Author Topic: 1930 T6 handchange gate 4 speed (Read 3356 times)

alan reid · « **on:** 23 Feb 2021 at 13:57 »

Hi, more problems My 3speed gearbox is not all that it should be, however i have a 4 speed gearbox i am going to use.
The problem is I will need a a speed gate on the petrol tank.
I don't think I will ever find one, so I will make one.
If you have a 4 speed T6 or S6 could you let me know the Measurements of the cut outs on the gate.

With this info I can make a start.
Regards Alan

Typo fixed in heading to help search results - Dave, 10Oct2021

douglas1947 · « **Reply #1 on:** 26 Feb 2021 at 12:32 »

Hi Alan,

I have a S6, fitted with a 4-speed gearbox. If you want, I can make a photo of the gate.

Michael

Doug · « **Reply #2 on:** 26 Feb 2021 at 13:53 »

I think I am in the same predicament, I do not recall seeing a gate with my 4-speed Greyhound basket case. A paper rubbing of the gate face and flatbed scan would really be helpful.

-Doug

alan reid · « **Reply #3 on:** 26 Feb 2021 at 14:47 »

Thanks Michael,
a photograph of the 4 speed gate would be a bog help.

Regards Alan

alan reid · « **Reply #4 on:** 26 Feb 2021 at 14:51 »

Hi Doug,
Yes a rubbing of the 4 speed gate would also be a big help.

Alan

douglas1947 · « **Reply #5 on:** 27 Feb 2021 at 15:15 »

Hi Alan + Doug,

I have made 2 photos of the gate, but the quality is not so good; a bit dark in the room.

Gear lever is in Neutral, 1rst is on top on this gearbox.

If you want I can make a rough drawing with mm mesures of the ate slots and scan it?

Michael

alan reid · « **Reply #6 on:** 27 Feb 2021 at 16:42 »

Thanks Michael,
The pics are a big help as I can see the correct shape.
If you could also let me know the approx measurements that would be fantastic.

Alan

Tazmantic · « **Reply #7 on:** 27 Feb 2021 at 19:00 »

Ok guys I’m not usually much help but maybe this time, I recently bought a tank and it had a 4 position gate on it. As my 250s only have a 3 speed box I may well be happy to part with it

[Image aspect ratio fixed. 28Feb21 -Doug, Admin]

alan reid · « **Reply #8 on:** 27 Feb 2021 at 20:23 »

Hi there,
Yes how much do you want for it?
Looks just the job.
Regards Alan Reid.

Doug · « **Reply #9 on:** 28 Feb 2021 at 05:38 »

Alan, Tazmatic,

Be advised there was also a 4-speed hand change gate used on the more bulbous petrol tanks of the heavywheight 1934-38 models. Not certain, but think the curve would be different where it mates to the tank for the T6, S5, S6. The gate pattern and dimensions might well be the same, given it is essentially the same 4-speed gearbox used (insofar as shifting goes) on the 1932 S6 models through the Aero models. So long as the gate is the same distance from the pivot point on the S6/T6 as the later gate; else the pattern may need to be stretched/shrunk.

Some examples of the later gate:

You have to beware there is a variation of these with pattern reversed (1st gear forward) used on the 1934-35 ohv models!

-Doug

douglas1947 · « **Reply #10 on:** 28 Feb 2021 at 16:43 »

Hi all,

I think Dougs answer is right. It looks like the gate shown on the photos of the late Douglas has an other shape to the tank.
I have tried to notice all measures of the gear gate on a paper today (my S6 is not standing at my home) to make a drawing, but unfortunately there are missing a few mesures. So I have to do it tomorrow again. But I can tell you, the S6 gate is on each end 35mm wide.

Michael

alan reid · « **Reply #11 on:** 28 Feb 2021 at 17:07 »

Hi chaps,
Looking at the 3 speed gate the complete length of the slot is approx 100mm.
Does the 4 speed have a longer slot?

Alan

Tazmantic · « **Reply #12 on:** 28 Feb 2021 at 18:29 »

I’m struggling at the moment to Add more pics as my laptop has failed but it is from what I think is an aero 600 tank

Doug · « **Reply #13 on:** 28 Feb 2021 at 18:33 »

I am missing one for my 1936 Aero project. I do have one from a second Aero I could copy, but there are an awkward shape to fabricate!

