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TR4/4A TR4A IRS Issues and Smashed Thumb Question
- Thread starter KVH
- Start date
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luke44
Jedi Warrior
Offline
Sorry Joel - doctor or not, you can't top first hand (er finger) experience.
Back in my racing days I smashed a finger nail between the Spitfire transmission and its mount. It came down on my finger with the added pressure and leverage of the 2 motor mounts wound up when the pry bar slipped. It was truly ugly purple and incredible pain, so I know exactly what KVH means.
The only pain worse was about an hour later with the attempt to use a hot paper clip to puncture and relive the pressure. That was <span style="font-style: italic"><span style="font-weight: bold">far </span></span>worse than the original injury. And no relief - the finger nail cauterized over. I still get shivers when I recall the pain from that paper clip....
Back in my racing days I smashed a finger nail between the Spitfire transmission and its mount. It came down on my finger with the added pressure and leverage of the 2 motor mounts wound up when the pry bar slipped. It was truly ugly purple and incredible pain, so I know exactly what KVH means.
The only pain worse was about an hour later with the attempt to use a hot paper clip to puncture and relive the pressure. That was <span style="font-style: italic"><span style="font-weight: bold">far </span></span>worse than the original injury. And no relief - the finger nail cauterized over. I still get shivers when I recall the pain from that paper clip....
hondo402000
Darth Vader
Offline
well I shot a nail in my forearm over the 4th with a nail guy but since I was working on putting a roof over my deck and not on my TR6 I figured it wasnt worth mentioning in the forum, but all is well now and my arm did turn black and blue up to my elbow and no nerve damage, but the bills are just now comming in
Hondo
Hondo
TR3driver
Great Pumpkin - R.I.P
Offline
That doesn't sound like any fun at all, Hondo! Makes me glad the flooring I'm installing is nailless!
FWIW, I've always used a hot needle rather than a paperclip or drill, for piercing fingernails. Worked fine for me, can be repeated if necessary (I once wound up with 4 different holes in a thumbnail). But I did eventually learn to think about what would happen if the wrench slipped (or the bolt broke), so I haven't needed it in a long time
To get back to the original question, a Limited Slip Differential works by limiting the differential action, so that if one wheel lacks traction, more of the torque is applied to the other wheel. It sounds like what you have is a "viscous" limited slip differential, meaning the limiter is a viscous clutch that wants to make both output shafts turn together. There are other types of course.
I would guess that you had the driveshaft locked (by having the transmission in gear). With the input locked, you can only turn an output flange by forcing the other flange to turn the opposite direction, against the viscous coupling.
If the input was not locked, then turning either output flange should cause the other flange to turn the same direction, and the input to turn much faster.
Another possibility is that the pinion preload is a little on the high side. I have no idea what the spec is for the Nissan diff, but it is supposed to take (roughly) 1-2 ftlb to turn a Triumph diff against the preload, measured at the pinion, which translates to roughly 4-8 ftlb at the output flanges.
FWIW, I've always used a hot needle rather than a paperclip or drill, for piercing fingernails. Worked fine for me, can be repeated if necessary (I once wound up with 4 different holes in a thumbnail). But I did eventually learn to think about what would happen if the wrench slipped (or the bolt broke), so I haven't needed it in a long time
To get back to the original question, a Limited Slip Differential works by limiting the differential action, so that if one wheel lacks traction, more of the torque is applied to the other wheel. It sounds like what you have is a "viscous" limited slip differential, meaning the limiter is a viscous clutch that wants to make both output shafts turn together. There are other types of course.
I would guess that you had the driveshaft locked (by having the transmission in gear). With the input locked, you can only turn an output flange by forcing the other flange to turn the opposite direction, against the viscous coupling.
If the input was not locked, then turning either output flange should cause the other flange to turn the same direction, and the input to turn much faster.
Another possibility is that the pinion preload is a little on the high side. I have no idea what the spec is for the Nissan diff, but it is supposed to take (roughly) 1-2 ftlb to turn a Triumph diff against the preload, measured at the pinion, which translates to roughly 4-8 ftlb at the output flanges.