Neven,
Quote:
3/ I think your 0.12 is to high (and therefore out of spec) but until you put in new bearings and test it you won't know as measuring it now will bear no relationship to what it will be when you disturb it as all the wear in the journal/bearings and teeth will be reflected in this backlash measurement
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Why do you think it is too high and therefore out of spec? The largest of these numbers in the book is 0.049 mm, or 0.0019". I find it hard to believe that just under 0.002" would be a reasonable number as a wear limit for backlash for these gears after 80K miles or so. As I've said, I don't think the installation numbers in the spec book table are vaild as a wear limit.
The thread seems to have wandered off from my original questions. I understand the differences in the tolerances of the various components at play here. 1) the crank gear, 2) the intermediate gear, 3) the case,and last (and least) the bearings. In fact several different combinations of these different components were allowed (save the bearings), and the installation tolerances for these combinations are listed in the spec book.
I don't know which of us is correct at this point, but it is apparent that we are seeing the tolerance numbers in a different light. I am seeing the numbers as installation tolerances, and you are seeing them as wear limits. As the book is not clear on this, I still waiting for someone to step up to the plate who has more experience than you or I, and set me straight.
I see the numbers in the light of the way pistons and cylinders are treated in the spec book. Install tolerances are given for the pistons and also for the cylinders. Comparing these numbers against each other gives another set of numbers, the installation running clearances, also found in the spec book. But the book goes further and gives the wear limits, being a comparison of actual measured piston dimensions against actual cylinder dimensions. So it is pretty clear that there are two kinds of limits for P+C, the installation limits and the wear limits. The book is clear on this issue.
Another point of logic I neglected to mention: a wear limit is stated as one number, not a range of numbers. (It has no meaning to say "I'm going shopping, but my expense limit will be no more than $20 to $40.") Another point: why would the book give a wear limit on the intermediate gear wear
and also the backlash? Which takes precedence over the other? (Since both are measurable, a wear limit for the backlash would seem to me to be more meaningful, but the book doesn't do this.)
The case of this engine has never been split, leaving out the possibility of an aftermarket line bore figuring into the mix.
The bottom line for me is that I am seeing only one wear limit for the crank/intermediate gear check, that of the intermediate gear, when measured per the spec instructions.
I will definitely re-measure the backlash with new bearings in place when I receive them, but regardless of how this new measurement turns out, it's not going to answer the questions in my original post.
Anyone else? Henry Schmidt? Steve Weiner?