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#67199 10/16/2006 2:37 AM | Joined: Oct 2006 Posts: 31 Apprentice | | Apprentice Joined: Oct 2006 Posts: 31 | Hello,I just installed the orig. speedometer in my 49 chevy truck and it worked the first day then quit.I checked the speedo and the cable and the drive gear and they all seem ok.However,I stuck my finger in the transmisson hole and found that I could slide the worm gear front to back and spin it on the shaft.Is this gear held in place by a key or a pin?What is involved in fixing it?Thanks for any help,Chip | | |
#67200 10/16/2006 10:26 PM | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 |
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | |
#67201 10/16/2006 11:44 PM | Joined: Oct 2006 Posts: 31 Apprentice | | Apprentice Joined: Oct 2006 Posts: 31 | I'm sorry Wrenchbender.It's a 3 speed. | | |
#67202 10/17/2006 6:01 PM | Joined: Jun 2000 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2000 Posts: 50 | I can speak for a 51 3-Speed on this problem. Between the speedo gear and the U-Joint yolk on the tranny is a metal sleeve. When the u-joint yolk is tightened on the tranny shaft it presses against the sleeve which in turn squeezes the gear agains a shoulder on the tranny shaft holding it in place. I would first loosen and slide the torque tube ball back exposing the u-joint and make sure the u-joint bolt yolk is tight. You may have to dissasemble the u-joint to get a wrench in there. If is is tight I would pull the yolk completely out of the tranny, and insert very thin steel washer between the sleeve and the yolk to give it some more squeeze when I retightened the yolk... Bug
1951 Chevrolet 3100 AD Pickup
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#67203 10/18/2006 12:42 AM | Joined: Oct 2006 Posts: 31 Apprentice | | Apprentice Joined: Oct 2006 Posts: 31 | Bug,Thank you very much.That was exactly the info that I needed.I will try that.I'm just starting this project and I'm sure I'll have many more questions! Chip | | |
#67204 10/18/2006 3:34 AM | Joined: Nov 2002 Posts: 12 Junior Member | | Junior Member Joined: Nov 2002 Posts: 12 | I had a similar problem. The yoke bushing was worn and caused some vibration which must have worn the sleeve that pinches the speedo gear. So the gear would only spin the speedo on deceleration not acceleration. I just ended up putting in another lower milage transmission. The thin shim stock washer idea does sound good. It would have been an easier fix.
Rapper1
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#67205 10/19/2006 1:41 AM | Joined: Oct 2006 Posts: 31 Apprentice | | Apprentice Joined: Oct 2006 Posts: 31 | Well,I did as Bug suggested and dropped the torque tube,removed the u-joint,removed the yoke,pulled out the spacer sleeve. And while I had a great time,I accomplished nothing.I can push the speedometer gear so far forward that there is no way it can engage the drive gear so shiming from the rear doesn't seem to be an option.I guess I will make a call when I get further along on this project and either rebuild it or do as Rapper said and find another tranny.Thanks for your help,Chip | | |
#67206 10/19/2006 4:57 PM | Joined: Aug 2004 Posts: 13 Junior Member | | Junior Member Joined: Aug 2004 Posts: 13 | It sounds like the spacer is missing that goes between the rear main shaft bearing and the drive gear. I had a similar problem. Whoever worked on my trans last put the drive gear back on the wrong location on the main shaft. The Chevy Shop Manual shows all the parts and proper location. | | |
#67207 10/19/2006 9:53 PM | Joined: Jun 2000 Posts: 50 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2000 Posts: 50 | Chip - D449k is probably right. If the speedo drive gear spacer is missing there is nothing for the spacer sleeve to squeeze the drive gear against. Check out this manual for your truck, you can see the part #15 that must be missing. Hope this helps, Bug http://chevy.tocmp.com/1948_51truckshop/51ctsm0707a.htm
1951 Chevrolet 3100 AD Pickup
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#67208 10/19/2006 10:16 PM | Joined: Oct 2006 Posts: 31 Apprentice | | Apprentice Joined: Oct 2006 Posts: 31 | Bug,Thanks alot for the parts breakdown.I believe you and d449k are exactly right.I could remove the spacer sleeve out the rear of the transmission but the gear and the spacer washer had a larger od and would not come out that way.Looking at the picture,I think the washer[#15] is on the wrong side of the gear as ya'll said.I will have to deal with that later.I sure appreciate all the help. Chip | | |
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