Mercedes OM 636 overheating

[vyv_cox]

A friend in Greece had a similar problem and needed a new thermostat. Like yours the housing was sealed and he went to a great deal of trouble trying to find a replacement. Eventually he found a screwed housing that can be disassembled for insertion of a new stat. It was in Germany but you may well be able to order direct. I think this may be it it you would need to check.
Régulateur d'eau de refroidissement (thermostat) 170

 

[kingsebi]

thanks vyv_cox. Unfortunately the one I have is a three way. Paul Rainbow posted a link earlier, but from the UK. Apparently hard to get anything delivered from the UK to the EU after Brexit - at least that's my experience.

 

[vyv_cox]

thanks vyv_cox. Unfortunately the one I have is a three way. Paul Rainbow posted a link earlier, but from the UK. Apparently hard to get anything delivered from the UK to the EU after Brexit - at least that's my experience.

I think you have been unlucky. I buy quite a lot of stuff from UK for delivery to France. Very rarely takes more than 10 days and sometimes only 2-3. Did get some Xmas cards at the end of January but parcels, especially with a courier, are much better.

 

[kingsebi]

Seems like I have been unlucky then... Anyways if it doesn't do any harm to the motor I will use it without the thermostat until I get a new one.

 

[PirateDamo]

Hi Mate, I'm new to this forum, I noticed your overheating problem on you om 636, I am now having the same problem, did you ever get it resolved, was it the stat in the end? I'd appreciate any tips cheers !

 

[davidivorwynphillips]

Interesting as I had this problem several years ago - there is a PBO thread entitled ‘A most curious problem’ from 2016. This started when I replaced my thermostat with one supplied by Westfield 4x4 (with three outlets). On running the engine subsequently the temperature rose well into the 90s but I noticed that when I released the radiator cap it fell to 75-80 deg. No apparent explanation and even Manfred from Westfield was stumped. So I drilled several small holes in the radiator cap to bypass the pressure spring. Since then the engine has worked perfectly with several hundred hours of use.

 

[PirateDamo]

Interesting as I had this problem several years ago - there is a PBO thread entitled ‘A most curious problem’ from 2016. This started when I replaced my thermostat with one supplied by Westfield 4x4 (with three outlets). On running the engine subsequently the temperature rose well into the 90s but I noticed that when I released the radiator cap it fell to 75-80 deg. No apparent explanation and even Manfred from Westfield was stumped. So I drilled several small holes in the radiator cap to bypass the pressure spring. Since then the engine has worked perfectly with several hundred hours of use.

 

[PirateDamo]

Thank you !

 

[kingsebi]

I bought a second hand three way thermostat that does the same that my old thermostat used to do.

 

[PirateDamo]

Thanks !