Choke will not set with accelerator

[Eloise]

Fast idle screw is on the right step, everything is free to move by hand. Taken off the choke spring. Can push the flap down and arms and springs and set it on the right step on the cam. Trouble that I have is that there is nothing I can do to make this happen by pressing the accelerator? There is absolutely no conection on the spindle to set this choke when the pedal is pressed or worked by hand? I would have expected a tang and ramp type of set up somewhere but it's missing? Can anyone elaborate or show me how this works please?

Cheers neil

[kevtherev]

The ambient temperature is not cold enough for full choke.
As the acc. is depressed the rotating butterfly spindle kicks the fast idle cam, and releases the choke flap to rest in it's ambient temp position.
It will engage the uppermost step if properly adjusted, but in warmer weather I am unsure if this happens,( it doesn't on my spare carb, but it isn't adjusted to run)
It will disengage as soon as the acc. shaft rotates and the springs will centre it to the choke position

setting this up is described in the haynes and in more detail in the Bently manuals
Removal of the carb is the only way to clean and ensure all the springs are attached properly, plus you see and understand the entire mechanism

[Eloise]

There is absolutely no movement of the choke flap, or setting of the fast idle cam when I press the accelerator. I can put it manually on to the fast idle cam, both second step (with gap in choke flap) and the top step (no gap, flap completely closed). To do this, I have to open the throttle fully and press down on the rear of the spindle where the arms and springs are. This will hold it there till accelerator is pressed again, this then springs open again. This is with the choke spring housing removed.

If I put the housing back on, is the spring supposed to spin the cam round under pressure? Unless it's warm? I.E. When cold, is it the springs task to set the fast idle cam with the throttle pressing?

Carb off next I think to try and work out what's missing or mal adjusted.

Cheers.

[Verne]

When I took mine off, I'm 90% sure that the spring wasn't even on the arm.



Pic ' borrowed' from thread on ClubGTi - full thread may help

Not just T25s that suffer with the Pierburg

[Eloise]

Thanks Verne, mine is connected but it still will not set or work the fast idle bit. It's like everything on the spindle has all spun round out of place.

Cheers

[Verne]

I'm expecting some fine tuning, but mine is now a lot further round than when I took it off. Have you tried turning it to the extreme?

[Eloise]

Yes, I tried that but I had to turn it fully clockwise to close the choke flap. The screws were at their limit of adjustment. That can not be right?

Will remove and dis assemble it. I just don't want to remove the coolant hoses and have to bleed the system again, that's what's stopping me having it in bits.

Cheers

[Eloise]

Where is the best place for the base and insulator gaskets?

Cheers

[kevtherev]

Gower & Lee
you won't lose hardly any coolant.
what is lost will be replaced by the top up tank

[Eloise]

Hi Kev, is it wise to clamp the cables? I think I will remove it and investigate it today as all other plans seem to have been rained off

I will take photos of what I find and will prob be asking lots of questions

Cheers Neil.

[kevtherev]

just take it off it's dead easy and you don't need to clamp.. well I never have.
VW made it fixerfriendly..

just remember it's full of petrol.

[Eloise]

Yep, cheers for that, I had better remember to empty it via the overflow. Of to tackle it now.

Cheers neil

[Eloise]

Sorry, having trouble figuring out how to use photo bucket.

Found the problems, thanks to you guys on here. If the photos have loaded correctly, you can see the movement I have on the spring, note the positions of the square tang. The spindle is loose! I have found the grub screw thanks to mr feet, and it is free to move.

What I need is roughly the position for about 12 degrees which it is at present? Mr feet put up a photo of one at zero and also other markings on the case. I think the far one is 24 degrees? If you can confirm this, I will put it in a position roughly half way between zero and 24.

Many thanks for your help

Neil.

[Eloise]

This is mr feets photo. I think it shows zero and plus 24 degrees. Can someone confirm this please

Cheers neil

[itchyfeet]

My writing says minus 10 degrees, 10 degrees and 24 degrees
the actual position in the pic is as the thermometer says at zero ( was taken in winter)


so you should really set your own choke up as they may all be slightly different but thats probably a good start copying the pic after putting it in the fridge, may need to turn the fridge up to get it to zero