My 250 Turbodiesel

[domtoni]

Put a post up and the problem seems to be an MFA. Mass air filter

Well, topped the overflow tank and it took 2 liters of water.

got the temp to 90C, and took it for a drive. The car started to loose power, and the water temp went to 120 C.

The car would not run over 20 mph. Turned on the heater and the temperature dropped to 90 C, like a rock.

Car ran well.

it seems that:
- the thermostat is sticking closed
- the car goes into safety mode

Does this sound like it is plausable? If not, then where does one find the MFA on an old mechanically injected car?

BEst
Dom

 

[television]

Put a post up and the problem seems to be an MFA. Mass air filter

Well, topped the overflow tank and it took 2 liters of water.

got the temp to 90C, and took it for a drive. The car started to loose power, and the water temp went to 120 C.

The car would not run over 20 mph. Turned on the heater and the temperature dropped to 90 C, like a rock.

Car ran well.

it seems that:
- the thermostat is sticking closed
- the car goes into safety mode

Does this sound like it is plausable? If not, then where does one find the MFA on an old mechanically injected car?

BEst
Dom

I do not think that you have a MAF as such, this though would not cause the engine to overheat, if you have a thermo fan the fault lies around there, any more details of what car it is, ie first six numbers of VIN.

malcolm

 

[domtoni]

Malcolm,

VIN is WDB2021 882F (ZZZZZZZ)

Car is a 1998 2.5 liter turbo diesel with the old fashioned mechanical injection.

Same motor that is in the sprinter.

Also above 70 MPH, the car does not have much power. Could it be an air filter or something else?

Ciao
Dom

 

[television]

Malcolm,

VIN is WDB2021 882F (ZZZZZZZ)

Car is a 1998 2.5 liter turbo diesel with the old fashioned mechanical injection.

Same motor that is in the sprinter.

Also above 70 MPH, the car does not have much power. Could it be an air filter or something else?

Ciao
Dom

Oh yes you do have a Maff, that will need replacement at some time, tell me please,is the fan mounted on the engine or the rad, I think it is on the engine.

Malcolm

 

[domtoni]

Malcolm,

The engine has a viscous fan, and two electric fans at the front of the radiator.

Thanks
Dom

 

[television]

Malcolm,

The engine has a viscous fan, and two electric fans at the front of the radiator.

Thanks
Dom

Your engine fan should cut in around 85C and is not doing that, the famous test is the carrot test, run the engine up to 100c and hold a carrot into the blades of the fan, if the fan stops it needs a new visco clutch, a simple job to replace if it slices up the carrot then its OK.
Re the electric fans, one is for aircon, the other should I believe come on at 100c, I will check later in the day.

Malcolm

 

[domtoni]

Malcolm,

While the car idled during the warm up phase, they were running. Something brought the temperature pretty quickly once I turned the heater on

Best
Dom

 

[domtoni]

Malcolm,

Just went out for a drive.

- car warmed up very fast
- got to 90 - 95C
- then it started to make almost a cavitating noise by the driver's side (probably water going to the overflow tank)
- temp shot up to 120 C
- I turned around, got home, water was back to 90 - 95C
- stuck the carrot into the fan, and it stopped

Both electric fans were going at a very high rate

Sounds like my viscous coupling is kaput

Thanks
Dom

Would appreciate any further ideas !!!

 

[230K]

Hi

I would pull the thermostat off and check its operation on a kettle of boiling water, thermostat should start to open at around 80 deg C. When you have the thermostat off poke your fingers in around to the back of the water pump and feel if the impellor of the pump moves when you turn its pulley if not then you impellor is shot on your pump and you need to replace the water pump.
Check out this link
http://forums.mercedesclub.org.uk/showthread.php?t=19958

Good luck

230K

 

[230K]

Oh yes you do have a Maff, that will need replacement at some time, tell me please,is the fan mounted on the engine or the rad, I think it is on the engine.

Malcolm

Television

What makes you think the 250TD in the c class has a Mass Air Sensor??
I am sure they dont but i have been wrong before.

230K

 

[television]

Television

What makes you think the 250TD in the c class has a Mass Air Sensor??
I am sure they dont but i have been wrong before.

230K

In my first post I did say that I did not think it had a MAF, and I should have stuck with it, I have answered to a similar thread today, and that one went OK. I have answered some 65 threads today, and most of gone OK. Sorry if I am wrong on that, but that is no excuse.

Re the good points that you have suggested, if the thermostat was put into boiling water,I thought that would that not destroy it, I always thought that the water had to be around 100c as once boiled they are U/S Yes it does seem that this is more than the normal over heating problems.

I will leave it to you, as you have hands on with this one, I am used to leaks but not the impeller coming off.

Regards Malcolm

 

[shaungriff]

hi television, you are right saying a c250td has a maf sensor on that year !! 1995-08/1996 has a map sensor then 09/1996 onwards has a maf meter according to my tech book. cheers shaun

 

[230K]

Hi

Can someone tell me or even show me where this infamaous MAF/MAS sensor is on the 250 turbodiesel C Class, im still not convinced.

It can be confused with the temperature sensor



230K

 

[mioba]

from the initial post, did you just top up with water or did you add coolant also!

 

[domtoni]

Guys,

Car is now operational. 230K was right. The water pump's thermoplastic impeller was in three pieces. Replacement bought from Eurocarparts has a metal impeller.

Also three glow plugs were burned and now replaced. Car runs like new.

Best
Dom

 

[television]

This one has turned an interesting one, Thanks too 230K he hit the nail on the head, this will be the 3rd or 4th water pump failure in a couple of weeks, I wonder if the very warm summer played a part in this.

Malcolm

 

[230K]

Guys,

Car is now operational. 230K was right. The water pump's thermoplastic impeller was in three pieces. Replacement bought from Eurocarparts has a metal impeller.

Also three glow plugs were burned and now replaced. Car runs like new.

Best
Dom

Dom

Glad you got her sorted mate.

Cheers

230K