Its a 268 NH web block, the plan is/was to build it and put in in a 5000 basket case.
The original block had porosity, they had been adding water to it for some time, then water and freezing temps made it null and void. The rear exh port was completely plugged with carbon, cyl 3 was partial plugged..It had been run that way for some time..
The story I got with this used replacement block (short block configuration: crank,balancer,rods,pistons,cam,timing cover) was it was from a 7710 that had a cab fire. I decided while it was that far down to pull it apart and measure everything. Bores look like a simple hone and they will run, all bearings are std.
I got the pistons out and they had 2 compression and 1 oil ring, but not old headland style, and they are gunked up bad, piston #4 had the second compression ring stuck so bad I had to heat it to get it out of the ring land. I started trying to locate rings, every time I find 7710 rings they have 3 compression rings and 1 oil ring.
So I start chasing numbers, Bern confirms that the right pan rail numbers are NH numbers. 87840243 Part number 3m14 date code dec 14 93. 87840243 is the engine code for a 9030 versatile. So I look up 9030 and find 2 options for pistons and rings.. one of which is the same as the ones i have been looking for. NH is $95 per set, Reliance does them for 65.58 a set.
I was told these pistons are bi-directional pistons and have a higher compression ratio.
I hope someone can tell me if I can put standard 7710 pistons in it..
not looking for 100+ hp 75 would be plenty
Keep in mind, I wrench for the local Government 40+hrs a week and still help dad with the family farm. I do these oddball, weird, basketcase jobs on the side. Sometimes they are fun... Sometimes they make me want tear out what little hair I have left..