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#72025 01/22/2007 2:57 AM | Joined: Dec 2006 Posts: 7 New Guy | | New Guy Joined: Dec 2006 Posts: 7 | I am putting a 4 speed tranny in my 51 half ton. The 3 speed died. I got the correct u-joint from Tom Myers and cannot get the old speedo drive gear off the old u-joint. I tried tapping with a hammer and brass punch and warmed it with a torch and it still did not move. Any ideas? Richard | | |
#72026 01/22/2007 3:07 AM | Joined: Mar 2002 Posts: 553 Shop Shark | | Shop Shark Joined: Mar 2002 Posts: 553 | Maybe try putting the whole thing in the freezer 'till it's frozen then heat up just the gear portion with a propane torch while pry and/or wedge it off. | | |
#72027 01/22/2007 3:13 AM | Joined: Dec 2006 Posts: 7 New Guy | | New Guy Joined: Dec 2006 Posts: 7 | Thanks, I will try that tomorrow. I have packed old tractor sleeves with ice before to get them to turn loose and it worked when nothing else would. | | |
#72028 01/23/2007 2:46 AM | Joined: Mar 2005 Posts: 170 Member | | Member Joined: Mar 2005 Posts: 170 | I put a new U joint in my truck recently and had to wap the speedo gear. Its a ***** to get off. I used some heat, a bearing splitter and a hydraulic press. Got it off the old one and on the new one with no problem. | | |
#72029 01/23/2007 2:55 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | ndnchf,
When you put the new gear on the shaft, did you just drive it as far as it would go? Or, is there a measurement for the correct location?
Thanks, Tim | | |
#72030 01/23/2007 3:56 PM | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | I just replaced every moving part in the driveline of my '50, 3604. I replaced my old worn u-joint with a NOS 3689288 u-joint assembly and pressed off the gear the same as 'ndnchf'. Just be careful which bearing splitter you use because there is only a very small land on the back side of the gear and you don't want to support it on the teeth. I used a splitter out of a set from HF. The press I used is a small channel iron bench press my Pop made with an inverted 1-1/2 ton bottle jack. With the pressure pumped up full I heated the gear with a propane torch, not enough to even smoke the oil and it popped right off.
TC, the gear has a heavy chamfer that faces out or rearward toward the spline. The surface that faces the front or u-joint trunnion is flat and should be press up tight against the yoke.
Now mind you, this was a 3/4 ton and I don't know if the 1/2 ton is different.
Denny Graham Sandwich, IL
Denny G Sandwich, IL
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#72031 01/23/2007 4:35 PM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Denny,
Thanks for the information. The 1/2 ton truck and the larger truck 4-speeds should be the same for the speedo gear.
Tim | | |
#72032 01/23/2007 11:21 PM | Joined: Mar 2005 Posts: 170 Member | | Member Joined: Mar 2005 Posts: 170 | There is a shoulder on the U joint that the gear presses up against. | | |
#72033 01/24/2007 3:20 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Denny & ndnchf,
Thanks for the information. I am now not so scared to go in there to install the gear.
Tim | | |
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