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-   -   Changing into 1st/reverse while fully stopped (https://6066gmcclub.com/showthread.php?t=49617)

Jmclendon September 27th, 2016 09:12 AM

Changing into 1st/reverse while fully stopped
 
Hello all,
It's highly likely that I'm going to sound like an idiot with this. But, for the life of me unless I disengage the clutch for a 6 count or so I can't find a way to consistently change into 1st without getting the dreaded grinding noise.

I've tried the following (all from a complete stop)

Clutch in, shift into second, back to neutral, clutch out, clutch in, shift into first (grinds)

Clutch in, shift into second, take clutch out a touch, clutch in, shift into neutral, clutch out, clutch in, shift into first (grinds)

With each I've tried no throttle and blipping the throttle as I come through neutral. Neither works.

This is the first vehicle that I've driven that wasn't fully synchronized. So, I'm sure it's something dumb that I'm doing. But, for the life of me I can't work out what it is.

Any help would be greatly appreciated!

Oh, btw, it's a 3 speed column shift.

sclor September 27th, 2016 02:01 PM

Re: Changing into 1st/reverse while fully stopped
 
Mc:
Seems like when you "clutch out" in between shifts you get the gears in the tranny spinning again, thus the grind when you go for first. I would keep the clutch in the whole time. If you want to go into second, then back to first, I would keep the clutch in the whole time. Otherwise you need to wait a bit for the tranny gears to stop spinning before you try to go into first.

Only other check is to make sure your clutch is releasing all the way. How much free play does it have when coming off the floor before the truck starts to move while in gear?

Hope that helps.
Regards,
Steve
New Orleans

FetchMeAPepsi September 27th, 2016 02:28 PM

Re: Changing into 1st/reverse while fully stopped
 
IIRC 1st gear isn't synchro'd in 1961. You'll have to wait till you stop to keep from grinding. These boxes aren't made for speed downshifting :)

On my 62 I clutch in, shift into 2nd, then pull it into 1st, then clutch out to go.

David R Leifheit September 27th, 2016 06:01 PM

Re: Changing into 1st/reverse while fully stopped
 
Quote:

Originally Posted by FetchMeAPepsi (Post 63788)
IIRC 1st gear isn't synchro'd in 1961. You'll have to wait till you stop to keep from grinding. These boxes aren't made for speed downshifting :)

On my 62 I clutch in, shift into 2nd, then pull it into 1st, then clutch out to go.

You would be correct. The "stock" 3 speed is non-synchro first gear. You *might* get it into gear without grinding while moving, but that would be unusual. There are at least 2 three speed transmissions I know of, the more common non-synchro and there is one which does have synchros on first.
I've replaced all of mine with top-loader 4s so I don't have this problem :) as no one I know tries to shift into granny while rolling.

It just takes some getting used to all the quirks of the vehicle. Non-synchro first wasn't ever the big problem for me, I had issues with third wearing out so if I let up on the throttle it would pop out of gear. Had to drive with my hand on the shifter to keep it in third. Which is why I ended up replacing the one in my first truck. Then just swapped out in the other trucks which had 3 speeds.

David R Leifheit September 27th, 2016 06:03 PM

Re: Changing into 1st/reverse while fully stopped
 
Quote:

Originally Posted by Jmclendon (Post 63784)
Hello all,
It's highly likely that I'm going to sound like an idiot with this. But, for the life of me unless I disengage the clutch for a 6 count or so I can't find a way to consistently change into 1st without getting the dreaded grinding noise.

I've tried the following (all from a complete stop)

If it grinds when at a complete stop, with clutch in, you may not be disengaging all the way. You may need to adjust the clutch.

jimjaz September 28th, 2016 02:41 AM

Re: Changing into 1st/reverse while fully stopped
 
I agree with David and Steve on this one-
If you are stopped and not rolling, then pulling the column shifter to engage 1st gear you should not be grinding any gears if your clutch is adjusted properly. I am not familiar with 61's with a column shift if you have the dual master cylinder making your clutch hydraulic, but whether it is hydraulic or mechanical, you can adjust the clutch so that it fully disengages from the flywheel. If you are not fully disengaged, then your clutch plate will be rubbing (some) and this will cause your transmission to spin. This is what I think is going on. When you are completely stopped, transmission in neutral, and you step on the clutch, how far does the pedal travel before you feel some resistance other than the return spring that is up underneath the dash? If it is more than a couple of inches, adjust your clutch rod nut clockwise (like turning a screw clockwise) there should be two nuts so you will need to break these free of each other and adjust the nut that rests up against the clutch release fork clockwise a few full turns, then try it again. Once you get it set where you think you want it, then you can jam the rear nut up against the front nut to keep it locked in and stationary. Just be careful when doing this (you are not going to hurt anything unless you get it adjusted and then find out that you can't climb a hill anymore because the clutch is slipping on the flywheel- your engine RPM's are cranking, but you are slowing down) - this will cause you to burn up your clutch over time and possibly warp your flywheel a bit, sort of like disc brake rotors that are not true so when you brake the vehicle creates a shimmy because the rotors up front are warped.

Since your transmission is not a 1st gear synchro, all this really means is that you can't pull your tree lever into 1st gear if you are rolling at all. If this is all it is, then don't go chasing the clutch adjustment.
Let us know what you find out.
Jim

Jmclendon September 28th, 2016 03:02 AM

Re: Changing into 1st/reverse while fully stopped
 
Quote:

I am not familiar with 61's with a column shift if you have the dual master cylinder making your clutch hydraulic
The brake and clutch master cylinder are a single unit. For safety, at some point I'd like to swap the brakes over to a dual. But, that's a bit down the track.....

Quote:

If you are stopped and not rolling, then pulling the column shifter to engage 1st gear you should not be grinding any gears if your clutch is adjusted properly.
Are you saying that if the clutch is adjusted properly that I shouldn't have to clutch-in, shift to second, shift to first at all? Or would that still be required since 1st isn't synchronized?

FetchMeAPepsi September 28th, 2016 03:10 AM

Re: Changing into 1st/reverse while fully stopped
 
Quote:

Originally Posted by Jmclendon (Post 63801)
Are you saying that if the clutch is adjusted properly that I shouldn't have to clutch-in, shift to second, shift to first at all? Or would that still be required since 1st isn't synchronized?



Since first isn't synchronized you don't have to shift from 2nd to first, but you will see grinding if you don't and you just came off moving. It takes a moment or two for the tranny to spin down. If you've been at a dead stop for a minute you can shift into first and go. If you haven't, a slide into second will sync things up then you can go into 1st without incident.

Also, if you shift into neutral and release the clutch you'll see grinding because that'll start the spinning up again.

Jmclendon September 28th, 2016 05:14 AM

Re: Changing into 1st/reverse while fully stopped
 
From memory there's not too much free play in the clutch. But, I'll measure it up this afternoon when I get home.

I'll see how I go with keeping it in neutral during the change to second and first. If that doesn't work then I'll have a go at adjusting the clutch.

Hopefully this will be the step on the path to using as a daily driver.

Jmclendon September 28th, 2016 09:34 AM

Re: Changing into 1st/reverse while fully stopped
 
I've got a touch over an inch of free play in the clutch.

Having said that, I took him out for a spin this afternoon and it looks like disengaging the clutch, shifting into second and then into first (or reverse) is working like a dream. I'm still coming to a complete stop (and have every intention of doing so). But, do we think it would be safe to say that it was just a case of me not knowing how to drive?


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