Farmall 656 c263 engine sleeve letter markings meaning?

[littlefarmer]

Hello---hoping for some advice from any IH experts out there.

I'm overhauling my 656 C263 gas engine. I have heard a lot about the fitted sleeves that IH put in when the engine was built. And also about the letter markings stamped on the top of the crankcase head deck. A B C and D.

My tractor has one marked D, and the other 5 cylinders are marked C. Can anyone advise on what these markings refer to, as far as required sleeve sizes?

I've been trying to find this info, but without success. I'm getting the sleeve set from AgKits, and they have standard, .003 and also .005 and .O10 oversizes. I want to get the correct ones for this engine. Because I'm told that the standard sleeve sets available from suppliers may be too loose in the engine.

Thanks for any advice!

This post was edited by littlefarmer on 07/12/2023 at 09:16 pm.

 

[Janicholson]

The markings were used for the assembler during manufacturing. The native bores were not all identical. The person putting sleeves in had 4 boxes of sleeves marked A B C D each was slightly larger as the letters went farther. more like .001 to .0015 difference between them. It was cheaper than making both sleev and native bore perfect. Jim

 

[the tractor vet]

actually Jim the A B was one sleeve and the C D was the larger one . On the rebuild kits ya got today they are all A B sleeves and this is where the novice gets in trouble and stuffs a A B sleeve in to a C -D bore as it will almost fall in . It is a problem tryen to get the C D bore class sleeve from after market . It's always a hassle , This is one reason i have gone to doing the C263 to 291 over bore this was and option ya could do to a C 263 , BUT it requires Boring of the block and the sleeves had a wider top flange to fit the wide flange the 263 had . Next option is to take it out to a 806 gas bore and run no sleeves . BUT the down side is what are you going to run for gas ?????? Yes i am going to beat the dead horse on this if your thinking of WORKING that tractor .

 

[littlefarmer]

Thanks for the info. I'm having the machinist who is doing the block, checking the cylinder bores to determine the exact sleeve size needed.

He says he recently worked on another C263 engine, that the customer installed the standard sleeve set in. They fit loose from the start, and then one of them cracked near the top. The piston pulled the sleeve down and it hit the crankshaft. A real mess!

I really wish the sleeve vendors AND the manuals would make it clear, that these engine sleeves are a [i:654c4848f0]selective fit item[/i:654c4848f0]. Instead of just advertising "here's a sleeve set for a Farmall 656 gas engine". It would save farmers like me a lot of grief.

This post was edited by littlefarmer on 07/15/2023 at 11:21 am.