Fan clutch bolt

[4451533]

well.. it looks the easiest DIY..

Remove the fan.. but, the bolt, the allen 8mm, rounded, by the prvious owner.. and it tights..

Any suggestions how to remove it?

M119.972 engine [Admin edit: This is an R129 chassis, not W124.]

 

[IslandMon]

With a rounded Allen head bolt I typically hammer a male torx bit into the rounded head. In this scenario, you'll likely need to remove the radiator in order to have enough room to hit the torx socket with enough force to have it get a good bite. Hopefully someone else has an idea that would save you the extra effort...

 

[a777fan]

With a rounded Allen head bolt I typically hammer a male torx bit into the rounded head. In this scenario, you'll likely need to remove the radiator in order to have enough room to hit the torx socket with enough force to have it get a good bite. Hopefully someone else has an idea that would save you the extra effort...

I think you’re right Island… remove the rad, and hammer in a slightly larger torx head socket.

 

[daantjie]

You can also try to hammer in the hex bit again first if it is not too rounded. Make sure the cavity is nice and clean before you try the hex bit again. Sometimes you get lucky and the shock of the hammer taps makes the bolt break loose when you try again. Tough spot though...

 

[Jlaa]

With a rounded Allen head bolt I typically hammer a male torx bit into the rounded head. In this scenario, you'll likely need to remove the radiator in order to have enough room to hit the torx socket with enough force to have it get a good bite. Hopefully someone else has an idea that would save you the extra effort...

If you wanted to avoid that extra effort of removing the radiator, what if .....

you blobbed a bunch of 2-part glue (like JB Weld) on an 8mm allen bit (or slightly undersized torx bit), and shoved it into the rounded bolt. Let it cure overnight. Then the next day, apply torque with a breaker bar. Maybe it is worth a try?

 

[emerydc8]

Someone on the forum recommended these and I've used them a number of times over the years.

https://www.amazon.com/Neiko-04204A-Multi-Spline-Extractor-Increment/dp/B01KN9YVWA/ref=sr_1_5?keywords=allen+bolt+extractor&qid=1651819288&sr=8-5

In order to use them, you would have to remove the radiator. In any case, it might be worth getting some Liquid Wrench on it overnight.

 

[nocfn]

if radiator is original, just replace it all at once and be done. Tstat, fan, hoses and radiator.

 

[gerryvz]

If you follow the advice to drain and remove the radiator and pound in a Torx bit of slightly higher size into the hex-slot, you will have NO problem to remove the bolt.

Removing the radiator is a 15-20 minute job after draining it, honestly.

Provides an opportune time to drain and change out the coolant, and even your radiator and hoses if still original.

 

[4451533]

I already removed the radiator. I will try to put a socket with JB welding and try to loose it

 

[4451533]

 

[gsxr]

Now find a reverse Neiko to re-install!