FAQ  •  Register  •  Login

Wrist pins a tight fit

Moderators: Curt!, Pa



Posts: 7

Joined: Sun Sep 13, 2009 12:16 pm

Post Thu May 17, 2012 8:56 am

Wrist pins a tight fit

Any thoughts on how tight is tolerable for the wrist pins? I've got one that is a little too tight for the piston to "fall over" from its own weight, and the other is tighter, I can move it by hand, but there is definitely some resistance, about like opening a two liter bottle of carbonated beverage. If this is too tight, can I hone the connecting rod bushing with a socket wrapped in emory cloth, or some other method to avoid a trip to a machine shop? All the parts are new, probably repro.


Mark Robinson


Site Admin

Posts: 5437

Joined: Sun Mar 12, 2000 1:01 am

Location: Ohio USA

Post Thu May 17, 2012 5:40 pm

Re: Wrist pins a tight fit

Run the correct size reamer through them.


Posts: 386

Joined: Fri Nov 30, 2007 7:24 pm

Post Thu May 17, 2012 8:15 pm

Re: Wrist pins a tight fit

The pins need to be a slip fit in the small end bushings and a light press in the pistons. If the pistons are warm the pins should press in by thump pressure. The pins should slide through the small end bushes with no slop and very minimal drag. If dropped in on end they should slide through by gravity!


Posts: 36

Joined: Wed Jan 20, 2010 9:52 pm

Post Sun May 20, 2012 5:46 am

Re: Wrist pins a tight fit

I have used a brake cylinder hone to ease that last half a thousandth out of those bushes.
Run it slow and real careful and check for size very often, it only takes a few turns to knock off the high spots and free up the fit. Use WD40 as cutting lube.

Return to 45 Flatties

Who is online

Users browsing this forum: Bing [Bot] and 3 guests

Powered by phpBB © 2000, 2002, 2005, 2007, 2012 phpBB Group.