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Old 06-11-2014, 01:43 PM   #1
rich weyand
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How to fix an NP203/205 driven gear?

Anybody know how to fix an NP203/205 driven gear?

There was a 90*, 1:1.300 drive adapter on the NP203, and I added a 10% reducer to correct the speedometer. Apparently it had 33s on it at some point. The two speedometer adapter doodads argued with each other and seized up, which cause the little insert in the end of the NP203 driven gear (which has the square-drive hole in it) to extract itself.

I think I found a 1:1.200 90* adapter to correct the speedometer in one step, but that doesn't solve the driven gar problem.

NP203/205 driven gears being impossible to find, I have to figure out how to repair this one.
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Old 06-16-2014, 04:30 PM   #2
rich weyand
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Re: How to fix an NP203/205 driven gear?

Well, it turns out the speedometer driven gear was OK after all. What happened: an AC Delco 90*-drive 1:1.300 ratio adapter and an aftermarket 10% reduction ratio adapter fought with each other and locked up. The speedometer driven gear, not to be denied, twisted the .104 square-drive key into a pretzel.

Oh, and the driven gear was 22-tooth, stamped "M". WTF? Had to have been replaced somewhere along the way, as the only one installed in 1978 was the 18-tooth stamped "H".

So, I replaced the two adapters with one AC Delco 90*-drive 1:1.200 adapter. It needed a .152 tang to .104 square-drive speedometer cable key on the transfer case end, and a .152 tang to .104 female sleeve on the cable end. There are some on ebay, but people are inordinately proud of them. I finally found them both with one vendor at reasonable prices.

So if you are looking for speedometer drive keys, sleeves, speedometer cable ends, ratio adapters, 90*-drive adapters etc., I can heartily recommend Texas Industrial Electric: http://www.texasindustrialelectric.com/ No on-line ordering or prices, but they are great over the phone, the prices were less than anywhere else, looks like they have about a hundred different drive keys, sleeves, and cables ends, the parts were in stock, they shipped next day (which they were apologetic about: "Well, you missed today's mail, so they can't go out until tomorrow. Just so you know."), and they sent the correct parts, Priority Mail, for $5.05 shipping charge. I called them Thursday, parts in hand today.

Hard to beat that.
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Old 07-02-2021, 03:56 PM   #3
oski6754
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Re: How to fix an NP203/205 driven gear?

UPDATE: I can confirm that Steve at Texas Industrial Electric is the man to talk to about speedometer ratio ratio questions/problems/adapter rebuilds. The man really knows his stuff. Great referral.
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