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Old 01-13-2013, 12:23 AM
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SpecialDelivery SpecialDelivery is offline
SWFL Benz Clubbin...
Join Date: Jun 2011
Location: Cape Coral, FL
Posts: 393
w140 Rear Crank Position Sensor / RnR nightmare

Everywhere I've read says this is a 10 to 30 min job. Yeah not on this car. The bolt came out ok but the sensor is in there tighter than a frogs behind.

I goosed er down with WD40 (fresh out of penetrating oil ATM) and got it to TWIST in its cylinder with a screw driver. It wont come out.

I tired to retreat...the car won't start.

Called Roy...he told me, yep, you've got to get it out now. Suggested a couple of things that I can basically characterize as creative applications of heat and force...but it's got to some out...or the trans has to be dropped.

He did say sometimes the end of the sensor swells...and it's a Royal PITA of the First Order.

SO DONT BELIEVE THESE YOUTUBE VIDEOS ALL THE TIME EH!!! (no im not Canadian I just like application of that word sometimes)

But it's got to come out...somehow. My friend had to walk home. I'm making coffee.

So I liked the idea of prying under it with a little screwdriver while I pulled on it...well i snapped off the entire plastic head of it leaving the magnet exposed in the center.

I got some more of the plastic broken off and got the pliers on the slid out.

Now I have the last what? five hours in this job and I've got the hardest part ahead of me.

This is a friends car I'm trying to help him out but I cant pay nor do I really want to learn how to do a trans R/R right now.

I got the top part of it broken, the magnet pin out of the center and now I'm about to try out a 2nd gen of a modified set of needle nose vice grips...( I tried to grind "hooks" into them.

BTW this is a 1994 W140 S500. There is almost NO room to get your hands behind the engine. The hose clamps on the false firewall are getting a knuckle and top of hand meat bonanza...and thats thru the Mechnix gloves...

Roy said heat might be my best friend here....I'm thinking he's right. I'm going to get the vac line to the trans up out of the way and see if I cant get some heat on JUST this part from underneath. Either that a pencil torch (dont have one)

To quote one of Adam Sandlers comedy routines...."F me in the goat A"
Adam Sandler - The Goat (Skit) - YouTube
caution on that language!!!

I want to say I will never attempt this again...but you know how us Benzaholics can be....

I HAVE been considering using some kind of puller, I just need to figure out a bolt big and sharp enough to tear into the inside of the magnet cylinder.
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

Last edited by SpecialDelivery; 01-13-2013 at 12:25 AM. Reason: noted the puller idea
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