D4 6U engine over haul. How deep should I go?

There is frequently no clear stopping point. I would say just do the one and reuse your new gasket set unless your pistons have a lot of ring groove wear or the sleeves have a lot of "ring groove " at the top of ring travel.

I should have the specs on the crank bearing clearances etc at work. I am planning th plastigauge the rod bearings on our D7 this morning.

If it is a "Play Tractor", then do the one cylinder.
If your income depends on it, then go crazy and spend yourself into Debt.
My Opinion

I have what I suspect is the same issue on my 3J D2 but on #3 cylinder. If the liner is unserviceable, I plan to only replace that one. I've also taken this approach on the 8V71 in my logging truck which was a production machine and it was fine.
Cheers,
Neil.

I would part that engine and find another block or complete engine. Try Zimmerman Tractor 573-378-7210

How is the liner protrusion on the rest of the liners? If it is OK I would not disturb them and just replace piston and liner on the offending cylinder and match protrusion with the others. You can check the bearings with plastigage but there is no reason to believe they have failed.

How is the liner protrusion on the rest of the liners? If it is OK I would not disturb them and just replace piston and liner on the offending cylinder and match protrusion with the others. You can check the bearings with plastigage but there is no reason to believe they have failed.

Yes as most of us on here its a play tractor... But we do use it on the farm but mainly play clear a fence row or the growth around field where every year the plow inchs away from the edge of the field. The only problem with parting the engine out and find another block or complete engine you could end up with the same problem...

8c361 the liners of the rest the cylinders look nice and clean no scaring or major wear.. The tops of the liners have that slight ring grove but nothing extreme... The hour meter says 10380 hours it still counts as i run it but if has ever been changed idk.

:jaw:Holy crap i just got off the phone with my local cat dealer to buy everything to complete a overhaul is over $2800.00 thats more than i gave for the old D4.. A new liner is $109.21, a new piston is $135.89, and a ring set i did not hear them correctly but it was $75 or $175 :confused2:

Are these ok price's? is there a better supplier? How about anyone out there that as a used set?

Rings at $75 a hole equals $300 for 4 holes is about right.

Believe it or not ,Its cheeper to buy liner kits from Clevite ,than to buy individual parts . Especially if your talking liners or pistons