F20 bearing play in crankshaft???

Hey gang....
I hate too ask for help twice in one day but I ended up at my uncles house helping him work in his 39 F20. We have the engine on a stand and spent the day looking for a distinct "knock" in the engine while rotating it over by hand. We pulled the timing gear cover off, nothing......then back too the rear and removed the clutch, the flywheel (what a job...had too build a puller for that one)...and nothing there either. We finally found that the roller bearings in both ends of the engine has a little bit of play in them......seemd too be about 10 thousandths. This was up and down play as the crankshaft would move up and down this much.
I know that's not a lot but at one point in exactly the same place....(top dead center on 1 and 4) you could hear and feel that little play.
We thought we had a loose rod or wrist pin.....but everything checked out good there.

My question is:
Should there be any play in the crankshaft at all??? We're going too replace the end seals while its down and will replace the end bearings also if needed. The bearings look like brand new and roll smoothly......but the play has us puzzled. Any info. greatly appreciated. Thanks.

No, there should not be any perceptible play in the roller bearings. BUT, I don't think .010 will make a knock. At least not turning over by hand. And the tractor was still running the last time it was used. You could have a rough ball in the bearing making a noise. Keep looking, you will find it. I'm trying to think..... I had an engine a couple years ago that had a distinct clunk. as I turned it over by hand. I can't remember now what I found.

are you trying to find a knock that you heard when it was running or do you hear a knock just turning it by hand ? If its a noise running how loose were the rod bearings? Also look at the governor real good , the keyway slot in the gear gets worn and that gear can bang around and knock. I have had a couple of them that the keyway in the gear was really wollered out and they made a lot of knocking noise.

IH warrented the crank bearings for life Just call BR549

We bought this tractor too refurbish back too its original conditon....we're not going crazy with it but want it too look nice and run nice when we're done.
It was not running when we brought it home but after removing the head, the engine looked really good inside. This tractor had sat for a number of years and the fellow we got it from didnt have alot of info on her either.
The noise we're hearing right now is coming from the front and rear bearing being lifted up and down from the rotation of the crankshaft by hand.
When the 1 and 4 cylinder rolls past top dead center...that's when we hear the "clunk". Not real bad but we're used too building car engines and have never had this play in a crank.

Yeah, You probably want to change the bearings since you already have it apart. There are some pretty good buys if you know the modern number to watch for. I'll see what I can find.

If you have her tore down this far and still hear a knock, spend the money for new mains. Beats kicking yourself down the road...

I also would replace the bearings if you are this far into it. There should be no "play" in the rollers.

Now, for the "sound". I agree with Cowman, you would NOT hear that in the mains turning it over by hand. I thought I had a problem in my 1928 Regular with a sound in the engine when I turned it over by had. Turned out to be sticky lifters, and the sound was the lifter "snapping" back down against the cam. cleaned things up a bit, and got some ATF down into the lifters. Sound is gone.

I am not saying that is what your problem is, but not out of the question either. Also, check the rod bearings as well. Very easy to check.

Right. "Life of the tractor" When you take a tractor that has been "dead" for 30 years I think the warranty has expired. If the tractor had been in continual use you may have a case.

Tony,I put a F20 together that had been sitting for years,you could see rust around the mains,When I started it,it sounded like 20 bowling balls rolling down a lane,I started quieting down some,I traded the tractor and it has a buzz saw rig on it and runs very good.These motors are very forgiving and runs very well.The more you abuse them the better they run,and start

jimmy

why is everyone calling the ball bearing mains roller bearings?