Farmall M Questions

45Farmall M · Jun 18, 2017

I have a 45 Farmall M with a 450 head. I have a stock c-248 block and I want to run fire crater pistons but I am not sure if I should run M fire crater or 450 fire craters. I have read that I could run 450 pistons sleeveless in an M but I am not sure. Any help is appreciated. Thanks-Ben

fastfarmall · Jun 18, 2017

4 inch is all you can get in there unless, u do some serious machine work to the block ! What u need the power for, a puller ?

rustred · Jun 18, 2017

my Super W6TA has 4 1/8 firecrater pistons and sleeves in the original block.

John M · Jun 19, 2017

As was mentioned, you cant run the 450 pistons without some serious machine work.

John M · Jun 19, 2017

The Supers have a bigger bore.

D Slater · Jun 19, 2017

Know of some that run the 4-1/8 pistons in a M block after the sleeves are out. Depends on how good or close to size the bore is without sleeves for correct clearance and use. hopefully some honing needed for correct clearance. Some used counter bore filler rings. One way to get the filler rings is to put the old sleeves in a lath and turn the ID at top of sleeve to bore ID. What's left is the filler ring after a little dress up. If engine needs another cylinder rebuild after that the block is bored for 4-1/8 sleeves if a good block. Have used standard elevation fire crater M pistons with a 400 or 450 gas head. Don't remember any work needed now but I may have trimmed some spots and forgot. Anyone making fire crater pistons for those engines now unless new old stock is found? IH made more than one type for 4 and 4-18 bore engines. Don't know for sure what's out there now. Have put a 450 LP head on 450 standard elevation 4-1/8 fire craters without needing to make anything clear.

High Octane · Jun 19, 2017

That counter bore ring is critical, and it's not fun. Cost wise comparison, by the time you try, its easy to use a lp head to make power, the costs are real close. I've done this procedure 20 times, and I recommend buying a 450 kit, have the block bored to fit the 450 sleeve. Truely, it's the best method for longevity. Jmho.

PretendFarmer · Jun 19, 2017

I would think by the time you get done paying for machine work you would be better off finding a C-264 and putting an overbore in it.

ih560 · Jun 19, 2017

All you have to do is pull the sleeves, run a hone over the block and the pistons will fit right into the parent bore. You can get some rings made pretty cheap to fit into the counterbore at the top of the cylinder so you don't lose any compression there, or have the hot spots. Machine the rings to be a slight press fit into the block and be flush with the deck. I have done this myself and it works fine. If you don't have a lathe, you could probably get a machine shop that isn't too busy to make a set of rings for pretty cheap. The first set I had made (before I got my own lathe) cost me $40.

Tom Dowling · Jun 19, 2017

a long time ago (30+ years ago or so) a machine shop dropped and broke my 264 block from my 400 and got me a 248 block with dipstick and bored the block for 4-1/8 pistons. I don't know what it would have cost if I had to pay for it.

45Farmall M · Jun 19, 2017

I have a 450 motor on the farm here. She's been seized up for about 7 years. That's where I got the head from. How hard is it to put the 450 motor into the M frame? Im pretty sure the starter is different? Not sure what else is different. But I have the motor on hand. How much do you think it would cost me to have the 450 motor gone through and resurfaced? I can do mechanical work myself but all the machining I would have to pay for.

D Slater · Jun 20, 2017

Same outside size of blocks, starter doesn't bolt to engine and the M one will work, crankshafts will except flywheels from M through 450. Unless getting near the last of M tractors made the M liftall housings don't clear a late M or SM 12 inch clutch on a 12 inch or 450 flywheel. Unless any block surfaces or bores are not true or rust pitted the 450 block shouldn't need machining.

High Octane · Jun 21, 2017

Tom, ouch. I had one fall off the stand n had to replace it. Was a $1000 Ooops for a new block.

Farmall M Questions

45Farmall M

New User

fastfarmall

Well-known Member

rustred

Well-known Member

John M

Well-known Member

John M

Well-known Member

D Slater

Well-known Member

High Octane

Member

PretendFarmer

Well-known Member

ih560

Member

Tom Dowling

Member

45Farmall M

New User

D Slater

Well-known Member

High Octane

Member

Similar threads