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printjunky
08-11-2016, 02:32 PM
A little background first. I'm doing a frame swap, so I figured "while I'm in there ..." I'd pull apart the gearbox. It definitely needs resealing. But more importantly, early into owning this (my 3rd) SIII, i did a 90 weight change, and found a single gear tooth in the bottom of the case. I did a careful comparison to the parts catalog and any other [pictures I could find and determined that it was most likely part of the 3/4 synchro, reverse idler, or the in/out gear. So I waited. And nothing happened. Well, now I know that it was just a stray (previous rebuild seems likely). Not a single tooth is missing that I can find. Now I know.

But there is (at least) one definite fault - the 2nd gear distance piece is broken (as seen above some of the gears).
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Most teeth/shafts, wear patterns seem fine, but I'd like some second opinions. Are there some doctors in the house?

The small gear on the layshaft has pitting, this is the worst tooth, not all are pitted.
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.... more to follow ...

printjunky
08-11-2016, 02:52 PM
One of the 1/2 synchros is munched on the little outside "ears", as pictured. All 3 on this one are peeled back like that. I'll likely just replace both.
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And I'm not sure about the wear on the 3/4 synchro (all that fuzz is paper towel bits).
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And I'm not sure if anything else needs particular attention. I'm particularly unsure about what I'm seeing on the "in/out" gear (and how that set's movement should feel).
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All of the bearings look/feel fine, though the output bearing spins in the housing, and I believe it's supposed to be loc-tited in there. Correct?

I gather, also, that I should change the 3/4 synchro springs/balls as a matter of course. Any other similar (maintenance) items that I haven't mentioned that I'm missing?