Reproduction Parts for 1916-1964 Chevrolet Passenger Cars & 1918-1987 Chevrolet & GMC Trucks



Visit the new site at vcca.org

Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Jun 2007
Posts: 234
Likes: 4
Backyard Mechanic
OP Offline
Backyard Mechanic
Joined: Jun 2007
Posts: 234
Likes: 4
Mark Gregush, with a 1924 Superior, encouraged me to make a post on my experiences of changing gears on my 1922 490. See his thread on the 1912-1928 forum.

All 490 models and the 1923-1924-Superior models have the same cone clutch, and practically the same transmission. On the 1912-1928 or 1916-1922 forums you can find a number of threads on the clutch and transmission. For instance, search for “cone clutch”. But I have not seen many posts on experiences of changing gears on these cars.

Therefore I decided to open a new thread, on both these forums, hoping that it will inspire others to make comments on their experiences. I am really interested, because I am not sure if I have got it all right.

I have owned my 490 ten years, during these years I have been driving 12 000 kilometers (7 600 miles).

If you don’t know the construction or function of the cone clutch and the transmission you can take a look in the “Instructions for the operation and care of Chevrolet Motor cars, Four Ninety and Superior Models”, Issued July 1 1923, which you can find here , pages 43-46. In the instructions for 1924 Superior, which you can find here , you can find them on pages 44-47.

I usually start on the first gear, and shift to second gear at a very low speed, one or two mph, and the motor still idling or with just a little revving. So usually I change after just a few meters or feet. I make the shift passing the neutral quite fast, or say resolute, after releasing the clutch. Why? Because as soon as the gear shifting lever reaches the neutral position, the main shaft going into the transmission (ingoing shaft), the counter shaft and the idler shaft retards and stops very quickly. Why? I think that the main reason is that the main shaft gear, the three gears on the counter shaft and the two gears on the idler shaft works in a very heavy oil, either you use the often recommended 600W Steam Cylinder Oil or the similar modern 250W straight transmission oil which I use. VERY heavy just as you have started the car, especially if it is a little chilly. Another reason is that as the clutch is released, the clutch yoke is pressed against of the rear part of the clutch hub. As the cone is not very heavy, the main, counter and idler shafts can retard and stop quite quickly. You can easily check how quick the cone and the ingoing shaft stops if you remove the floor, start the motor and press and let up the clutch pedal.

If the ingoing, counter and idler shafts has stopped and the car is still rolling slowly, I just let the clutch pedal up, immediately press it down and make a resolute shift from neutral to second gear. The idling motor mostly makes the ingoing and counter shafts revolve enough to make the “second speed counter shaft gear” match the speed on the “high and second speed sliding gear” on the main shaft going out from the transmission (outgoing shaft).

If the ingoing, counter and idler shafts has stopped and the car is rolling faster, it is necessary to rev up the motor before shifting from neutral to second gear. This situation happens to me every time I leave our house, because the drive is a quite steep slope. I drive down the slope on the first gear, letting the motor make the braking job. When I have left the slope the speed is maybe five mph or more. I release the clutch, shift from first gear to neutral, let up the clutch pedal, rev the motor quite a lot, immediately release the clutch and make a resolute shift from neutral to second gear.

I use to shift from second to third gear at 15-20 mph. After releasing the clutch, I move the lever from second to third position without a paus in the neutral position, or with just a very very short paus. Why such a hurry? Because if I make a longer paus, of the same length that I do on my 1931 Opel, my 1964 Volvo 121, and that I did on the 1925 Superior with the new flat clutch that I owned for two years, the ingoing, counter and idler shafts retards and stops, as described above. This happens to me now and then, and then I have to let the clutch pedal up, rev up the motor, immediately press the pedal down and make a resolute shift to the third gear.

So I do not quite agree with the advice in the “Instructions…” that I mentioned above. There you can read this: “Be deliberate: It is well to pause a moment or two after disengaging the gears before moving into the next speed. The fundamental requirements in every case are that the gears to be meshed shall be revolving at as nearly the same speed as possible (this is of course correct). By waiting a moment, time is given for this to take place.”

Can it be that the reason my experiences differ from the “Instructions…” is that the gears in my transmission are excessively worn? Or can there be other reasons?




