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Conquest Preselect alignment

Garyhbates
Posts: 54
Joined: Fri Aug 12, 2016 12:21 pm
Location: Faringdon , Oxfordshire

Conquest Preselect alignment

Post by Garyhbates »

I am having problems trying to get the preselector gearbox in my Conquest aligned properly and wondered if anybody has any suggestions on alignment.
I can select any gear i want using the arm on the side of the gearbox. With the inspection cover off the gearbox move the lever to the required position, push change lever and watch the gear being selected on the busbar. The problem is how to remote control this through the rods. There is generally a lot of play in the rods so i have replaced the ball and sockets with new nylons ones . I have also replaced the bushes on the two link arms which transfer the motion around the car. This tightened up the whole movement but i am still not able to select all gears. By careful adjustment of the rods by screwing or unscrewing the last link behind the steering column i can adjust the length of them precisely to align the column shift with the gearbox. I have arrived at a position where i can select a gear and change to it nicely. However , I can not extend this to all gears. I can either have R-N-1-2-3 and no TOP or if i turn the ball and socket by one screw turn i can then get N-1-2-3-T but no reverse . I can not get enough "range" from the selector to be able to span from R to T. My last resort will be to file out the bronze guide behind the selector but this seems extreme. Note that i can select the extreme gears R or T by applying a very small amount of pressure to the gearbox selector.
I do have a spare gearbox that i could try but want to look at other options if there are any first as this is a big job to replace it.

Db n j
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Location: uk shropshire

Re: Conquest Preselect alignment

Post by Db n j »

Gary,

I feel this is a lineage problem, and not a gearbox issue (and is a path trodden by many), so don’t change the box

From a design point of view there is no fine adjustment for individual gears, so finding a compromise is required.

I think Al has provided a step by step guide in the past, (maybe worth repeating).

Since you have replaced ball joints etc, you need to find the best fit

(The Duke has problems sometimes finding Overdrive, so technique is to push the lever as the clutch is released) My theory is that the riod gets a fraction extra travel which allows selection (but I have tried adjusting the rods and only made something worse)

Patience !!

Petelang
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Location: Nottingham
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Re: Conquest Preselect alignment

Post by Petelang »

Check there is nothing whatsoever fouling on the shafts or levers.
Its taken me several years but I eventually found a tiny amount of chaffe on one rod which just prevented proper selection on my Siddeley.
You have to be meticulous.
Peter
Last edited by Petelang on Sun Oct 25, 2020 12:13 pm, edited 1 time in total.
Peter Langridge
Cloud Nine Classic Weddings, Nottingham.

bakergh
Posts: 109
Joined: Wed Feb 24, 2016 1:57 pm
Location: New Forest, Hampshire

Re: Conquest Preselect alignment

Post by bakergh »

Check the selector arm on the gearbox is truly perpendicular. If it has been even slightly bent either into or away from the gearbox you will have the selection failure you describe.
Took me ages to find this on my car.

Graham

Garyhbates
Posts: 54
Joined: Fri Aug 12, 2016 12:21 pm
Location: Faringdon , Oxfordshire

Re: Conquest Preselect alignment

Post by Garyhbates »

Thanks for the suggestions, the route is clear , i reversed one of the balljoints on the top link arm to move the top link further away from the rocker box as it was too close for my liking. Since the replacement balljoints were metric threads i remade two of the rods with fresh 6mm steel , so they are very straight. they all have locking nuts to ensure they are rigid.
The selector arm has had a bashing but it's fairly square with the gearbox.
IMG_1505.JPG
Its not very clear from this photo but the tab that holds the ball joint is probable not absolutely vertical , its about 15 degrees off , will try to straighten it up !

JT7196
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Re: Conquest Preselect alignment

Post by JT7196 »

Hi, I would suggest that you disconnect the linkage at the Quadrant, then manually select Reverse Gear on the Gearbox by pushing the selector lever fully Rearwards.
Having done this, the adjust the length of the Rod so that it just fits snugly onto the Quadrant , hopefully this should solve your gear selection problem.

Cheers Al 😊😊😊

Stan Thomas
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Location: Penkridge. Staffs.

Re: Conquest Preselect alignment

Post by Stan Thomas »

Try this.

Given you can select all gears by moving the lever on the gearbox means the problem is there is insufficient stroke of the selector mechanism relative to the movement of the lever depicted in the picture you have posted.

Imagine the arc swept by the linkage. If you bend up the lever a little it will efectively increase the sweep of the arc - which should allow all gears to be selected.

bakergh
Posts: 109
Joined: Wed Feb 24, 2016 1:57 pm
Location: New Forest, Hampshire

Re: Conquest Preselect alignment

Post by bakergh »

Once you have checked that all the linkage is correct and not bent you need to adjust the rods correctly.
As Al has said disconnect at the selector above the steering column and set set the long rod to to match the gear selector in reverse gear but then set the gear selector to top gear.
Disconnect and push the linkage to the top gear position, Note the difference between the selector ball and the long rod cup
Adjust the long rod to halve the distance between the ball and cup.
You will now have balanced the difference and should now have top and reverse gears operating.
I do not think the gear selector was designed to take the gearbox selector right to its end stops.
Graham

Garyhbates
Posts: 54
Joined: Fri Aug 12, 2016 12:21 pm
Location: Faringdon , Oxfordshire

Re: Conquest Preselect alignment

Post by Garyhbates »

I have been through the process of adjusting the rods many times but the core problem is that of achieving enough range or travel. Thanks Stan and Graham, I had not considered the quadrant arm and i can see that if this is bent in towards the gearbox it will not achieve as much travel as if it were truly square . Its only bent in a tiny amount but i have found that the difference between selecting one gear and another is hardly visible when you push on the quadrant slightly at the extremities of the travel .
I agree with Graham that the travel on the quadrant is much greater that the travel given by the selector mechanism but i just need another 0.25mm at one end to get all the gears !

Stan Thomas
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Location: Penkridge. Staffs.

Re: Conquest Preselect alignment

Post by Stan Thomas »

Hi,

I think you mis-read my earlier post. The angle of the bend in the selector lever where the ball-joint attaches is irrelevant.

Just increase the angle of the bend in the thicker section of selector lever which will then shorten the effective pitch circle - causing the selector movement to circumscribe a greater arc.

Trust me.

Stan.

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