Right after I posted this my radiator exploded. The tank cracked along the mold part line. I put in a new radiator and while I was in there I noticed a few things. The car runs well and the temps stay between 80-100c.
My fans don’t seem to turn on. I searched around online and most people describe a system with two relays - blue and green that get messed up and the fans don’t go in fast or slow mode. The problem is my car is a late 97 and it seems to have a lot of 98 stuff on board. Particularly it doesn’t have the aux fan relays. I’m not sure how the car controls the fans but it seems to be done with a digital component (motronic?) somewhere.
Not sure where to start. I tried to take the connector off what looked to be the coolant temp sensor and it snapped in half. I gently put it back together and the car still runs without throwing codes and the gauge works. Not sure if this car uses two sensors one to do the engine control and one to do the aux fans. It does seem to have two. They’re pretty inexpensive so I’ll order both.
This one:
https://www.pelicanparts.com/More_Info/0115425117.htm?pn=011-542-51-17-M85&bc=c&SVSVSI=2615
And this one:
https://www.pelicanparts.com/More_Info/005153232864.htm?pn=005-153-23-28-64-M253&bc=c&SVSVSI=2615
Not sure which is which but they appear to be measuring coolant temp. Might as well swap since one is cracked and the other maybe old.
Another interesting thing I found is the sound deadening material in the trans tunnel collapsed down and was rubbing on the front flex disk. It made a buzzing sound as I drove around kind of like when we used to put cards in the spokes of our bicycles as kids to make motorcycle noise. It took a long time for me to figure out where the buzzing was coming from. It sound like it was a bad speedometer cable in the dash but this car has an all electronic speedo. The good news is I found the offending dynamat an cut it away from the driveshaft. The car no longer buzzes.
So things are really coming together. I think my AC will work better if my fans come on when I turn on AC. Right now they don’t and that isn’t right. It still gets cold but I think all flow is from the viscous fan clutch pulling air through.
While under the car I found I was missing a shift bushing. WOW there is no room down there to install one. The arm doesn’t come off. The press tool won’t fit in between the trans and tunnel. I managed to work it in with hemostats and a screwdriver. Luckily it is softer than the w123 style.
I’ll try to get some photos up of my shenanigans later. The car is nothing to look at. Just another champagne gold Benz with faded clearcoat. I think I have sunk about 40 hours of work into it by now with all my little jobs. It cost me $2000 and it is basically totaled by labor. I have about $1500 in parts invested. This includes tires and the new radiator which were bigger items. Perhaps I overpaid.
Well, I guess we don’t do this for the money. It’s the fun of getting things working again.