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Tach Drive Gearbox - oops

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emann

emann

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I just read on here yesterday someone's comment "if it ain't broke, leave it alone".

So of course, last night I decided to take my tach drive Gearbox off my Bugeye and grease it up since it's been sitting for 20 years. A little preventative maintenance on a part I know needs it.

Sure enough, the tach no longer registers a thing. Gearbox seemed fine when I took it off and went back on easily.

Is there something I could have screwed up? Can I fix this thing? The 2 gears inside look fine, spin nice. the input looks good. The output I can't see. What can I put in there to see if it's spinning?

And just in case, has anyone bought the $67 Moss one? Are they any good? Hate to spend that much on something that isn't built quite right.

The frustrations of a LBC. 2 nights ago was great, got the electric all working. Last night, not so good, screwed up the Tach, didn't get the Speedo working, adjusted the MC pushrods so now the Brake lights won't go off. Maybe tonight will be better.
 
I've got the Moss one on my car, it does work. These boxes, original or repro, are not particularly robust.
 
I know they aren't the best parts on the car, it's just frustrating that I broke it trying to do preventative maintenance to keep it from breaking,

I remember 20 years ago being absolutely THRILLED that we got the tach to work since we knew we couldn't get these gearboxes anymore.

I guess at least now, I can replace it if I have to.
 
Take it clear off and test it in your fingers. If it does indeed turn properly and it shoulc then the tac cable is not hooked up correctly or the end is not in the generator.

One step at a time. Check box out of car, install box to generator, check that it turns when engine runs. Check that the tac end is turning, Shrug
 
Jack, thanks.

I was hoping last night that I just had something not quite installed right.

I took the gearbox back off the car. I was able to freely turn it, but I couldn't tell if the output was turning (too hard to see inside). I guess I need to find something that I can stick in there (without screwing up the drive end) so I can tell if it's turning.

Is there a trick to getting the tach cable into this thing? I kinda felt that the problem was there. The cable end seemed plenty long, but I never felt as I put it into the gearbox that it was "engaging" into anything.
 
No trick, just poke and poke till it fits in, attach to the cable first then the generator. will take a bit of turning to get the generator end in the slot.
 
Sometimes when you insert the square end it doesn't quite fit in and binds, I would suggest playing around with both the little tranny and the cable. Good luck.
 
I found that if ANYTHING binds in the cable or tachometer, the output shaft of the gearbox breaks. That's the weakest point. I hope that didn't happen to yours, but it seems hard to imagine that the whole thing would go back together without the cable fitting into the square hole in the output shaft. The gearbox won't go onto the generator at all unless the shaft is mated properly.
 
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