-Doug

alan reid · « **Reply #14 on:** 28 Feb 2021 at 18:48 »

Hi Tazmantic,
From the pic of your 4 speed gate, it looks like with a bit of work it could be made to fit a T6.
A nip & tuck!

Alan

douglas1947 · « **Reply #15 on:** 01 Mar 2021 at 14:12 »

I have finished the drawing this morning. The gate is original casted, you can see on the cut A-A The border of the gate is 6mm, the middle with the slots only 3mm.
Please ask for further information and I will try to help.

Michael

Doug · « **Reply #16 on:** 01 Mar 2021 at 16:08 »

Michael, Thanks for posting that. -Doug

alan reid · « **Reply #17 on:** 01 Mar 2021 at 17:27 »

Hi Michael,
Many thanks for your effort you took with the drawing, I should be able to sort it out now.

The 4 speed gearbox I am about to fit has no numbers on the outer case?
And the 1931 parts book only lists a 3 speed gearbox.
Do you know what Douglas parts book lists the first 4 speed box?

Alan

Tazmantic · « **Reply #18 on:** 01 Mar 2021 at 19:14 »

Hi sorry for the delay laptop now running through TV as screen broken

My gate seems to have the same dimensions but the curve is bigger, Ive attached a couple of pics........I hope

Image orientation corrected and enlarged - Dave, 03Mar2021

douglas1947 · « **Reply #19 on:** 02 Mar 2021 at 05:10 »

Hi Alan,

my gearbox is stamped on top GB 702.
I think there was only one type of 4-speed boxes for the heavy weight Douglas?

It may be possible to make the later gate for Aero type petrol tank fit to the mild curve of the S6 tank shape?

Michael

Doug · « **Reply #20 on:** 02 Mar 2021 at 06:10 »

GB is the gearbox code for the E32/H32 4-speed option. I believe 1932 was the first year the S6 and derivatives had the option for a 4-speed. The only spares list that I have seen for the S6 models is a February 1931 issue, predating that so no 4-speed parts listed. While fundamentally all the subsequent heavyweight side valve 4-speed gearboxes were the same, there were detail improvements. One of the first was the change to constant mesh kick start gears by 1934 (probably nothing much happened in 1933!) Then there was a change from stub to involute tooth form around 1935. Possibly other minor changes, but those are the two big ones. The first parts list that I am aware of listing the 4-speed components (1936) dates from the Aero era.

I think by the time you sand the curve flatter on the back of a Aero era hand change quadrant, you will have removed most of the mounting ears. Also one would need to check that the mounting holes are the same distance apart and the radius of the arc is about the same. I do have a Greyhound petrol tank and the the gate from the second Aero, so if I get a chance on the morrow will brave the cold out in the shed and see if I cannot dig the bits out of storage and try offering it up and seeing how close (or not) it would be.

-Doug

douglas1947 · « **Reply #21 on:** 02 Mar 2021 at 14:49 »

Doug,

thanks for the informations.

let us know, if there it is possible to make the later gate fit to the early tank.
May be it is easier to make the small 5mm steel +front srew hole new.

Michael

Doug · « **Reply #22 on:** 02 Mar 2021 at 18:18 »

Unfortunately there is a problem. I can see where the Aero tank (with gate) is stored, but cannot get to it! Not without shifting a bunch of sheet metal (spare fenders, doors, etc.) for one of the old cars. So not something I can get to right away. I had planned on moving the sheet metal to another storage location, so I guess this is an incentive to set a few hours aside and do it.

-Doug

Doug · « **Reply #23 on:** 03 Mar 2021 at 16:39 »

Got some help shifting junk around and was able to get to the 1938 Aero and 1932 Greyhound petrol tanks. So here is what happens when you try to put a 1934-38, 4-speed hand gate on a S6 type tank.

First thing is you install one screw and find for the second that the hole center distance is a little longer on the 1932 tank.

Initially the curve looks to be almost perfect match...

but it ends up against the tank at a crazy angle.

Dropping it to a more correct position opens up a gap and shows the difference in curvature of the two petrol tanks. Here it is touching at the very back and at the bottom tip of the front tab (not visible)

And the gap mount.

A corresponding amount would need be sanded off the both ends to fit it to the tank. And moving the one ear. Without mocking the tanks up on the frames (not presently possible) or a 4-speed S6 gate to hold up to it, do not know if the radius of the gate arc radius is the same or how far off it might be.

-Doug