Install a 80C thermostat and leave it in all year.

Also since you own a temperature reader I would scan the radiator looking for abnormally cool areas. Thats after you get the thermostat issue sorted out.
Check around or ask on the vintage forum what engine numbers you should be finding on the block and where they are. This should enable you to order up the correct thermostat if nothing else.
No sense trying to install one that does not fit although you should measure the step diameter of the thermostat housing if it has one. That way when you locate the suspected correct part you can confirm it by measurement. Also get a pictorial or make sure the thermostat is installed with the wax bubble on the hot side of the housing.
There have been many installed backwards on many cars over the years. Since there has been a lot of work over time done on this car It does still have it's fan shroud present?

Phil did not have that part number either' I am in Joliet Illinois' Whats an indy shop? At this point i passed on the information vin# and part # to a buddy of mine in europe. hoping he can track it down. I mean heck Hungary aint far from Germany, there books have to show something for this car i hope'

1982 280se I was finaly able to get a match for the thermostat after using the # off the housing, came in yesterday and turnes out to be the same 1 i already have that i could not get to fit in there, i just dont get it, this should be such a simple task, i have tried it right side up, up side down just cant seem to find a trick to get it to fit so the housing cover can be closed up properly. Could i be that much of a moron or is there something i am missing?

Indy or Indie = independent repair shop.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

1982 280se ;Well time to take it to an indy shop i guess before i take a hammer to the thermostat and the housing and make it fit. I dont care what anyone says that thermostat for it does not fit. A thermostat should be 1 of the easiest tasks on any car other then changing the oil and i cant even get passed phase 1 on this car.No wonder my father left it out, god bless his soul.

If you have the correct stat, changing it is pretty simple, really.

Just be careful with the housing bolts, they are usually corroded into the housing and require coaxing and penetrating oil to get out without breaking.

Tom W

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I have no problem removing the bolts, i have removed it now at least 10 times and keep having to close it back up with just the o ring because this thermostat that it matches up with does not drop in all the way like it should, so the top portion of the housing will not close like it should because its forced up by the themostat, I even got the thrmostat housing number that i used to match it up and it keeps coming up with the same thermostat. There has to be a special type for this car that fits, i know they made a lot of changes in the 80;s for these cars but why is it this hard to locate the 1 that fits in here. The most confusing part is that the housing# was used so you would think if that was matched up this would be a perfect fit'

A small indy shop could not figure this out either, so at least i know its not just me. The shop man said he will talk to some friends of his who are mercedes experts and will get back to me. What would hapen if i made the smaller circle on the bottom of the thermostat that goes in first by cutting it in to a smaller circle and that way i can make it fit and it would drop in further, would that make a diference in its function because its the top part that is sealed is where it openes up. Is it ok to do that if i had no choice about it, would it still work properly? Thanks Alex'

Pictures would help.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Well i think i have it figured out now' I was right about this thermostat not fiting the car, There were some cars that had used diferent housing, and dont sell just the thermostat.It has to be purchased with the housing all together for 170bucks. This information i have goten from the mercedes dealer in my area from a man that seems to know a lot about these old m110 motors. I asked him why would they not sell just the thermostat, his reply was thats mercedes for ya. So end of story is have to replace the housing just to get a thermostat in this car. Part# for this is 110-200-0415

He might as well said "Okay, now bend over the table and spread your cheeks for me!" There is no reason they can't sell you just a thermostat. Take it back, get a refund, report the dealer to the BBB and Mercedes and go to an honest parts place that will sell you just the $20 thermostat you need.

I am not crazy. at least not yet' I will try geting it from a friend of mine from europe see if he is right or not about having to buy the whole thing. I am just backed in to a corner because i have asked so many people about this and everyone keeps coming up with the same wrong thermostat for this particular 1982se so i dont know what to believe anymore. If i have to buy it just to take out the thermostat out of that housing just because it is diferent to put it in to mine sounds prety crazy but might not have any choice. Alex'

Buy one from this site.
http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=2BV1A96NK2C50TKBWZ&year=1980&make=MB&model=280-SE-003&category=G&part=Thermostat+Kit

I would love to if that would fit , thats the thermostat i already have. and thats my point that those will not fit this car. After weeks of searching this is the newest information i was able to get on this problem of 1982 280se some
has a diferent housing and is not posible to get themostat for them without buying the whole unit. This is what i was finaly told after searching all over. I already emailed phil in parts here also.