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| | | | Joined: May 2010 Posts: 42 New Guy | | New Guy Joined: May 2010 Posts: 42 | From what I understand my '46 has straight-cut gears. Intellectually, I understand the difference between spur and helical gears, but in practice I'm less sure; so I have a couple of questions:
-Is it necessary to double clutch every time when shifting (up, down or whatever)?
-Clearly the spur gear is going to be more noisy, but how much grinding, loud gear noise is normal?
-Any advice on driving the old beauty?
Cheers~ | | | | | Joined: Nov 2005 Posts: 1,048 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 1,048 | If it is the same as my '41 they are straight cut and actually mesh gear to gear. Double clutching is always required for both up and down shifting. Once you have mastered the art of matching the engine speed to whatever it should be for the gear you are going into it is easy to shift even without the clutch.
And yes the straight cut gears wine all the time (except high gear) which is a straight through drive putting no load on the gears. There should be no grinding once you are in a gear and hopefully none during the shift, but then, shifting is an art and somewhat complicated by trying to keep the truck pointed in the correct direction without power steering.
As for advice, don't plan on doing anything quickly.
Good luck with your new ride
Kip | | | | | Joined: May 2010 Posts: 42 New Guy | | New Guy Joined: May 2010 Posts: 42 | Thanks Kip.
I'll keep practicing double clutching. I've never really noticed anyone doing it and so I'm just figuring it out, but the concept is straight forward enough. The tranny seems to be in good shape now, hopefully it stays that way once I get the hang of straight cut shifting. I can drive it just fine, just more grinding moving from 2nd to 3rd than I like to hear.
I try to never be in a rush and if I am, hopefully not in this truck! | | | | | Joined: Nov 2005 Posts: 1,048 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 1,048 | Going up....clutch in, shift into neutral, clutch out, allow the engine and front of transmission to slow to match the speed of the next higher gear, clutch in, shift up, clutch out.
Going down.....clutch in, shift into neutral, clutch out, speed up the engine and front of the transmission to match the speed of the next lower gear, clutch in, shift to the next lower gear, clutch out.
The easiest way to begin to not use the clutch is the first shift into neutral. Just match the engine speed to the road speed (not accelerating or decelerating) and slip the trans. into neutral. | | | | | Joined: Nov 2005 Posts: 1,554 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 1,554 | Does all this apply to the 3 speed also? Dave
1941 Chevy"First rebuild - complete!"Follow the story in the DITY1941 GMC resting peacefully 1946/1947 Chevy Street rod on s10 frame complete 1945 GMC panel truck in line for restoration 1941 Plymouth stock complete 1941 GMC COE in restoration processRead his Project Journal1941 Chevy Coe uncertain future resting now
| | | | | Joined: Jul 2005 Posts: 581 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 581 | Didn't the 3 speeds have synchronized gears? | | | | | Joined: Jan 2002 Posts: 237 Shop Shark | | Shop Shark Joined: Jan 2002 Posts: 237 | | | |
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