Per-Åke Larsson
Filling Station - Chevrolet & GMC Reproduction Parts


Filling Station


Joined: Nov 2008
Posts: 1,513
ChatMaster - 1,500
Offline
ChatMaster - 1,500
Joined: Nov 2008
Posts: 1,513
Thanks for the information very interesting.

Joined: Jul 2016
Posts: 39
Shade Tree Mechanic
Offline
Shade Tree Mechanic
Joined: Jul 2016
Posts: 39
This is very interesting. My 1915 Dodge Bro has a cone clutch and I have always had trouble shifting. This may help me

Joined: Dec 2014
Posts: 145
Shade Tree Mechanic
Offline
Shade Tree Mechanic
Joined: Dec 2014
Posts: 145
Thank you for posting. I am going to copy it and give to the car owner.

Joined: Jan 2002
Posts: 1,623
ChatMaster - 1,500
Offline
ChatMaster - 1,500
Joined: Jan 2002
Posts: 1,623
I have very limited experience driving my 1914 Baby Grand so far, only a handful of miles, since it only recently has been returned to driveable condition. I had at least a few hundred miles of driving my 1916 490. But I have many thousands of miles of driving other early cars, from a 1907 Highwheeler, a 1908 Buick, on up into the 1920s and '30s. Unfortunately, these were all different transmission/clutch arrangements, not leather and cone.

In both early Chevys, I have this very same problem - when trying to up-shift, as soon as the clutch is depressed, the transmission internals very quickly slow down and grinding results, in spite of revving the engine, double clutching, or other efforts. It is somewhat worse from 1st to 2nd than it is from 2nd to 3rd. To downshift back to 2nd from 3rd is impossible (so far).

I agree with your analysis of what is happening, and I will watch this string to see if anyone has ideas that help the problem. As I gain more experience driving my 1914, if I learn some tricks that make shifting better, I will certainly share. (I think I should probably get the brakes working a little more effectively before I do much more driving, though!)


Chevy Guru
Joined: Jul 2014
Posts: 53
Shade Tree Mechanic
Offline
Shade Tree Mechanic
Joined: Jul 2014
Posts: 53
I have been driving my 23 roadster with cone clutch for a couple of years now.
I have sorted out what works, but must say that now and again the car refuses second to third and the only thing to do is stop and begin afresh!
But most of the time I do not over rev, and I do not double de clutch.
I move from first to second at about 5mph, I have learnt that even slightly over revving makes the gears grind, but the right sort of revs allows the gear to be slipped in quietly.
Likewise into top, learn the correct rev range and the gear will go in quietly just by listening to the engine and not double de clutching.
Third to second is a whole different ball game, and I haven't totally mastered it every time, but the majority of time: I rev the engine but not too high, and depress the clutch only very slightly and the gear goes in quietly. If I overvrev and/or press the clutch in too far it will not go in!

Joined: Jun 2007
Posts: 234
Likes: 4
Backyard Mechanic
OP Offline
Backyard Mechanic
Joined: Jun 2007
Posts: 234
Likes: 4
Hi Andys29, verng, Mark G, ChevyGuru and 23Chevvy: I am really looking forward to hear about your coming experiences!

23Chevvy: At what speed do you usually shift from second to third?

23Chevvy: I find your experience, “depress the clutch only very slightly and the gear goes in quietly” when downshifting very interesting! I think I have the same experience, but I have not noticed it systematically. I am quite sure I have noticed the same also as I shift from first to second, and I am going to check more systematically on coming tours. My preliminary guess is that your experience supports my analysis in my first post: As soon as clutch is released, do not wait too long before you fulfill the change.

23Chevvy: You state that “I haven’t mastered it every time”. Same for me, of course. I am satisfied if I make two of three shifts without annoying grindings, or nine of ten shifts without or with only minor annoying grindings.

I recommend that you also follow posts on this topic on the 1916-1922 (only 490) Forum There you will find an interesting post from Solan, that I have commented. In that post I hav also included a couple of pictures of the inner parts of my transmission.


Per-Åke Larsson

Link Copied to Clipboard
 

Notice: Any comments posted herein do not necessarily reflect the official position of the VCCA.

Powered by UBB.threads™ PHP Forum Software 7.7.5