Farmall M Engine Rebuild

Alright guys I?m really hoping y?all can help me out I?m still working on rebuilding my Farmall M engine. I am working on honing out my cylinder sleeves right now they were egg shaped and I have one trued up now my clearance is about .0015 I know that the ideal clearance is around .0020-.0040 but the problem I?m having is that I checked the ring gap in the sleeve I have honed and its about .020 which according to the service manual is the max spec for the rings but it don?t make sense how my sleeve to piston clearance isn?t where it needs to be yet and if I continue to hone my ring gap will only increase. This is a tisco rebuild kit should I contact tisco and ask what their spec is for the sleeve to piston clearance and ring gap clearance? I measured the old sleeve to piston clearance and it?s .0045 and the ring gap is .042 so I know whichever way I go it will still be tighter than it was. I have an extra tisco sleeve that I cracked and I measured it out of the block and the clearance piston to sleeve is only .0015 this has got me attaching my head how to best configure this engine all help is appreciated!
 
You hone to get piston to cylinder clearance, which I think would only be a few thousands.

You do not hone to set ring gap, you file the end off the ring to set that gap after the piston to cylinder gap is set, that should be about .004 per inch of bore, so .016 on that.

It is important to make sure the ring is square in the sleeve when checking the gap.
 
I?ve heard of people having to hone tisco sleeves to true them up and mine were far enough out I had to I was honing to get the right piston to skirt clearance not for ring gap but I checked the ring gap while I was at it to see where it was at so far
 
I hate to say it, but you are probably better off to take block to machine shop and have the sleeves installed. They will check the bore of the block with no sleeve installed and make sure it's true. These old blocks have been hot and cold so many times they tend to be untrue. Sometimes they will bore block and install a liner your sleeve can be inserted into. When you insert a new sleeve into a distorted hole, you can run into problems. Otherwise, hone sleeves with a rigid hone to get your piston clearance right and that's all you can do. Hope this helps!
 
Yes that does help my sleeves went in fine and I have used a rigid hone to true them up I?m just kind of stuck on what to do next cause if I continue to hone to get the recommended .0020-.0040 clearance at the piston to sleeve then my ring gap will increase and be out of spec so I?m kind of at a loss. I remember reading someone?s post that said they recommended .0035 clearaance and I wonder if I just go up from .0015 to .0020 my ring gap shouldn?t increase a whole lot
 
I also just measured my ring gap on a sleeve I haven?t yet honed and it appears to be around .020 but surely this kit doesn?t have a ring gap that big??
 
I see .020 is at the high end of what i would want for ring gap, which would be .004 - .005 per inch of bore, so 4" bore = .016 to .020

I looked back through old posts, and think that .006 - .010 should be about right for the minimum piston to sleeve clearance.

Again, if the sleeves are not round when installed, you have a different issue.

Comments from other posters are welcome, as I am guessing.
 
Most likely its the cylinder bore thats egg shaped distorting the sleeve. Ive installed those Tisco kits before, but never had any problems like that unless the bore was out of round. As for the specs, thats interesting, and at this point, I would contact Tisco.

This is one reason I started letting my machine shop do all that dirty work.
 
That's the trouble with the new aftermarket stuff now days it's all cheap made
no matter what you're working on. I've had this problem time and time again even after having blocks bored at a good machine shop. The only solution you have to do it right is to either buy oversized rings and file them down or have a custom set of rings made to get the right ring gap. I do not trust any rings that come with the pistons to be gapped right.
Everytime I check them right out of the box and after fresh bore job they already have way too much ring gap. Usually already at the high spec limit. I honestly thing they through whatever rings they have in the box and pass down the crap to poor consumers like us. There isn't any quality anymore cause no one cares about quality just quantity quota. Buy you a good ring file and file to fit your rings. Also the pistons need to be honed to fit the sleeves they will be going in, rings gapped to each piston and every thing marked so to make sure it all stays matched together. Custom fitted is the way to go that way you know exactly what you got. Remember ever .001" of piston clearance equals .003" ring gap. Hope this helps and I did not attend to step on any toes.
 
question for you... how did you check the ring end gap??? wondering because in your statements you are not doing it correctly. end gap for that engine is .012-.016 max. also you cant hone an engine sleeve to true it up with just a deglazing hone.
 

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