Having difficulty removing crank sludge trap plug

[Bob_Matthews]

Hi Geordie

I have just done my Mototrans crank and it does indeed have three sludge plugs as Jon says. They are radial to the crank centres and do an excellent job of removing any debris. Mine came out reasonably easily with an impact driver and good fitting flat bit.

To remove the welch plugs on either side of the crank pin - I drilled a small hole in the centre of one of the plugs and then screwed in a self tapping screw, I then used my claw hammer to extract the plug. The second plug was removed with the use of a pin punch and light taps through the crank pin - it came out quite easily. If I had been more careful, I would have drilled quite a shallow hole in the first plug and then would have been able to reuse it - but I drilled straight though into the void and ruined it!

The welch plugs are made from 10mm diameter aluminium bar so I bought a sample piece from evilbay for next to nothing https://www.ebay.co.uk/itm/Aluminium-Brass-Mild-Steel-Stainless-Steel-Rod-Bar-3-4-5-6-8-10-12mm/323175383233?var=512261555908&hash=item4b3ec100c1:g:jYUAAOSwUDhfZg4Q
I cut the bar to length (about 12mm?) and pushed it into the crank pin hole, I then used a 10mm pin punch behind the new aluminium plug and riveted the face of the plug into the countersink in the crank pin. I then tapped this plug back out again to clean up the top riveted surface.
Finally, I used bearing grade loctite on the plugs and tapped them home into position.

Hope this is of help.

[Geordie]

Thank you both Jon and Bob.
As I will be having the crank parted to fit a new bearing this is all most helpful.