124 Fan Clutch Allen Bolt-Left Hand Thread?????

[jim16671836]

I have tried to remove the fan clutch allen bolt with no luck...it has a arrow pointing counterclockwise....I tried to loosen it with a air impact wrench by trying to turn the allen bolt to the right...All I accomplished was rounding out the allen head bolt....Is this bolt left hand or right hand threads...what is the arrow for...I am just in the middle between genius and idiot.....thanks for any help or suggestions...Jim

[haasman]

counterclockwise

Haasman

[cc260E]

Originally Posted by jim16671836

I have tried to remove the fan clutch allen bolt with no luck...it has a arrow pointing counterclockwise....I tried to loosen it with a air impact wrench by trying to turn the allen bolt to the right...All I accomplished was rounding out the allen head bolt....Is this bolt left hand or right hand threads...what is the arrow for...I am just in the middle between genius and idiot.....thanks for any help or suggestions...Jim

It is a normal right hand screw, it is a 10 minute job the trick is to have the tool to block the pulley (rod 6mm diametre).

[John H]

I'm in the midst of changing out my fan clutch on a 300e.

I pulled the radiator to make the job a bit easier. Made a tool to hold the pulley that worked great. Unfortunately I ended up rounding out the 8mm cap screw with a snap-on driver. The car has 210k miles and I think someone replaced the unit once already - and over tightened - as the clutch on the car is a Behr. Anyone have an idea what to do next?

[GVB]

Go get a torque type socket, hammer that in and try it. Keep the socket perpendicular with the bolt. If all fails, get two very big pry-bars, and use some grunt, the whole thing is a pressed in bearing, and will pull out. I would recommend that you find a Mercedes shop that is familiar with doing something like that. You could cause more $ in messing something up. I have seen this too many times.

[Ron in SC]

I try a sears bolt out to remove it. Probably size #9 or 10 would fit.

[jim16671836]

I used a larger nut and slid it over the bolt and welded it together and used a rachet and socket.... I have had to do the same thing on a couple oil pans...Jim

[A264172]

Or you can (order new bolt from dealer 'now' BTW if you haven't already) drill it out, if you can go straight in at it with the rad. out. This might be the eaisest... 20ish minutes and garanteed success with a common tool. If there is something still blocking access, you may need to take off the fan blade (3 bolts) and remove the fan clutch bearing bracket 'which holds the fan clutch to the block...' (4 bolts) and the coolant hose (across the bottom of it) to get a better approach.

[John H]

Thanks for all the tips!

I thought of going with an easy-out and will buy the correct size and try this next. A torx is out as there is not enough room to swing a hammer due to the AC condenser (unless it can be moved out of the way). If the easy-out fails I may press off the bearing or borrow a friends mig and do the old "buzz a nut on" thing. I just hate when a 15 minute job turns into a 2 hour one.