Trouble with 62 Speedometer
#1
Instructor
Thread Starter
Trouble with 62 Speedometer
Look for help with driven gear and drive gear. I have a 62 4 speed and I can't get the speedometer to read. I can run the speedometer by attaching a drill on the cable at the transmission. So I know the cable and speedometer is working. I have changer the driven gear out and still no luck. Can anyone tell me what's wrong or what I am doing wrong. Also is there anything inside the transmission besides the drive gear on the main shaft?
Thanks
Thanks
#2
Instructor
I'm assuming that when you say 4 speed you mean the factory B-W T-10. It used (3) different speedometer drive gears with different diameters. It used a 6 tooth 1.92" dia. gear, a 8 tooth 1.84" dia. gear and a 8 tooth 1.72" dia. gear. You possibly could have a mismatch of the drive and driven gears. For example a 1.72" drive gear and a driven gear meant for a 1.92" drive gear. That is a .100/ side difference so the gears might not be meshing. autogear.net has a T-10 catalog that has a listing of what driven gears are to be used with their respective drive gears.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
#3
Instructor
Thread Starter
I'm assuming that when you say 4 speed you mean the factory B-W T-10. It used (3) different speedometer drive gears with different diameters. It used a 6 tooth 1.92" dia. gear, a 8 tooth 1.84" dia. gear and a 8 tooth 1.72" dia. gear. You possibly could have a mismatch of the drive and driven gears. For example a 1.72" drive gear and a driven gear meant for a 1.92" drive gear. That is a .100/ side difference so the gears might not be meshing. autogear.net has a T-10 catalog that has a listing of what driven gears are to be used with their respective drive gears.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
#4
Instructor
Thread Starter
I'm assuming that when you say 4 speed you mean the factory B-W T-10. It used (3) different speedometer drive gears with different diameters. It used a 6 tooth 1.92" dia. gear, a 8 tooth 1.84" dia. gear and a 8 tooth 1.72" dia. gear. You possibly could have a mismatch of the drive and driven gears. For example a 1.72" drive gear and a driven gear meant for a 1.92" drive gear. That is a .100/ side difference so the gears might not be meshing. autogear.net has a T-10 catalog that has a listing of what driven gears are to be used with their respective drive gears.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
I would disconnect the speedometer cable at the transmission. Gently insert something ( small screwdriver, old speedo cable end, etc. ) into the driven gear and see if you can turn it. Obviously if you can the two gears aren't meshing.
#5
Instructor
I checked the '61 Chevy service manual and the '62 supplement. The drive gear should be steel if it's original and is a "press fit". It doesn't use a spring steel type clip like the plastic type gears. Is the drive gear centered in the hole for the driven gear? In other words did it move out of position on the main shaft. The only other thing I can think of, is that the drive gear developed a crack/ split and lost the press fit on the main shaft. This could allow the gear to spin on the main shaft. Maybe you can do a closer inspection of the drive gear with the borescope while turning the driveshaft. If you can't get a good view of the gear with the borescope, the HF Feb. flyer has a coupon for a color remote camera. It's half price ( $70 ).
#6
Team Owner
Member Since: Oct 2000
Location: Washington Michigan
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There's a "large" and "small" steel DRIVE gear pressed on the output shaft, and two corresponding families of "small" and "large" plastic DRIVEN gears that mesh with them (large with small, and small with large). Small and small won't mesh at all, and large and large will bind up. See the tech tip below for all the details.
#7
Instructor
Thread Starter
I checked the '61 Chevy service manual and the '62 supplement. The drive gear should be steel if it's original and is a "press fit". It doesn't use a spring steel type clip like the plastic type gears. Is the drive gear centered in the hole for the driven gear? In other words did it move out of position on the main shaft. The only other thing I can think of, is that the drive gear developed a crack/ split and lost the press fit on the main shaft. This could allow the gear to spin on the main shaft. Maybe you can do a closer inspection of the drive gear with the borescope while turning the driveshaft. If you can't get a good view of the gear with the borescope, the HF Feb. flyer has a coupon for a color remote camera. It's half price ( $70 ).
#8
Instructor
Thread Starter
There's a "large" and "small" steel DRIVE gear pressed on the output shaft, and two corresponding families of "small" and "large" plastic DRIVEN gears that mesh with them (large with small, and small with large). Small and small won't mesh at all, and large and large will bind up. See the tech tip below for all the details.
#9
Pro
#10
Instructor
Thread Starter
#11
Le Mans Master
Short Driven Gear
The NEW repro driven gears (Muncie style) are SHORTER than the originals (t-10 style not available) used in your transmission. You will need to add the small shaft extender piece (sold by some vendors) to the new gear end for it to work properly otherwise it won't be long enough to reach your drive gear. Bet that fixes it for you. Pilot Dan
#12
Instructor
Thread Starter
Well I can not believe that a simple job is eating me up!! I verified the drive gear is turning. I installed the gear in the transmission and used a piece of old cable in the driven gear. Had the car started put it in gear and not only verified that it was turning but grabbed it with a pair of needle nose pliers. I couldn't hold it ensuring that it wasn't slipping. I hooked up the cable and the speedometer was bouncing. So I pulled the cable off and drove it with a drill and the speedometer ran fine. The cable is 62" bought fron Ecklers. I am thinking now the cable is to short! I am going to see if I can buy a universal cable and cut it to fit. If that doesn't do it I'll burn the car!! Simple job wow
#13
Pro
Well I can not believe that a simple job is eating me up!! I verified the drive gear is turning. I installed the gear in the transmission and used a piece of old cable in the driven gear. Had the car started put it in gear and not only verified that it was turning but grabbed it with a pair of needle nose pliers. I couldn't hold it ensuring that it wasn't slipping. I hooked up the cable and the speedometer was bouncing. So I pulled the cable off and drove it with a drill and the speedometer ran fine. The cable is 62" bought fron Ecklers. I am thinking now the cable is to short! I am going to see if I can buy a universal cable and cut it to fit. If that doesn't do it I'll burn the car!! Simple job wow
#14
Instructor
Thread Starter
Thanks for hanging in there whit me. If you need help with yours send me an email as I don't get of the website every day.
Thanks Again
Billy G.