I have a 72/73 Bay, fitted with a later auto box. The accelerator cable seems to be a bit of a bodge, as it has to run in a new conduit to the other side of the engine, vac boxes appear to have accelerator cable exciting from left as you look from rear, later boxes, the cable goes to the right ( UK drivers side ). My problem is with adjustment, I have the fixed fitting at the gearbox end using a universal cable, make my adjustments at the pedal linkage end. My problem is as follows..............when I got the van it ran with the cable pushed through the hole on the lever, pulled back on itself and fastened with an electrical connector. I thought this couldn't be the best option, so had a hole drilled in a bolt, so that I could tighten using a nut either side of the cable....this eventually sheared where the hole had been drilled. I then moved on to using a brake cable adjuster stolen from my sons bike....figuring that at least it was designed for the purpose.....this however is fraying the cable badly. To cut the above long story short.....what can you guys suggest to provide adjustment at the pedal end ..I basically have the bare cable and a hole in the end of the linkage and need to join the two ! Thanks in anticipation.
Ive a suggestion but it may involve further work: buy a length of bicycle brake outer cable from a decent bike shop (ie off the roll) make an L shaped bracket that bolts up under the floor an inch or so behind the throttle pedal to provide a cable stop buy a length of galvanised 3mm cable from B & Q off the roll fit the bike barrel adjuster on the outer cable side of the stop bracket loop the bare cable end over to form an eye and use a good quality crimp to keep it in place bolt the eye through the hole in the pedal make another cable stop at the engine/gearbox end route the cable (inner/outer) via the least convoluted route adjust cable length via the barrel adjuster OR....if the original cable tubing is OK, just go for the eye/crimp fix....or possibly a large solderless nipple...or seeing as you're into stealing your sons bike components, why not adapt a traditional side pull brake cable clamp bolt to jam the cable against the side of the pedal arm. This last suggestion is probably the best option IMO The issue lies in the fact that the cable angle changes as it gets pulled through...hence the chaffing...a guaranteed method to stop this, and incidentally, transform your pedal into a super smooth action, would be to fit a cable roller between tthe pedal arm and the end of the conduit Enjoy mulling over the options....
Should have known who would have replied......almost directed the post directly to you initially ! I am presently using a side pull brake clamp bolt as you have shown, but I was concerned that the cable had frayed rather quickly. I had wondered if reversing the connections......i.e. putting the fitted cable end to the pedal, as per VW Heritage parts picture and having the brake clamp bolt at the gearbox end would reduce the wear / strain on the cable. At least I know I am on the right track ! Thanks for your reply, much appreciated.
Use the threaded adjuster you get with carbs. The cable passes through the end and there is a ball joint in the end. Fit the ball joint to the pedal et voila you have an adjustable cable
Cheers Joker, would there be a threaded adjuster on the standard carb set up ? I have the old carbs in a box in the garage that I can scavenge off. If not, where can I get one from ?
Here's another suggestion.. Looking at the above pic of a master cylinder pushrod kit: make up a bracket similar to the one in the bottom left hand corner open end goes over the pedal arm and is held in place with a bolt or clevis pin (bottom right)....make sure that this bracket is floppy cable threads through a hole in the closed end and is held in place/adjusted via a solderless nipple This will reduce friction as the cable gets pulled, since the angle will change....
The RAC fitted a bracket and clevis pin set up to get me home when my original bolt with a hole in it sheared. Never occurred to make this adjustable as I didn't think there would be enough space in gap between pedal arm .... will have a look tomorrow and experiment You really are a mine of information / ideas. Thanks again.
Thanks Joker, I have the Haynes manual in front of me...can you tell me the number of the bit you suggest ? Sorry for been a bit thick !!
Latest update:- Put a new pedal bracket on, mounted in original holes. Fitted a longer pedal lever that cable connects to and my problems seemed to have gone......I did say seems ! As I have a late auto-box, the accelerator ends at the kick down lever and as I have a progressive choke carb fitted, a further wire goes to the carb. The problem appears to be the different amount of movement required by the cables......the cable movement required from pedal to fully operate the kick-down lever is less than cable needs to move to fully open the carb...hence carb can't operate at max. If I ran a new inner and outer cable from pedal to carb, bypassing kick-down lever, I would think this would result in lighter throttle but no kick-down. This would mean that if I had it in drive, the gearbox would operate as normal.....if I need to a sudden surge of power to overtake ( alien words to auto bay owners I know. ) then I would have to manually drop down to 2nd. If I have fundamentally misunderstood how the gearbox works, will somebody shout out....equally if there is some logic to my idea, some confirmation would be appreciated. This problem is giving me sleepless nights !!
Not got an auto in, but perhaps you need to find the total cable pull required for the standard carbs, then "adjust" the lever on your cab so fully closed to fully open requires the same amount of cable pull as the standard set up. By aping the original I would imagine it would work and saves having to completely understand how it all works. You should be able to do this by making the operating lever on you carb the same length from spindle centre to pull point as the originals. Sorry in advance if I've misunderstood the problem.
I've been having a similar problem for a good few weeks now and it's got to a point that I've almost given up and not been to the van for a couple of weeks as I know I'll come away peed off after having not achieved anything again!! Replaced old progressive carb with a webber twin choke progressive and thought straight swap will be done in a day! Couldn't be more wrong Couldn't get it to open fully at full throttle Fiddled for a few days with no joy Noticed under the old carb was 3 alley plates which sat the old carb higher and also an extension plate on throttle arm (bugger) Took off and added these Still the same (bugger) Tried many different hole positions for cable still no joy Took off extension plate on throttle arm and drilled a hole in the original closer to pivot point (yeeeehhaaaa) opens fully!!! But now when you press the peddle it only starts to work halfway down and you really don't have much control of throttle at all (bugger) So have spent ages now fiddling adjusting refiddling readjusting pulling pushing screwing unscrewing in many different combinations and still no joy It doesn't help I guess the way the cable from kick down to carb is routed with some mystery cable tensioning parts from a ford but have tried every combination I'm sure and nothing How/where does your cable enter the engine bay and go to the carb?
What I should ad is drilling the hole closer to the pivot point on throttle arm did make the carb open fully!( It was only by a couple of millimetres ) basically as far as you can go before the raised part The problem with the throttle pedal not working till half way down I believe is not to do with this as I have changed back to the original holes for the cable to see what would happen and still didn't work so I can only guess its the routing and adjusting of my set up. I've played around so much with it I can't work out how it was before
Your last sentence sums up my position, I got a better throttle by replacing/repositioning pedal and longer extension plate, went a run and was OK but not right. Had a play and now can't get a decent throttle at all! My system is standard up to kick-down lever, then a bike type cable from kick-down to carb using fabricated brackets. It just comes through an existing hole in tinware near where carb pre-heat tinware tube comes into engine bay. Since I had the carb fitted, it worked but never got full throttle opening. Still think by-passing kick-down I will have a better pedal, because the standard auto set-up ain't half heavy ! Any experts out there who can comment before I go out to the local cycle shop for cable ?
I'm not familiar with the cable arrangement for a kick-down set-up, but I think you are on the right lines in thinking that the original mechanism needs to be reconfigured to account for the changes made from stock. Whichever way you look at it, it's a simple mechanical arrangement...movement at one end of a cable produces an equal amount of movement at the other, regardless. Only when yo start to add multipliers will this change. The throttle linkage on a carb is not a multiplier; You need to go back to first principles and measure the total amount of movement required to rotate the throttle plate from fully closed (or where it rests on the idle stop) to fully open...to do this tie a piece of string to the throttle arm....run the string along the edge of a ruler....pull the string and measure....that's how much travel you need. Whether the cable is linked directly to the throttle arm, or goes around a pulley it's always the same measurement. So Id consider looking at the way the throttle linkage is fixed to the carb and modify by lengthening/shortening/drilling or whatever it takes. to get the cable routing from pedal to carb as free from convolutions as possible. Re the travel required....your standard throttle pedal set-up is basically a pivoted lever ....it has more than enough travel (and leverage) to pull the amount of cable required at the carb end....the actual height of the pedal is largely irrelevant...it just so happens that VW used a carb(s) requiring a certain amount of cable movement to operate, so designed the pedal (in terms of length and angle) to satisfy that requirement (in practice if it was cheaper to use the same pedal arrangement and modify the linkage at the carb end, they would have done this...they probably did both) Anyway, this doesn't solve your problem, but it may set you thinking about what you need to achieve, rather than what have I not understood. Also....look at it in terms of bits of metal and linkage, that if bent one way, or fixed another, has the desired effect....sod what VW did originally...fettle something bespoke with bits that will do the necessary And then post some pics and info how you achieved it
Cheers for that vanorak, I am going down the new outer and inner cable from pedal pivot to carb, just to see how much it improves the "feel" of the pedal. Obtained a length of outer from bike shop. Inner I intend to use a universal cable, which should be long enough to go straight down the length of the bus. The main reason for doing this is to utilise the S or Z connecter at the pedal end and make adjustments at the carb. I always drive using the gearbox as a semi-auto, dropping to get some speed up and to gain engine braking coming towards junctions anyway. Will have string and ruler out later to calculate cable movement at carb end. I'm betting the stock VW parts at front will give adequate leverage without further mods.
as a general rule (on bikes at least) if the cable outer is free to move around a bit, rather than clamped up with cable ties etc. you get a smoother action
Ok, thanks for that.....had intended using a whole packet of cable ties to keep it rigid.....will take you comments on board.
