Track Day.... driveshaft slip out?
08-04-2010, 04:11 PM
#17
Race Director
since you 928 ran fine until the clutch was worked on my thoughts are
1: loose front clamp
2: broken input shaft
3: broken TT
none of which are easy fixes...unless the clamp didn't damage the splines.....a loose rear clamp is also possible, but you didn't touch it....so its less likely....
Since your engine isn't a torque monster I think a broken tranny or TT is unlikely..but it does happen...
1: loose front clamp
2: broken input shaft
3: broken TT
none of which are easy fixes...unless the clamp didn't damage the splines.....a loose rear clamp is also possible, but you didn't touch it....so its less likely....
Since your engine isn't a torque monster I think a broken tranny or TT is unlikely..but it does happen...
08-04-2010, 04:50 PM
#18
Rennlist Member
spin the engine, see if the torque tube rotates through the peak holes. common,we are waiting!!!!! 
It will and its the 5th gear, I betcha!
Brian. a beer says its the 5th gear input shaft!
It will and its the 5th gear, I betcha!
Brian. a beer says its the 5th gear input shaft!
08-04-2010, 08:45 PM
#19
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Let me get the car back home, figure out how to get up my driveway on my lift.
Hey, if it's 5th gear, and I don't use 5th...
Still fix the gear?
I do know we tried to start it in gear... Nothing.
08-04-2010, 09:14 PM
#20
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Although called 5 th gear it is really the input shaft but is hardened steel and somewhat brittle. The drive shaft fits inside and has MATCHING SPLINES the input shaft has tree slots dividing it into three ears. That allows the clamp to compress it slightly so the splines are tight. However and number of things inclkuding hanging a trans onl;y by the shaft while you undo the torque tube to trans bolts can break of one ear. Then under load it spins off the spines. The old very brown 1980 with 200 rwhp managed to break one tab. It never spun but made a clunk clunk as you got on and off the gas. Mark Anderson donated a good used trans (it does click in first) the common reverse idler issue but who uses first ? Thanks again !
Thanks again !
08-04-2010, 10:13 PM
#22
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5th gear means the entire gear and output shaft of the transmission, unfortunately, they are one and the same. if that breaks, you dont have any drive, let alone just 5th gear. 
you could do this. start it again, and then listen as you put the clutch in. if you put the clutch in with it in neutral, and you hear things slow and stop spinning. (kind of a faint sound) that might be the torque tube slowing down and stopping if it is connected, which I imagine it will be. this will mean its broken at the rear which means 5th gear is toast.
you could do this. start it again, and then listen as you put the clutch in. if you put the clutch in with it in neutral, and you hear things slow and stop spinning. (kind of a faint sound) that might be the torque tube slowing down and stopping if it is connected, which I imagine it will be. this will mean its broken at the rear which means 5th gear is toast.
08-04-2010, 11:19 PM
#23
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Although called 5 th gear it is really the input shaft but is hardened steel and somewhat brittle. The drive shaft fits inside and has MATCHING SPLINES the input shaft has tree slots dividing it into three ears. That allows the clamp to compress it slightly so the splines are tight. However and number of things inclkuding hanging a trans onl;y by the shaft while you undo the torque tube to trans bolts can break of one ear. Then under load it spins off the spines. The old very brown 1980 with 200 rwhp managed to break one tab. It never spun but made a clunk clunk as you got on and off the gas. Mark Anderson donated a good used trans (it does click in first) the common reverse idler issue but who uses first ? Thanks again !
Thanks again !Everything seemed great after the clutch install. Drove it a little in Pebble Beach (home).
Just barely got to 3rd gear and it quit.
Is it normal to no sound of gears crunching or something grinding??
NOTE** We did see metal shaving in the back peak hole.
Oh boy, this doesn't sound good
08-04-2010, 11:55 PM
#25
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ewwwww! that brings back bad memories!
Yes, it can be silent. the only noise I heard was a slight clicking noise of the two pieces of shafts kind of hitting each other. if it is totally silent, that is kind of strange. Like I said, just turn over the engine, put the clutch in and see if you hear the slow down of the torque tube . should be a quick slow down sound.
Yes, it can be silent. the only noise I heard was a slight clicking noise of the two pieces of shafts kind of hitting each other. if it is totally silent, that is kind of strange. Like I said, just turn over the engine, put the clutch in and see if you hear the slow down of the torque tube . should be a quick slow down sound.
08-05-2010, 02:17 AM
#27
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just replace that 5th gear and rebuild the transmission, or better yet, bite the bullet and get an 85 or S4 trannie. that makes racing the 928 a dream!
you have the trannie, it was working, but how were the synchros? you might just be better off doing synchros and a new 5th gear. I dont know how expensive 5th gears are, but that might be an option.
I would be leaning toward a 85 gear box if I were you.
you have the trannie, it was working, but how were the synchros? you might just be better off doing synchros and a new 5th gear. I dont know how expensive 5th gears are, but that might be an option.
I would be leaning toward a 85 gear box if I were you.
08-05-2010, 02:27 AM
#28
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just replace that 5th gear and rebuild the transmission, or better yet, bite the bullet and get an 85 or S4 trannie. that makes racing the 928 a dream!
you have the trannie, it was working, but how were the synchros? you might just be better off doing synchros and a new 5th gear. I dont know how expensive 5th gears are, but that might be an option.
I would be leaning toward a 85 gear box if I were you.
you have the trannie, it was working, but how were the synchros? you might just be better off doing synchros and a new 5th gear. I dont know how expensive 5th gears are, but that might be an option.
I would be leaning toward a 85 gear box if I were you.
Are you saying these trannies are interchangeable?
Plug and play?
08-05-2010, 02:35 AM
#29
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