Hello again everyone,
I just got this car a few weeks ago,It is a 90 300e 3.0 and I changed out the radiator because the other leaked after hitting a wild hog the first night I drove it home. The pig did not survive but the car did.well almost,After changing the radiator I took it and had it flushed as the car was still running hot when running the air (up around the 100 mark) and stopped in traffic. And the air would stop cooling when it did.The fan(clutch fan) seems ok,the mechanic said that the passengers side fan was not running with the air on but the drivers side was.As far as he could tell the fan never did come on.After the flush the car seems to actually run hotter faster then before.I do not know why.I had read about resistor's and fuses but being new to the car I do not know where to look and if this could be causing the problem.I live in florida where it is usually around 90-95F temp.Any ideas or pointers and experiances would be appreciated. Please detail the diags of possible. thanks again
James

 

Oh I forgot to mention,When I was changing the radiator I turned the heater on full and I never got heat out of the vents.I had read somewhere the you needed to bleed air from the system somehow(related to aux)and something about an aux water pump.where is this and how would you do this or check this and Could this also be related?
thanks

 

I have a 1990 300TE but I am afraid I don't know respond to a hog hitting related issue...sorry...

 

OK,Found out that if I unplug the sensor screwed into the head(two wires,two posts) that the fan comes on high.But does that mean that switch/sensor is bad? I need help figuring that out.
thanks

 

yes...you very well might have to bleed the cooling system after those kinds of repairs...almost certainly..otherwise there are air pockets intersperced with the coolant and air heats up much quicker than the coolant...does the temp gauge jump up and down from time to time?

 

No,Not that I notice.What would be the proper procedure for the bleeding/burping the system and How about the sensor that triggered the fans when I unplugged it.How do you diagnose it or the resistor? Also a note about the heater. When the temp is up and I turn on the heater I get no heat.I had read somewhere that you have to bleed or burp the heater to(aux pump I think)How do you do this and where.

Again thanks

 

well, as far as I know you have to have the heater on (to complete the coolant loop) and then warm the engine up to running temp and then bleed the thing. I have nothad to do this on my 300 (yet)so I don't know exactly where the bleed screw is but usually it's on the thermostat housing...there are a couple of messier ways to do itbut generally justbleed via the bleed screw...very similar to bleeding home radiators that clunk and stuff in the night ...open the bleed screw gently and waituntil pure coolant comes out...then close it and let the engine keep running and open the bleed again...bubbles are what you are looking for...once no more bubbles the system is all coolant...no air pockets. The important thing is to have the cabin heater on as that is part of the bleeding loop..gotta purge that portion of air as well...good luck...cliff

 

OK,No bleed screw at or near the thermostat.But Maybe someone can come along with the answers for the both of us.Have I got a pressure switch problem,or a coolant sensor problem (the one in the head with the 2 posts) or a resistor problem.
anyone know? and thanks cliff

 

sorry but I just checked...the bleed screw is on the thermostat housing assembly..no doubt about it...are you positive you are looking at the same thing?the bleed screw itself is like 2 dollars and the entire housing is around 15...cliff

 

OK - because I always question myself on these things I went out in the dark with a flash light and looked at my 1990 300e...the thermostat housing is the very first thing you see and the bleed screw is right on top of this very first thing...couldn't be easier to spot much less get to...it's right there!! so are you sure we are talking the same thing? cliff