Esprit S3 N/A throttle mecanism

[Esprit_Emperor]

Hello!

I'm working on my Esprit S3 N/A 1984. I would like to change the throttle cable . I wonder if anyone have got photos on how the throttle mecanism should be set up because my throttle cable is has a very strange set up. As shown in the picture the throttle cable goes around the airbox and down to the mecanism. Never seen this.

Thanks for your help in advance.

Fred

[slewthy]

Essentially, you need two points - one fixed (cam cover bracket) and another mobile (throttle lever)

Mine is simply the reverse of yours. The throttle cable approaches beneath the carbs and abuts the throttle lever. The cable then passes up to the cam cover bracket and the 'olive' is fixed there.

Both setups work but I think the later is neater but perhaps not quite so obvious in its operation.

I would take a pick but mine is in bits. You wouldnt send me one when you've worked it out would you!?!?!?

[peteyg]

Hi Fred,

I have the reverse setup like Simon. Hope this helps!

Pete

[Esprit_Emperor]

Thanks guys!

Yes, it helps i think i have all the parts mentioned. I still don't get it in theory since i don't have the car nearby until next weekend. Anyone have photos on your factory version setup between the carbs?. When i think about the set up you just connect/run the cable through the lever and up to the olive/bracket. And the wire somehow pushes the throttle mecanism? there are no info about this in the Esprit S3/turbo service book. Any ideas which is the best setup of the two? i belive in the factory version for sure with the much shorter cable.

//Fred

[esprit s2]

I seem to remember that with the Esprit the outer jacket of the throttle cable is the bit that moves and the cable itself is held at both ends. Hard to explain.

[Esprit_Emperor]

Thanks!

Anyone else have an photo/idea?

bumper

/Fred

Edited May 7, 2010 by Esprit_Emperor

[scottmgibb]

The Esprit throttle cable works by witchcraft. Simple.

I replaced it all a couple of months back, and still don't really understand how it works! The cable moves at the throttle peddle end (it is pulled as you push the peddle), but is fixed to the cam covers at the other end - somewhere inbetween the movement changes to the jacket (which pushes the carb throttle forward). I have always ment to draw a diagram to try and get my head around it...

Pete's picture is, I believe, the factory set-up - do you want a photo of something specific?

Scott

[slewthy]

Witchcraft it may be but the logic is reasonably straight forward

Depressing the accelerator pedal pulls the cable through the sleeve - yes?

Therefore, at the engine end, the distance between the sleeve end and the cable end shortens - ummm?

If the sleeve end is at the throttle lever and the cable end at the cam, the only way for the above mentioned shortening to occur is if the throttle lever to cam cover distance shortens also, the throttle lever advances.

Its is extremely important that EVERY time you depress the accelerator pedal, you think through this entire process. I cant emphasise that enough.

The brake pedal now - THATS smoke and mirrors!

Edited May 7, 2010 by slewthy

[scottmgibb]

Yeah, that all makes sense, but what I have never really got my head round is how that happens. When you push the throttle peddle the cable is pulled out of its jacket, and if it wasn't connected to anything then the other end of the cable would eventually disappear into it. But when connected to the car, the end of the cable is fixed, so how can it be extended...? If I tie a rope to something and try and pull it it doesn't extend... it’s witchcraft I tell you! I am going to be working on the car tomorrow, so I am going to have a proper look at it. Once and for all I will comprehend this!

The brake peddle has nothing on this!

Scott

[slewthy]

OMG, you are totally right. How can anything move if the cable is fixed at both ends.

Interestingly, if you operate the throttle in the engine bay, the cable protrudes 'loosely' through the cam cover bracket end thing.

OK, I admit it, I'm confused but perhaps this is the explanation for this paradox...

The Cable is not straight. The reason the pedal can be pressed at all is because the cable is being straightened.

It does so by 'taking up the slack at the pedal end. Since the sleeve can also straighten, it does so, however, the sleeve is fixed at this point and therefore there HAS to be a corresponding movement at the engine end. Perhaps therefore in a nutshell, this could be described as 'differential straightening'

Convinced? No, neither am I but I cant explain it any other way. I'm starting to think that the only way I'll get mine to work again is if I invite Gandalf around for a beer or two and ask him to do a really difficult trick with a wire and a tube....

Edited May 7, 2010 by slewthy

[matk]

Could this be the answer?

http://en.wikipedia.org/wiki/Bowden_cable

[Esprit_Emperor]

The Esprit throttle cable works by witchcraft. Simple.

I replaced it all a couple of months back, and still don't really understand how it works! The cable moves at the throttle peddle end (it is pulled as you push the peddle), but is fixed to the cam covers at the other end - somewhere inbetween the movement changes to the jacket (which pushes the carb throttle forward). I have always ment to draw a diagram to try and get my head around it...

Pete's picture is, I believe, the factory set-up - do you want a photo of something specific?

Scott

Hello,

Sorry for this late replay Scott i had some family weekend business thing going on. What i need to see on a photo is how the set-up between the carbs is mounted etc. and if the outer cable goes in to the lever etc. Ordered a new wire and outer cable last week. Really looking forward to get it back as it should be.

//Fred

Thanks guys,

for all your interesting thoughts on this subject, keep em coming. When i changed the choke cable i pushed the outer cable through the hole from the engine bay but the throttle cable is probably best to push through from the coupé?

//Fred

[peteyg]

Here you go Fred.

The spring then clips onto a hole on the underside of the airbox.

Pete

[USAndretti42]

The one end of the outer cable is not fixed. It's attached to the throttle lever so, when you press the pedal, you pull inner cable trough it and, for every inch of cable you pull out at the pedal end, an inch goes in at the throttle end. Simples. No witchcraft involved.

Usually the cable comes up under the airbox to the throttles with the inner going on to a bracket on the cam cover or over the top with the outer fitting to the cam cover and the inner going to the throttles. It's pretty easy to replace the whole assembly if you tape the new cable to the old one and use the old one to pull the new one through. You will probably need to remove the pad on the centre tunnel to do it, though.

[slewthy]

The one end of the outer cable is not fixed. It's attached to the throttle lever so, when you press the pedal, you pull inner cable trough it and, for every inch of cable you pull out at the pedal end, an inch goes in at the throttle end. Simples. No witchcraft involved.

Yep, but the witchcrafty notion was this - how can you pull the inner cable through at all - its fixed at the engine end!!!

Hence my differential straightening theory.

[USAndretti42]

Yes the cable has to be bent for it to work.

[Esprit_Emperor]

Hello,

I finally changed throttle cable outer and inner to the factory version. At the same time i changed the pedalspring, airbox spring. Sprayed the pedals and put some new satin black colour on them and new pedal rubbers. (I also changed the choke cable at the same time).

My version i had was worthless to the Bowden version. Better response at the gas pedal etc. It was really easy/ and fun to do and a worth every penny.

A photo of the lever mecanism below.

/Fred

Edited May 19, 2010 by Esprit_Emperor

[slewthy]

Nice. I imagine that was quite satisfying.

Where did you get the pedal rubbers and did you keep the gas pedal 'bare?'

[Esprit_Emperor]

Yes, it was very satisefying. I keep the throttle pedal bare i think thats the factory setup? a good pair of shoes is the key.

//Fred