Why do you want to go oversize? For a little more, or do you think the bores are worn that much?
i can tell you that a 5000 diesel I re-ringed had absolutely no wear in either the bores nor the big ends of the rods. And I do know how to read a mike.
Rings were worn, put in new, got new engine compression, instant starts, where I had 1 good crank before and battery was dead, and that because it took so long to get even a fart out of it.
Cylinders don't normally wear on these engines, just a bottle brush glaze buster was all I needed to get back to normal.
Think twice on this. If you have to pull it apart and mike the bores to see if you need bored out, do that before you automatically decide it MUST need it.
If you are going to get the engine rebuilt by someone else, well, some rebuilders are more reputable than others. They may say it needs it, even if it doesn't, nd charge accordingly.
Posts: 758
Joined: 3/9/2004 From: Swamplands of NJ Status: offline
George is right, why do you want to go oversize? Do you have deep grooves cut from a broken ring(s), scored walls due to no oil condition, uneven wear, etc? The 0.5mm or 1.0mm is not going to give you any noticeable increase in displacement if that what your after. If in doubt just do simple calculation using the formula for the volume of a cylinder. If you can still see the faint marks of original honing leave it alone and just have the cylinders re-honed by machine shop. You can do it yourself with one of those Lisle or Sears cylinder hone but the result will be far better if the shop uses Flex-Hone.
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