9 replies to this topic

[David Day]

I'm rebuilding my Farmall M Engine, had crank problems. Is it necessary to replace the pistons, I know I need new sleeves as it had been burning oil, ever since I've owned it. Just didn't know whether I really need to repalce the pistons or if it is just a good pratice. Also noticed in my reapir manual that it said the side of the rod that has the number stamper in the block and rad is on the camshaft side of the engine. Mine wasn't that way when I pulle dth pistons out. Any thoughts?

[DC Snider]

David,

If your sleeving the engine, then I'd order the pistons, rings and sleeves as a matched set. My engine didn't need sleeves, I honed it and put new rings back on the old pistons. As to the rod orientation...sounds to me like someone has already been into it once and put it back together incorrectly. Without out having a rod in my hands to look out, I'm not sure if the oil galleys were lined up, plus I don't believe the rods are exactly centered either...something makes me think the wrist pins may infact be slightly offset from the crank journals...

[David Day]

Do you have a idea about taking the head to a head shop and having new valves put in? I've measured the piston and it is right at 4" is that the standard size of the pistons?

[The Dukester]

I was taught and followed the rule that if the sleeves weren't worn more than .003 per inch of cylinder diameter, out of round more than .002 per inch of diameter or not scored so bad that the normal glaze busting/ honing couldn't clean it up, it would be okay to reuse the sleeves or not have to bore the block if there were no sleeves. Pistons have to have the ring grooves/lands checked for excessive wear and the skirt diameter measured for wear (not to exceed .002 inch per cylinder diameter). Of course a lot depends on how the tractor is going to be used after the repair/overhaul. If it's going to be subjected to heavy use and loads, replacement of all "borderline parts" is essential for the engine to last a reasonable amount of time. On the other hand, a tractor used for show, parades and general light occasional usage can have it's engine reassembled with "good worn but useable parts" and be reliable and last indefinately. Either way it's absolutely essential that the engine be reassembled correctly regardless of how it was when torn down.

[DC Snider]

David,

4" bore is "standard" for the late M's and Super M's using the C-264 engine, early M's with the 247 will measure around 3-7/8". Like Dukester said, I'd have it checked for bore and taper before condemning anything.

Whether or not to have the head done is your call. Simply lapping the valves by hand and readjusting the valves may be all that is required.

[Chickenhauler]

I was taught and followed the rule that if the sleeves weren't worn more than .003 per inch of cylinder diameter, out of round more than .002 per inch of diameter or not scored so bad that the normal glaze busting/ honing couldn't clean it up, it would be okay to reuse the sleeves or not have to bore the block if there were no sleeves. Pistons have to have the ring grooves/lands checked for excessive wear and the skirt diameter measured for wear (not to exceed .002 inch per cylinder diameter). Of course a lot depends on how the tractor is going to be used after the repair/overhaul. If it's going to be subjected to heavy use and loads, replacement of all "borderline parts" is essential for the engine to last a reasonable amount of time. On the other hand, a tractor used for show, parades and general light occasional usage can have it's engine reassembled with "good worn but useable parts" and be reliable and last indefinately. Either way it's absolutely essential that the engine be reassembled correctly regardless of how it was when torn down.

What he said!

[Allan in NE]

Most critical wear on a piston is inside the lands/grooves. They get sloppy from all that abrupt "direction changing".

Replace the pistons and do 'er right. Ol' sister will last another 60 years.

Allan

[DWV]

I'm rebuilding my Farmall M Engine, had crank problems. Is it necessary to replace the pistons, I know I need new sleeves as it had been burning oil, ever since I've owned it. Just didn't know whether I really need to repalce the pistons or if it is just a good pratice. Also noticed in my reapir manual that it said the side of the rod that has the number stamper in the block and rad is on the camshaft side of the engine. Mine wasn't that way when I pulle dth pistons out. Any thoughts?

If you hold the rod by the small end and let the rest hang down, the side that hangs lowest with the cap off goes toward the camshaft side. Would check the piston ring groves for taper and width. If you have 4 inch bore firecrater pistons they were hard on the top ring grove unless timing, fuel and load were kept in the correct range. Dave

[David Day]

Is there an easy way to remove the sleeves. I've seen some comments about using a block of wood. I'm assuming you you are supposed to drive it from inside the block to the top. The bottom edge is really small, how does one get a 2x4 block cut the precisely, when the edge of the sleeve is only 1/16th maybe? Is their a sleeve puller?

[ole three bottom]

Yes there are sleeve pullers available. I know there is a company that makes one that quite often has an add in RPM. But just to do the job at hand I would check with a local tractor mechanic and see if you could borrow or rent one they probably already have. A good sleeve puller makes easy work out of the job with out doing damage to the block.