1987 300E 103 Thermostat temp?
 

Hello


What is the stock rating for the thermostat for a 1987 300E 103 engine?


Is it 87 or 89 C? Also what does the value mean, the temp it starts to open or is fully open?


Thanks!!

As you are in a warmer climate to me and would go for a faster opening thermostat and go for the low number so it will open quicker . But this is the normal temp - Opening at 87 +2 C fully open 102 c but your in a warmer country to me and could be different .

The full open temperature isn't really relevant. 90% of the travel will happen at the nominal set point, which is always the start-of-open temperature.

I am in the SF bay area.

Last night I ordered a 87 tstat as well as a new housing cover with bleeder bolt.

I tried the 79 and 87, currently on the 87. I seem to recall the fan clutch stayed engaged more in the summer with the 79 for whatever reason. Been a while.

I have the 79C thermostat now as I'm in socal desert. The only reason I can think your fan engaged earlier is because the 79C opened sooner and allowed the hot coolant into the radiator and the heat coming of the radiator made the bimetallic strip flex and engaged the fan. I actually am using the 79C year round, not sure if that would be good for murphysf, but the 87C should be just fine.....although, you will be doing a lot of sitting and stop and go in the Bay area, you might consider purchasing both to see how it works. Don't believe you'll even be able to drive a mile or 2 at a decent speed without stopping up there.

Yep, I think the Sachs clutch was designed for the 87. I do not overheat, but meh. I am going to try that M104 pulley and go from there.

Will you need to change your belt size?

Let us hope not!

It was listed on the EPC and the most up-to-date pulley for my 04/1990 126.025. It does not have it factory. I will acquire a junkard unit and give it a whirl. EPC made no mention of a shorter belt needed, maybe that stock tensioner has enough slack to it to compensate.

A1042050210 is the pulley part number.

That part number shows a fan clutch pulley, not a water pump pulley.

Whoops. I forgot that bearing bracket runs the fan.

Still has to help I would think, moves more air at lower speeds. :confused: