Accelerator Cable and Kick-Down at the Manifold

[richardlamsdale]

Would anyone have any photos of a correct later accelerator linkage and kick-down setup (I'm interested in the later type, not the early type as per the manual - my car has the kick-down linkage behind the manifold, not attached to the carb). Specifically, I'm trying to answer the following:

- The end of the accelerator cable attaches to a pivot arm on the manifold which has the nylon roller attached that actuates the carburettor. There are two holes in the pivot arm at different distances from the pivot point - which should the accelerator cable attach to? And what's the other hole for? My car has never had a sprint attached to this pivot lever, but I've seen this in at least one photo on this forum. If there should be a spring, where does it fix to?

- The kick-down mechanism attaches to this pivot and travels rearwards via a spindle to the cable behind the manifold (the rear bush had been lovingly replaced by a rubber grommet - I'm making a brass replacement). Should there be a spring on the kick-down lever, or does it rely on the carb mechanism springs?

Before I disassembled things everything 'sort of' worked, but the accelerator linkage was quite imprecise, not always returning to slow tick-over, so I'd like to get this right now I'm re-building things.

Any info would be useful, as the manual only shows the earlier setup (and even then not that clearly). Thanks.

**edit**

It was Colin McA's photo that has made me question whether I should have a spring on the pivot arm:

roverp5.proboards.com/thread/5669/carbs-mechanism-returning-v8

[eightofthem (Andy)]

From above.

From behind ( courtesy of CYF ) you can see where the bush should go ( red circle ) and how the spring is set up. ( the blue square shows the kick down cable )

[johnwp5bcoupe]

Feb 26, 2015 18:11:29 GMT eightofthem (Andy) said:

From above.

From behind ( courtesy of CYF ) you can see where the bush should go ( red circle ) and how the spring is set up. ( the blue square shows the kick down cable )

OOOOH Andy an AED

[eightofthem (Andy)]

Thought you would like that John, I still have it fitted! ( although I do have a manual choke cable fitted in the event it fails, then I can at least get out of jail until I fix it again. )

[johnwp5bcoupe]

Feb 26, 2015 18:32:07 GMT eightofthem (Andy) said:

Thought you would like that John, I still have it fitted! ( although I do have a manual choke cable fitted in the event it fails, then I can at least get out of jail until I fix it again. )

Made my day Andy

[richardlamsdale]

Thanks Andy, the photo of the kick-down is exactly what I was after...I seem to be missing a spring. For the bush I was planning on using an m12 or m14 brass bolt machined down and drilled through it's centre for the spindle, then bolting it through the bracket. Maybe not perfect but better then a rubber grommet.

You wouldn't happen to have any other photos of the lever where the accelerator cable attaches would you? Is there a spring attaching to that as well?

[eightofthem (Andy)]

There are two springs shown in the picture, they are both clipped to a bracket ,which is held down by one of the manifold bolts on each side.

If you look closer at the picture with the red circle and blue square ( CYF, s ) above, then you can see one of them in position, also another larger spring has been added, you can just about make it out.

[richardlamsdale]

Thanks again Andy, you're right, I can see the springs in Cyf's photo now you point them out. I have the tabbed washers under the 3rd-from-rear manifold bolts, and I have springs attached to each carb from these, but there's no spring on the pivot lever that the accelerator cable attached to. So that's another spring I'm missing.

This all explains why the throttle wasn't fully returning to idle (that and the grommet for the kick-down which must have added a lot of friction). Luckily I bought new carb springs recently from Wadhams, so might try to re-purpose the old ones for the pivot and kick-down.

Appreciate you help. Thanks.

[eightofthem (Andy)]

No worries.
One thing to check is the throttle cable itself is not corroded internally, this will cause sticking and non return.
My cable looked good but was totally shot inside, and played hell with my attempts to get it idling correctly, once a new cable was fitted is was good as new.

[petervdvelde]

Richard,

On my P5b, the rubber bush for the kick down mechanism was also missing. I took a set up from an old PAS fluid container and cut a piece off from both sides and increased the diameter of the hole with a drill. The top nipple is the original one and the one underneath is the modified one





regards

Peter

[barryr]

That looks like a good idea! I had half a grommet left holding mine so I coated the spindle in wd40, made a plastercine mould for the outside of the grommet and recreated one using a product called plast-aid see here:

www.plast-aid.com

[richardlamsdale]

Thanks Peter, thats similar to what I was thinking. Barry's idea of using a plastic putty is a good idea as well - some of these mouldable plastic products are quite interesting - I fixed a split in my steering wheel using something similar, but the smell from the plastic solvent was really quite something - I had to leave the windows and doors of the house open for a couple of hours in the middle of winter. Maybe I shouldn't use the kitchen as my workshop.

[petervdvelde]

Feb 26, 2015 22:17:31 GMT richardlamsdale said:

Thanks Peter, thats similar to what I was thinking. Barry's idea of using a plastic putty is a good idea as well - some of these mouldable plastic products are quite interesting - I fixed a split in my steering wheel using something similar, but the smell from the plastic solvent was really quite something - I had to leave the windows and doors of the house open for a couple of hours in the middle of winter. Maybe I shouldn't use the kitchen as my workshop.

Richard,

You are right saying that the setup is identical to the bolt solution you have but without access to a lath, it will not be easy to drill the hole in the center of the bolt and this could lead to friction in the shaft. The nipple i used already has a hole and it can be enlarged without a lath and will remain centered.

Peter

[richardlamsdale]

Feb 27, 2015 8:03:28 GMT petervdvelde said:

Feb 26, 2015 22:17:31 GMT richardlamsdale said:

Thanks Peter, thats similar to what I was thinking. Barry's idea of using a plastic putty is a good idea as well - some of these mouldable plastic products are quite interesting - I fixed a split in my steering wheel using something similar, but the smell from the plastic solvent was really quite something - I had to leave the windows and doors of the house open for a couple of hours in the middle of winter. Maybe I shouldn't use the kitchen as my workshop.

Richard,

You are right saying that the setup is identical to the bolt solution you have but without access to a lath, it will not be easy to drill the hole in the center of the bolt and this could lead to friction in the shaft. The nipple i used already has a hole and it can be enlarged without a lath and will remain centered.

Peter

I agree Peter, and I don't have a lathe, but I can't find anything that is already pre-drilled and has a large enough external diameter, nor do I have an old PAS reservoir. I'll keep looking, but I think almost anything will be better than the grommet (or leaving it with no bush at all, as I've seen on a few cars) so I'll try a few different things. I think with careful drilling and reaming I can make something that works, but we'll see.

[Welsh Warlock]

Feb 26, 2015 22:17:31 GMT richardlamsdale said:

Thanks Peter, thats similar to what I was thinking. Barry's idea of using a plastic putty is a good idea as well - some of these mouldable plastic products are quite interesting - I fixed a split in my steering wheel using something similar, but the smell from the plastic solvent was really quite something - I had to leave the windows and doors of the house open for a couple of hours in the middle of winter. Maybe I shouldn't use the kitchen as my workshop.

This stuff is pretty good for that sort of repair and has no smell. Sets to a hard rubber texture. sugru.com/

Sticks well to most things but can be made not to stick where required.

[barryr]

Plast aid is not flexible like sugru - it's harder.

And like Richard said, plast aid absolutely stinks! ( ok once set)

[richardlamsdale]

Been working on the car today and I'm still not sure where the return spring for the accelerator lever should fix. I tried it on the tab under the manifold bolt (shared with the carb spring), but due to the angle it only actually pulls the lever back over the last ½ of travel - it's basically opening the throttle over the first ½ travel. The best anchor point would be as per Colin McA's photo from this thread (roverp5.proboards.com/thread/5669/carbs-mechanism-returning-v8), so the spring is pulling directly back against the cable, but obviously that isn't standard.

I'm going to make a tab to go under the rear rocker cover bolt, as that's the only place I can see might work. Will update when I've tried that.



I've come up with another option for the kick-down mechanism bush - threaded nylon rod. Easier to machine than brass, and nylon was the factory solution. I've ordered some 16mm threaded rod and nuts off eBay, and will drill a hole to match through the centre. The hole in the kick-down bracket is only 14mm so that will need opening out slightly, but I just can't find 14mm rod anywhere.

[Phil Nottingham]

About 15 years ago I just used a nylon nut (s/h!) from a toilet seat hinge. It had 2 wings and these just needed filing down a little which also increases its bearing surface which I made tight. Still going strong

[Deleted]

Feb 28, 2015 18:02:34 GMT richardlamsdale said:

Been working on the car today and I'm still not sure where the return spring for the accelerator lever should fix. I tried it on the tab under the manifold bolt (shared with the carb spring), but due to the angle it only actually pulls the lever back over the last ½ of travel - it's basically opening the throttle over the first ½ travel. The best anchor point would be as per Colin McA's photo from this thread (roverp5.proboards.com/thread/5669/carbs-mechanism-returning-v8), so the spring is pulling directly back against the cable, but obviously that isn't standard.

I'm going to make a tab to go under the rear rocker cover bolt, as that's the only place I can see might work. Will update when I've tried that.



I've come up with another option for the kick-down mechanism bush - threaded nylon rod. Easier to machine than brass, and nylon was the factory solution. I've ordered some 16mm threaded rod and nuts off eBay, and will drill a hole to match through the centre. The hole in the kick-down bracket is only 14mm so that will need opening out slightly, but I just can't find 14mm rod anywhere.

Richard, I don't know if you're still needing help on this but I took a photo of my linkage today just before going out in the car. I have a later kick down set up with a manual choke rebuilt a long time ago.There is only one spring on each side with a large spring on the kickdown.


 

[Deleted]

Mar 2, 2015 17:08:08 GMT @resurgam said:

 

[Deleted]

Mar 2, 2015 17:10:08 GMT @resurgam said:

Mar 2, 2015 17:08:08 GMT @resurgam said:

 

A couple more images:

[richardlamsdale]

Thanks, that is really useful. It's tricky to work out what's original, but I do think your setup is probably right - a spring on each carb plus the kick-down spring. The fact there's no obvious way to anchor a spring for the accelerator lever (there's a spare hole in the lever but nowhere obvious to attach the other end - the washer under the manifold bolt where the carb spring anchors is too near the accelerator pivot) makes me think there shouldn't be one, but that the kick-down spring performs the same function. Thanks again.

[Deleted]

Mar 2, 2015 17:38:57 GMT richardlamsdale said:

Thanks, that is really useful. It's tricky to work out what's original, but I do think your setup is probably right - a spring on each carb plus the kick-down spring. The fact there's no obvious way to anchor a spring for the accelerator lever (there's a spare hole in the lever but nowhere obvious to attach the other end - the washer under the manifold bolt where the carb spring anchors is too near the accelerator pivot) makes me think there shouldn't be one, but that the kick-down spring performs the same function. Thanks again.

No problem, glad it helped.The set-up you see is original but my car originally had the AED and I converted to manual choke 20/25 years ago. I don't recall making changes to the throttle linkage, I just had to connect the the mechanism to lower the jets.It all functions very smoothly and the grommet for the kickdown is in place even if the kickdown isn't working!

[petervdvelde]

Richard,

There are 2 special washers underneath the manifold bolts which have a small hole to fit the spring. I believe your spring is not the right one being too long.

Peter

[Colin McA]

The gromit was remanufactured by rover classics so will be available from wins international quite cheap. I bought 2 when I got mine.

Colin