other, err...window with 'smoke'??

When ever, i start the car, the airconditioner start automatically and of course the temperature controls of both sides? Just wondering what these vertical buttons on the central console means?

Had ran into a friend yesterday afternoon whom had owned a similiar model of E200/W124...there seems to be some other functionalities that are 'standard' here in singapore...not sure if it is the same over in UK??

Apparently, the following are some of the 'standards'??
1. When you lock the E200 with the key (not suing the remote); upon unlocking, and then holding the key on the utmost clockwise direction (3 o'clock); the power windows will be unwinded?
2. Central locking with the key works in 3 locations:
a. driver's door;
b. peseenger door;
c. the boot lock also activates the central locking mechanism.
3. I was also told that the car originally also comes with another key (without the central groove)....that enables one to use the car but not open the boot, as a standard for someone else to use your car but cannot access the the contents of your boot...

Sorry guys, I think I had also asked too many questions...and I feel that I should also contribute...can anyone tell me how would I get into questions that someone else post and if I can contribute our lovely encounters with our MBs??

To date, I have, I think more or less 'striped' the E200...cleaning our the boot area and the total interior...it seems to be ok for now...

BTW, the operating temperature seems ok now....fluctuating between jsut below the 80'C mark (75'C) to about 1/2 way between the 80'C and the 100'C (90'C)...seems normal enough, thanks to all.
- does the cooling system needs purging?

 

[jberks]

Ernest,
I'll try to answer your questions
A) EC is EConomy - actually aircon off - so light on = aircon off
B)The recirc is to get the airflow from inside the car instead of outside - useful for short periods if you're following a truck or driving past a smelly area.
C) Sounds like the rear window demister - probably not much use over there!

The 'standards' sound right - The key was called a chauffer or mechanics key
- would open and start it but not open the glovebox or boot. The locks were certainly that way on my father's S class so it's likely that the E followed. Not sure about the window bit - sounds about right - the Vauxhall cavalier used to operate that way - can't remember the Merc - give it a try!

If the cooling system is working ok - leave well alone - you could end up getting airlocks in the system. If it aint broke - don't fix it applies I think.

 

[300CE24Coupe]

Hi Ernest,

I have the same pattern of fluctuation in temperature as you do and from what I have read it is perfectly normal behaviour. One thing I did notice though is that while I was in KL last month, I went in many w124 taxi's of similar year to ours - and their temperature gauges did not move above 90 in traffic with aircon on full blast!
Maybe if you get a chance, pop over the boarder and ask the taxi drivers if they are using any tricks!