Piston clearance question

Can anybody tell me what the piston/wall clearance should be for an International 856 with a C-301 gas and .060 overbore should be? I have lost my IT manual.

Mike,I think I read on here that its .003,for each inch of diameter

jimmy

James, thanks for the reply. I have seen anywhere from .001-.005 per inch of bore. Trying to pin down a number but I think I am confusing myself more than anything.

nope , thats ring end clearance.
the piston to skirt clearance is something like .0015-.002 . (thats my guess).

Ya want about .004 skirt to wall clearance Best way if fit each piston to each hole with a inside and outside mic. because each piston will vary and some i have seen vary a bunch lately.

Go with the Vet, that is really close to factory fit. I have measured a lot of new pistons in unworn part of the bore on those 221, 263 engines and they run .0035 to .004. We had a lot of trouble with the sleeveless engines where the shop doing the boring would not fit them to our specs and led to scuffing and scoring pistons. So, I honed them out to suit myself. The silly service manual shows from .0015 to .004 I think but then shows them fitting them with a .004 ribbon gauge.

This topic brings to mind a problem I encountered about 20 years ago on a 1690 Case (David Brown) 6 cyl. diesel.
Farmer brought it in for a rebuild. It's an un-sleeved engine, so I ordered 6 new pistons from Case, and took the block to the machine shop to be bored out so they could press in liners. Mfr. recommended .005 piston to wall clearance, so we went with that. Put the tractor on the dyno and within 5-7 minutes it ran tight and stopped. Disassembled and found 6 scored pistons. Re-did everything, and got 6 new pistons, and the same thing happened again. Machinist and I were pulling our hair out. We called David Brown in England, and they told us "Yes, we know there is a problem when rebuilding those motors, but we can't pinpoint it."
We ordered 6 new pistons, and while I was checking them with the micrometer, I picked up one of the previous pistons and discovered that it was .005 larger than the brand new one.
Turned out that the odd alloy that David Brown was using for their replacement pistons, caused the pistons to "grow" .005 and "set" at that dimension. The cure was simple. We set the wall clearance at .010 and put her on the dyno. The engine sounded real scary for about 4-5 minutes, and then slowly it quieted down and ran fine.
The machinist told me last month that he's done 9 engines like that since, with no problems

I had a machine shop in the 1960's -- 1990's. Zollner made most of the pistons on IHC engines. I remember the C 301 gas & LP as having a problem scuffing on the # 5 & 6 cyl's. Either IHC or Zollner had a service bulletin that stated increase # 5 to .005 & # 6 to .0055.?? I know we determined they diddn't have enough cam grind in the piston skirt. We bored & honed to their recommend specs, then put a Pefect Circle knurl on the skirt to bring it back to around .004. The knurl helped retain the oil on the skirt of the piston.Never had another engine score. I hope this helps. They only gave trouble doing the heavy field work. When you get your tractor running take a temp heat gun & see how much hotter the back cyl's run. Make sure you have a "A" plus radiator. Are any of your radiator shops using flow test equipment? I plow with my antique tractor & if you get the antifreeze mixture over 50-50 It doesnt cool as well.

another post mentioned about pistons expanding after being run ,ran into a similar problem with some trw wannabee kits years back that were made in mexico ,pistons would shrink and bind on the wrist pins and chatter like a monkey after it was run let cool and restarted,bad feeling knowing that the engine you just put in was to redo with free labor of coarse they warranty the parts

Lot of good information. The problem we had at the dealership was getting good information when we were having problems with any thing. There was no direct line to the engineering department of course, so a lot of desk jockeys thought they had the answers. Their usual answer, no one else is having that problem. Well, usually, some time later a bulletin would come out and have a cure or correction for the problem no one else was having. I returned two sets of sleeves and pistons to supplier for a DT-466 that had less than .004 piston to sleeve clearance. Of course, no one else was having any problems with them(Red Power) when I talked to supplier and their supplier (Howards). I used a different mfg's set.