MTFCA Forum

Well it always seem like when I tighten a castle nut the hole in the bolt never lines up so I have to back the nut off a bit to get the cotter-pin in. Now I know that the pin would have to fall out for the nut to come loose but I still feel like it's not tight enough. Am I being over cautious?

Never back a nut off. If too far from hole, try a different one or file a small amount off the back side.

Well that's a good idea.

Yup. What Mark said. In addition, if the bolt hole is above, or almost above, the castellation in the nut, put a thin washer underneath. Finally, use as large a diameter cotter pin as you can get to go in. Nearly all holes/nuts listed to take 3/32" pins will quite easily take 7/64". You want the pin to be tight in the hole.

Which is why I use a torque wrench and Loktite and forget the cotter pin everywhere except the axle.

IMHO if the manufacturer felt that a nut needs a cotter pin (more expensive then a plain nut) then it needs the cotter pin.

Try a different nut until you find one that lines up right. They can be swapped around and when you get to the last nut in the pile, you can shave off a thousandth on the underside of the nut (rub it on the concrete floor) and try again.

Mark Gregush wrote: ↑

Tue May 25, 2021 11:31 pm

Never back a nut off. If too far from hole, try a different one or file a small amount off the back side.

I just backed an axle nut off to get the split pin to line up. It made me somewhat nervous but I had already stood on a two foot breaker bar and didn't want to go any further. Now I'll redo it after a rub on a file.

Paul

The difference between castle turrents is only like 6 thou on bolt on 1/4-28 to like maybe 10-11 thou on the 7/16 or 1/2.

Tight and then a cinch to line up, you then over-pull on the wrench you just established a new seat path. Nut off and file is the only real way to do it right at that point. IMHO.

A old time T service bulletin trick is to take a file or hacksaw and mark a line in the top of the bolt aligned with the split pin hole. That way you can tell if you can align the castle with the hole or if you will have to remove a little of the back side of the nut in order to get proper tightness, ( torque ).

Well that worked. I never thought of filing the back side of the nut. It took a few tries but it lined up the hole.