Crank case bolt

[ClunkintheUK]

I am trying to split the crank case, but one of the 6mm bolts on the right hand side has been rather stubborn. The rest were fine with a normal socket, but the one at the back is more enclosed. I've tried a box socket over it, but I think it's been a little chewed up previously and my first attempt did not go well. It's the one at to bottom near the rear of the case. Any ideas for getting this out?

[DJ123]

Have you put some plus gas or other penetrating fluid on it?

[ClunkintheUK]

I've given it a few squirts of wd40.

[maviczap]

Wd40 isnt the ideal stuff as it isnt a penetrant.

As for the bolt, i'd whack it on the head using a centre punch just to loose the threads. Id also try warming the area around it, if you can

Id buy a deep 6 sided socket that grips the bolt on the faces, not the corners and use it with an impact wrench. I wouldnt use too much force, as its likely to shear.

[ClunkintheUK]

I've probably given a bad description. I don't think the bolt will be too stuck, the rest have been ok, but because this was more recessed I've rounded the corners a bit more. I got a box spanner, basically like a very deep 6 sided socket, but it's not really gripping the head of the bolt any more.

[maviczap]

Might have to cut a slot in the head if you can, but I'd still go for a quality 6 sided socket first, a box spanner will always be a sloppy fit

Pics would help

[punyXpress]

If it's the long burger that goes through both halves of the case, have you removed the nut from the other end?

[ClunkintheUK]

No its not the long one. I'll get a photo tomorrow. The main problem has been that my normal socket didn't fit straight over, but at an angle, it wasn't a problem for the 8 other bolts, but this is more enclosed. I need a thinner socket to get over it properly. At that point it may have purchase enough. Also not a bi-hex.

[atassiedevil]

Wera Joker spanner might help here.

https://www.youtube.com/watch?v=BvBmCqXDDdk

Either that or a good star socket that'll grip the sides, rather than the corners of the bolt, as already mentioned.

IF it's stubborn and of a small enough size, i've had success with a cordless drill/driver with adjustable torque, and turned the torque up slowly with a suitable socket adaptor attachment, it'll eventually "shock" it free.
Failing that impact driver would be my next port of call.
Alternatively drill it out, buy a new one, use molegrips to turn it out once apart.

[ClunkintheUK]

Got a 8mm deep drive with a 1/4" drive, came right out. Thanks for the advice Mavic. I have now discovered that one of my con rod bearings has disintegrated.

[Craig380]

Ouch, what happened? Is it the big end or the little end?

[ClunkintheUK]

Not sure exactly. it was on the big end. Took the con rod off and half the bearing shell was in pieces, seemed corroded and felt like there was grit in there too. Its also scratched the crankpin. The other one seems absolutely fine, though is now a little scratched from the grit of the broken one. I am just now trying to figure out what best to do.

[Craig380]

:( sorry to hear that