Nice pics of good project! I keep promisin' my self to take pictures like that of one of mne one of these days . . .
One observation, and it's JMHO, but I don't think a crank is a place to skimp. Plastigauge is useful for a general evaluation of clearances at the outset and a final check when reassembling, but it's of very limited use in practical terms for finding out of round pins and the like. If you're going to have it out anyway, I'd suggest you get it to a shop and have them mic it to see just what shape it's in.
You might get away with just popping new bearings in. (I'll admit to having done it, but only after the shop cleared my crank -- basically the motor was badly stuck on the top end from neglect not long after an overhaul, and the bottom end was surprisingly clean. The shop measured up my crank and said it looked like it had been turned jst the week before. I only put the new bearings in bacuase it didn't make any sense givent he minimal cost to clap the old ones in as long as I had it apart.
I don't have the specs for your motor at hand but, by way of example, assume your good clearance on the rods and mains is in the range of 1.5 to 3.5 thousandths, and your initial evaluation with plastigauge is showing 7 with the existing bearings. You might be able to make up 2 or a little more, with new bearings, which would still leave you with too much clearance. If the bearings were wearing hard, so was the crank, and you wind up with the crank dimensions out in that no-man's land between multiples of .010 under and it will need to be turned down.
This is gettin' longer than I intended but there is one slim chance of popping in new bearings if they're still available. A shop, in evaluating the crank will measure it. The measurements will be what they will be, but lathe shops usually stamp a mark in the crank to show that it's been turned down and how far, and your guys will look for that, too. If the crank has never been turned and your clearance is a little excessive with standard bearings, IH used to sell a bearing that was .003 under (or over, as you wish -- another discussion!). Some folks have said that they used them at the factory to take care of cranks that were ground a little undersize in the manufacturing process. They were also used in maintenance to make up for light wear, so if that's what they find and everything is round, those bearings might work but, after that, you'll need a crank ground to .010, .020., or .030 under.
If you're doing that much work anyway, I'd have the pros evaluate the crank and make my decision from there.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Choosin, Mounting and Using a Bush Hog Type Mower - by Francis Robinson. Looking around at my new neighbors, most of whom are city raised and have recently acquired their first mini-farms of five to fifteen acres and also from reading questions ask at various discussion sites on the web it is frighteningly apparent that a great many guys (and a few gals) are learning by trial and error and mostly error how to use a very dangerous piece of farm equipment. It is also very apparent that these folks are getting a lot of very poor and often very dangerous advice fro
... [Read Article]
Latest Ad:
Sell 1958 Hi-Altitude Massey Fergerson tractor, original condition. three point hitch pto engine, Runs well, photos available upon request
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
