Autostick Jerks Constantly

Started by Breeze, 23 January 2021, 21:48

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Breeze

Hi all, I bought a 71 super beetle autostick in September.  The car had been sitting for 8 years and was not running when I bought it.  My son and I have been slowly bringing it back to life.  The vwar tech forum has been my go to for troubleshooting the Autostick system and many thanks to the frequent posters and their wealth of knowledge. 
We managed to get it running pretty good and the valves have been adjusted, it's been static timed and the idle has been set by ear (no timing light or tach).  The clutch disc was stuck and we were able to free it by jacking the rear wheels up, starting it in Drive Range 1, revving it up and then braking while engaging the clutch servo.  We drove around for three days in October and the Autostick system seemed be working well other than shifting pretty suddenly when shifting from a stop into low range or reverse. 
I took it for a drive two days ago and started out in low range (lr) then shifted to drive range 1 (dr1). When it shifted from low range to (dr1) it jerked constantly and the only thing that would stop the jerking was to stop the car, shift back to (lr) or shift to neutral.  It will shift into and drive in low range and reverse but as soon as it is shifted into (dr1) it will start jerking.  I tried starting from a stop in (dr1) and it shifted into gear but as soon as I tried to accelerate it started jerking constantly. 
I am not sure what to try at this point and hoping someone knows the fix to this problem.
Thanks

bhartwell59

Have you adjusted the control valve?

Does it shift ok? Might explain the jerkiness but usually only going into gear.
1974 zambezi green Ghia vert

volkenstein

Breeze,
          Nasty - engine/trans or vac system. Well - try this electrical isolation - wire in a test light to the connection out of the gearstick. Check what is happening when jerking occurs. The light will go on/off and stay off when you have completed the gearshift and Stay Off! Any blinking and you are tracing wiring. It is bizarre that your solenoid appears to trigger badly when in DR1, although the gearstick positions are different between LR1 & DR1. What about Top/DR2?. I'll try and dream up some more simple tests.


HTH
Volkenstein
'71 RHD A-S Super - "Klaus"

Breeze

Hi Volkenstein
I will try the test light on the shifter contact to see what happens.  I have adjusted the control valve and was not able to reduce the constant jerking when shifting into drive range 1.  When we first got the car running it started in all gears except for reverse.  I pulled the neutral start switch and it bench tested fine but I did notice that the nose on the end of the switch is all hacked up and looked like it had been gouged by the action of shifting.  I put the switch back in and was still able to start in all gears except for reverse but the car was driving and shifting fine.  Before the car started jerking I had managed to find a used neutral start switch which also tested fine and I installed it only to find that the car still started in all gears except for reverse.  I can't imagine that the new (used switch) would cause the car to jerk the way it is but I am going to swap out the switch back to the original one and see what happens.  Will also try starting from a stop in drive range 2 and shifting from low range to drive rang 2 to see if it jerks or not. 
Thanks for your help on this one.
Breeze

volkenstein

Breeze,
          Just had two nasty thoughts together ::)..
1. Can you check and make sure ALL your large bore (12mm) vacuum hoses are the wire reinforced type?
2. Check your distributor advance mechanism isn't frozen - mechanical & vacuum.

I do think your car has suffered P.O. syndrome and you should check for non-standard setup's.


HTH
Volkenstein
'71 RHD A-S Super - "Klaus"

Breeze

This car is possessed and is definitely suffering from PO syndrome. 

It has the pict 34-3 but the carb does not have the correct vacuum port for the control valve.  The vacuum for the control valve is coming from a port at the base of the carb just before the intake manifold which probably helps to explain the really abrupt shifts from neutral to Low Range or reverse.  The 12 mm vacuum lines look to be mostly original as one of them is judiciously wrapped with electrical tape.  And will also have to replace at least one of the atf lines which is leaking from the coupling at the trans.  So will have a bunch of work to do to get it sorted. 

After extensive testing with the test light I figured out the following two things. 

1)  The car will start and will successfully shift and engage into all gears except for Dr 1 with or without the shift lever ground wire connected. 

2)  When shifting into Dr 1 the control valve will continuously fire engaging and disengaging the clutch resulting in the jerking. 

Was at a loss of what to do so I switched out the new (used) neutral start switch back to the one that came with the car and....... it's working again.  The car will now successfully switch into and drive in all gears without the continuous jerking in Dr 1 but it will still start up in any gear.  I have no idea why.

The best explanation that I Can come up with is that the gear selector shaft was somehow grounding out at the new (used) neutral start switch and causing the control valve to fire when any of the gears were selected except for Dr 1 in which case the control valve fired continuously.  When I swapped out the neutral start switch to the original one that came with the car it was no longer happening.  This may help to explain why the tip of the original neutral start switch is all hacked up.  I feel like I am grasping at straws on that last bit. 

Any thoughts?!

Breeze


volkenstein

#6
Breeze,
           Well and truly PO'd. So...
Down in the members step-by-step section - a complete write up on how to S-A a manual carb.
Next - what distributor? OO9 = P.O.S.  You should have a DVDA 113905205AH.
Then check your CV is adjusted to "normal" - 2 1/2 threads exposed.
You have some bizarre electrics. Do the NSS (believe you have) or bypass. Disconnect the gearstick, pull it out (take a photo of the plate orientation!!!!) and disassemble = check your contact points and spring.

Volkenstein
'71 RHD A-S Super - "Klaus"

olgunc

There are two main reasons for jerking. 1st is high idling speed. İt should be 950 RPM adjusted bu lamp. 2nd is high vaccum to the control valve. The thin hose from control valve should be tied to right top port on on your 34 pict 3 carb. it is possibly closed, so you need to open it. That port supplies correct vaccum above the butterfly in your carb. Lastly, arrange vaccum speed for shifting by half turning the screw on the control valve counter clock wise.

Breeze

Hi all and thanks for all of your knowledge and input.

It looks like I have quite a bit of work to do on my car to get it functioning properly.  It does not have the right DVDA distributor or the correct 34 pict 3.  I am going to drill out the correct vacuum port in the carb for the CV and tune the car as best as I can with the SVDA that's on it as it looks like it's pretty tough to find a decent used DVDA.  Will also rebuild the stick shift assembly and replace all vacuum hoses, and on and on.  I'm way up in Canada on Vancouver Island in the Pacific Northwest and have been getting parts from CIP 1 in Vancouver.  Fast friendly service from their crew but a rather limited selection of Autostick parts.  Does anyone know the best place to find the 12mm wire braided vacuum hose out this way?

Cheers, Breeze

volkenstein

Breeze,
          Tough Q on the hose - BMW or Mercedes Brake booster hose will fit. Also vac rated hydraulic hose - Parker-Hannefin IIRC.  You may need to try VW - Type 2 (Bus) brake booster hose.
SVDA? What is it? Numbers on body somewhere, probably fuel pump facing side.

HTH
Volkenstein
'71 RHD A-S Super - "Klaus"

Breeze

Thanks Volkenstine,
I found the 12 mm brake booster hose here at Lordco and it looks like it will do the trick. 
The distributor on the car is a 113 905 205 AJ.
Cheers
Breeze

volkenstein

Breeze,
           K, you have a manual DVDA and you scored some hose. Drill that carb as per the step-by-step. I wouldn't sweat the DVDA - far better than a 009 and the curve's are close enough (though different). Is your green hose (VAC RETARD) functional or it's plugged too?

Regards
Volkenstein
'71 RHD A-S Super - "Klaus"