Topic: More Speedo Problems
in Forum: C3 Driveline Components

Although my brake light switch is in close competition, I don't beleive anything on my car has given me as much trouble as the speedometer. After many replacements and rebuilds, I finally gave up and bought a brand new one from Mid America last year.
I wanted a Corvette my whole life, but I never dreamed of all the wonderful people I would meet because of it!

Moderator
Has he checked the speedo adapter, and verified IT is not the problem?
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

I wanted a Corvette my whole life, but I never dreamed of all the wonderful people I would meet because of it!

Moderator
If you (or your tech) has a borescope, you might be able to sneak a peek up in there and see what the drive gear looks like, and it's location. Remember, you're talking about a hole that's only about an inch in diameter, and it's not exactly in a "line of sight" location. It's possible the gear has moved on the shaft just enough to not mesh properly with the driven gear...or maybe they dint get it back in the correct location when they worked on it before. Like I said, the only way to know for sure is to look. A borescope might at least give ya an idea, without pulling the unit back out, but if the gear is out of place, broken, or otherwise damaged....out she comes.

Another idea...have your tech check the speedo "bullet"..the housing that the small(white) gear fits into...the bore in it may be egg-shaped, and allowing the driven gear to flop....
Marshall, here's a link to a parts breakdown on the BWST10 trans, with the speedo gear circled. It shows there are two snap-rings that hold the gear to the shaft...I don't remember ever taking them off, but I s'pose it's possible they are there. The speedo gear doesn't have to come off to repair/rebuild the trans, so I may have just never taken them off. This might be the problem...one(or both) of the snap-rings are out of place, damaged, or who knows what. That would allow the gear to move out of position, and cause yer speedo issue....if it is, you'll still have to remove the trans...

http://s77.photobucket.com/albums/j54/aapple2/Misc%20pics/350%20Trans/4speed%20stuff/?action=view¤t=bwST10.jpg
|UPDATED|5/24/2012 7:51:53 AM (AZT)|/UPDATED|
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"