Thermostat replacement on om642 engine
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Joined: Apr 2007
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From: New Hampshire
'04 C320 4matic Wagon (sold),'15 E350 4Matic(sold),'14 E550 convertible,'20 GLC300
Thermostat replacement on om642 engine
I’m considering replacing the thermostat on my 07 E320 bluetec. Are there any guides or videos available? Everything I’ve come across is for the gasoline engine or for the older diesel engines.
thanks
thanks
Out Of Control!!
Joined: Jul 2003
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From: North Scottsdale, AZ
'71 Pinto
Part # 6422000415
Thermostat: http://workshop-manuals.com/mercedes...ce_and_repair/ + next pages.
Workshop manual:http://workshop-manuals.com/mercedes...ive_displayed/
Thread Starter
Junior Member
Joined: Apr 2007
Posts: 61
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From: New Hampshire
'04 C320 4matic Wagon (sold),'15 E350 4Matic(sold),'14 E550 convertible,'20 GLC300
Thanks Konigstiger. Looks pretty straight forward, how is that possible on a Mercedes. I will link this thread to the diesel forum.
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Junior Member
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From: New Hampshire
'04 C320 4matic Wagon (sold),'15 E350 4Matic(sold),'14 E550 convertible,'20 GLC300
I see your point about if it is a electro mechanical valve it could be the control unit at fault. Interesting that you found it listed as a valve as opposed to a thermostat, I’ve only seen it listed as a thermostat, and I’ve been to many different places. The work instructions Konigstiger forwarded also refers to the part as a thermostat and only talks about disconnecting the heater wires ,nothing about disconnecting control wires. Well I’ll find out soon enough the part is going in tomorrow.
Thread Starter
Junior Member
Joined: Apr 2007
Posts: 61
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From: New Hampshire
'04 C320 4matic Wagon (sold),'15 E350 4Matic(sold),'14 E550 convertible,'20 GLC300
Success! The part is indeed a thermostat. Ended up not installing it myself, because I was having other work done. The operating temperature is now rock steady around 90 degrees C, where as before it struggled to reach 60, this is according to the temp gauge on the dash. Fuel economy is up too, but it's a little early to victory there. Funny thing is I was getting poo-pooed by my mechanic because he had never seen one of these thermostats go bad and he had little faith in the dash gauge. The low operating temperature issue had been a slowly worsening problem over the course of 2 years, but like the frog in the pot it was ignored until this recent cold snap. Driving for 5 hrs back from "the outlaws" in outside temps in the teens (degrees F) and getting minimal heat in the cabin was my jumping out point.
Last edited by fatherhood; Jan 12, 2018 at 09:39 AM.
