Transmission lock out

pmlmbigpondcom

G'day All

This is probably a question for Geoff in NZ, but.....

Regarding the lock out which prevents gears being engaged till clutch is depressed, how important is this ?

Do I need to hook it all up ---- or will considerate use of the clutch and gears be ok ?

Looking forward to comments

Thanks

Phil

Australia

Uncle Josh

Just my opinion, but is seems this appeared about the time as the electric hand, which, if not adjusted properly, could try to shift gears without the clutch being fully released.  Even with this interlock, my 36 Terraplane takes a little practice to avoid clashing gears.  Shift not too fast, but not too slow.  What think ye, Mr Battle?

Park_W

The Electric Hand had its own clutch interlock switch with a turnbuckle adjustment, so it didn't rely on the transmission shift rail locks.  Josh, you're dead on when it comes to shifting these non-synchronized trannies.  As we old-timers learned, there's a sort of rhythm that one develops with a little practice.  Of course we're talking upshifts here . . . downshifting these critters takes a properly executed double-clutch maneuver.  Better to just let'er stay in third 'til you're stopped!

Jon B

Unk:  quick shift from first to second; show shift from second to third.  Still, we haven't answered Phil's question: is the mechanical lockout needed at all?

Geoff

Theoretically, it is not needed.  My '39 CC8 did not have them, and it never jumped out of gear. The purpose of them is to ensure that you have the clutch fully disengaged before changing gear.   The trick in changing gears is to do it fast.  I have seen many techniques, most of them resulting in clashing gears.  Too much of this results in the  dog teeth getting tapered, and this leads to jumping out of gear, and this is where the locks are benificial.   the only Owner's instruction manual which actually tells you how to change gear is the '34 version which tells you to do it fast.  This not related to car or engine speed, but the speed at which you shift the gear lever!  I tried to tell one owner that  the needed to shift gear faster, so he speeded up  more than usual before attempting to change, then did a big long pause  in between the shift, of course resulting in a great clash.  "Didn't work", he said!

Frankvintagefullflowcom

Un-sychronized transmissions must be shifted utilizing the "double-clutching" method both up and down. I learned to drive in my Dad's '42 C-6 which, of course, was synchronized (2-3) at some earlier point in its life but certainly wasn't by the time he got it. It becomes a fun little game to hone your anti-clashing skills while driving these old cars and came in real handy during my "career" as a truck driver. There are shifts you just can't make without it. If done correctly, you should never hear a gear grind.
Out of habit, I double clutch all manual transmissions, synchronized or not.
True, the lock-out device isn't a requirement and can be in the way at times. Our '47 had one that had been disabled when we got it (common, I'm sure) but I resurrected it in the process of rebuilding the drive train. My recollection is that well worn transmissions tend to drop out of gear under certain operating conditions, especially out of second on column shift vehicles (danged gravity!). Once they begin to pop out under load, there's no turning back.
F

35 Terraplane

I've been able to upshift my 35 Tplane as Geoff said by moving the floor shifter quickly without grinding the gears. Not so much downshifting. I've driven many standards but I'm sure all with syncro's. I'm curious about the double clutching technique. Can you give a blow by blow of what happens.
Thanks Tom

Uncle Josh

Geoff, your story for some reason reminded me of the guy whose battery was dead, so this lady offered to give him a push.  He told her it was an automatic and would need to be going 35 mph before it would turn the engine.  So he gets in and waits..quite a while..and then he looks back and sees her coming at him at 35 mph

ken1962

G"day

In my 36Terraplane I need to double clutch down from 3 to 2 (too hard from 2 to 1)

I had to learn how to do it with my Dad showing me how when I first got the car.

Find a straight piece of road that is not used (important that there is no chance or a person or car appearing ahead as you aren't looking out the window - maybe have some one as passenger to watch out in case)

Change thru the gears till in 3rd travelling at not more than approx. 22 mph

Depress the clutch

move into neutral

rev the engine in a short sharp pip of the foot

(now the tricky bit)

whilst the engine is revving back down depress the clutch and place it into 2nd gear

The engine has to be revving at a higher spin than the gear box and you catch the engine on its downward rev

It took me about 3 hours driving up and down the road practicing the move

The revving down of the engine and the clutch and gear movement have to all seamless and you need to not think about it to be successful

Its really important that you have no cars around as you need total focus on the movement not what's out the window ahead. If you can break it down into steps then practice going from 3 to 2  and then and back for an hour or too till it can become automatic. The tip I found was that first trying, really rev the engine hard then lift your foot from the gas pedal and the engine revving down should give you enough time to depress the clutch and place it into 2. Its a great feeling to achieve this double clutch rather than crunch the gears

Once you can double clutch down, on another day practice double clutch up

I find it almost impossible to double clutch 2 to 1 as the engine revs need to be too high for me. I just leave it in 2nd till I come to a stop, then change it into 1st to move off

Whilst on the quite road do some emergency stops. I was practicing in a new estate using a 2 lane road driving in the middle and found the car would brake like a boat throwing the car hard left. The front brakes needed adjustment. It was also good to see how the car behaved stopping hard at 25,35,45 miles per hour

at a mark on the road, rather than the arse of the car ahead

Good luck 

 

35 Terraplane

Ken, thanks for the lesson. It's winter here and the car is put up now. In the spring I'm looking forward to mastering the double clutch techique.
Tom

Geoff

Also remember that the technique is different  than used in a conventional "crash box".   hen changing up on say, and Essex or Hudson Super  Six  you do have to pause in neutral for the gears to stop spinning.  this is because of the inertia of the heavy mass of the gear train.  In  the later gearboxes form '32-'40 there is little inertia, as the  countershaft does not have a big heavy cluster  of gears on it.  Plus the fact that the second gear is in constant mesh, and helical gears, the countershaft stops spinning almost immediately you put your foot on the clutch, hence the slick-shift method of just flicking the gear lever up from low to second, and just very slightly slower going into top gear.  You must do this immediately upon depressing the clutch.   Once you get the hang of it you will be amazed at how fast you can shift gear noiselessly.   Again, changing down form top to second the owners manual says to  move the gear lever as fast possible, immediately after depressing the clutch.   All you will hear is a slight click as the drive dogs engage.  however, I dislike this method and  prefer to rev the motor in neutral with the clutch out before depressing the pedal  and  engaging second  straight away.   As the old adage says - "Practice makes perfect"... Happy crunching!  If I come to Colorado Springs I will be glad to give a free demonstration.  

Geoff 

pmlmbigpondcom

Thanks All

I probably will reinstall the lock out mechanism, was just curious about it

Phil