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Should I sleeve a D68U pony
Should I sleeve a D68U pony
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Hi. I have a D68U pony apart. It has standard pistons, for which I can get new rings. I can't get oversized pistons or rings from Cat (I only tried 20 o/s but I am assuming all oversized pistons and rings are out of production?). The bore is worn 0.005 over maximum,has a small amount of rust pitting (water got in) and taper/ridges where the rings have worn in. My choice is just to reassemble like it is, with new rings. It will have lower compression but I am guessing it would still do its job. Or with more investment of time I can sleeve it back to a standard bore and get it back to factory compression. Thoughts on the best approach? The machine will never do much work again.
I have 6 poney piston standar and 1 is .30
There's probably only one way to know if just rings is going to cut it, so it probably comes down to your tolerance for frustration if just rings isn't enough to get the job done - if you don't mind pulling it apart twice, and the extra outlay for the new rings that won't be used if you re-sleeve coupled with the outlay for the actual sleeving (and the new pistons from Hector (gemdozer), then go with sleeving (if that's even an option). That said, these engines seem to sometimes run on it seems almost no compression. Also, that said : ), an easy-to-start and powerful pony is a good thing to have. I know, not much help at all but perhaps food for thought : )
If it worth doing it’s worth doing right. Obviously you want it or you would not be working on it. And in my opinion it’s just to difficult to take them things out and in
New oversize pistons and rings are available in Australia for that pilot motor
Thanks Mike for that lead. I was indeed able to buy the oversized pistons and rings from Nornda, made in Australia, to order. I advised them to list CAT part numbers on their website so others can find them. Thats a better solution than sleeving it.
They're good too - I have some JP pistons in my 3J's pony
I sleaved a pony for a 4R D6, but my cylinders were farther out and had substantial rust pitting. I didn't have much choice. The good thing is I'm now back to standard and that pony will (hopefully) outlive me.
At the time I made the decision, I couldn't source oversized pistons or rings.
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