Alternator cover screws

garncarz · Post by **garncarz** » Fri Jan 24, 2014 3:03 pm

Does anyone have a good part number or description for the three screws that hold down the alternator cover? The fiche says 93700-050-160A. That's what I ordered from honda but the the thread pitch was wrong.

Thanks.

OldStan · Post by **OldStan** » Fri Jan 24, 2014 4:24 pm

The originals that size (5mm) are a JIS thread different, than current metric bolts, no longer available from Honda. Someone else might have a source for them. I retapped to the current pitch (I went from the back side to get maximum thread) and it seems to work fine.

garncarz · Post by **garncarz** » Fri Jan 24, 2014 4:30 pm

OldStan wrote:The originals that size (5mm) are a JIS thread different, than current metric bolts, no longer available from Honda. Someone else might have a source for them. I retapped to the current pitch (I went from the back side to get maximum thread) and it seems to work fine.

JIS referes to the head slot, so not really the issue. I just measured the screw and its 12MM x 5MM x 0.9 pitch. So, you say that you retapped it to 1.0 pitch?

OldStan · Post by **OldStan** » Fri Jan 24, 2014 4:38 pm

JIS also refers to the pitch, just on some sizes the pitch is the same. 6mm and 8mm are the same, 5mm, 10mm & 12mm I believe are different.

Yes, I retapped it to the standard thread. You do loose some thread, but it's not something that has a lot of pressure on it. I got the idea from someone else on the forum.

G-Man · Post by **G-Man** » Fri Jan 24, 2014 4:40 pm

Early JIS screws had different pitches too. Not just different heads. We are talking 50 years ago here.

G

48lesco · Post by **48lesco** » Fri Jan 24, 2014 8:33 pm

Page III of your parts catalog. If you don't have it, send me a pm and I will provide a pdf. The early 5mm screws are a slightly coarser thread.

48lesco · Post by **48lesco** » Fri Jan 24, 2014 8:46 pm

Another thought, most tap and die sets have both the M5x.8 and M5x.9 die for some reason, and I have successfully "converted" new .8 pitch screws to .9. As OldStan said, not much stress on that part either way. This way though, you don't modify an original part and I'm not sure if that's important.
-48