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Speedometer gear

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DDelaney

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Hello all. This is my first post except for an introduction awhile back. I have been learning quite a bit on this wonderful forum. I have searched for a thread on the problem I am having but have not found one that may help me.
The speedometer on my '67B stopped working last week. The cable is not broken. The 90 degree drive gear on the transmission is functioning. I took the speedometer apart and the gear was very hard to turn. I was able to free it with a little squirt of Break Free. It was fuctioning by hand before I re-installed it this morning. It still is not working. How possible is it that the gearbox speedo drive gear is not working? Is there a way to check it by hand?
By the way the gearbox is later than '67. I do not know which year. All syncro. No dipstick. Fills up from the side. No overdrive. Thanks to anyone who would reply.
Darrell
 
It may be that the drive gear on the trans output shaft stripped the pinion shaft gear to the little 90 degree gearbox, due to resistance in the cable. If you can remove the 90 degree drive and turn the center shaft it fits into at the tranny, the gear is stripped. This may not be the case, just one other thing to check.
 
To me it sounds like the square end of the speedo cable has rounded out or the female square of the speedo head has rounded (probably the cable). If this is the case then you should put some long-lasting lubricant on the speedo like common "3-in-1" oil (I am guessing that Break-free will evaporate pretty quickly)and then put a short piece of electrical "shrink-wrap" or one or two wraps or electrical tape on the speedo end and gently reassemble them, should last for a very long time.
Bill
 
Disconnect the cable from the back of the speedo & see if you can hold the end while you drive up & down your driveway...if the cable turns, the gears in the trans are good....however, as above - check both ends of the cable plus the angle drive down on the trans.....if the speedo was 'stuck' it might've rounded off the cable ends or the plastic gears inside the trans...they're all available new or used.
 
Sounds to me like the little gear in the transmission is toast. I would undo the angle drive and spin it with a drill. If the speedo works, then there's your answer.
 
Thanks to everyone. Hate crawling underneath...not much room. Will be looking at the tranny for the answer. Should I possibly be looking to get another speedo just in case this one freezes up again?
Darrell
 
Not until you've found the SOURCE of the failure, IMO.
 
Steve_S said:
Sounds to me like the little gear in the transmission is toast. I would undo the angle drive and spin it with a drill. If the speedo works, then there's your answer.
Click to expand...

Does the drill need to be in reverse? I read that somewhere.
 
Thank you all. I found the culprit. The pinion shaft gear to the little 90 degree angle drive is stripped. I will have to locate another. Neither Mossmotors nor Victoria British list it in their catalogs.
Darrell
 
Glad you located it. Be sure all other components are free turning or a replacement will suffer the same fate.

Check with Tony "The Autoist". He may have one.
 
Thanks....I've bookmarked Tony's site.
I know the gear is shot but I need to pull it yet to determine how many teeth it has. The gearbox is later than '67 but I don't know how much later.
 
Darrell, More than likely you will be required to replace the angle drive. Tony may have a good used one he will part with reasonably.--Fwiw---Keoke
 
Yep - I've got good used ones
 
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