• From: City of Roses
  • Registered: 2004-03-29
  • Posts: 793

Re: Trouble with my 1968 Semi Automatic Transmission

Hiya Darren,

The slamming into gear is a very common problem with AutoSticks.  Basically it has to do with three separate factors, control valve setting, servo/clutch arm adjustment, and idle speed.  All three need to be "in synch" for the clutch to shift smoothly.  The clutch arm adjustment (although a bit of a pain to get to) is pretty easy and setting the idle speed is not all that complicated.  However, most control valves have lost their ability to graduate the amount of vacuum is applied to the servo.  They are pretty much in an off and on mode due to the fact that their internals are worn.  To complicate matters, there are no rebuild kits for control valves any more.  So...............the best you can do for the slammin shifts is to set the clutch arm adjustment and the idle speed per manual standards and monkey around with the control valve adjust screw, hoping to find a sweet spot.

Your most recent observation of the servo in action tends to suggest that it is working.  That would also mean that everything upstream (the control valve, the shifter, and the vacuum lines and their connections) are working.  Question is whether or not they are working as designed - as in giving 100%.  As I mentioned last time, if they are, then you are looking at problems inside the bellhousing.  Not a happy prospect.

So....before looking at tearing into the bellhousing it would be a good idea to try adjusting that servo/clutch arm we already talked about.  If it is possible to, in effect, shorten that clutch arm by moving the adjusting nut/sleeve, it may be possible to restore the shifting action.  Let me know what you want to do - I can give you the step-by-step for doing an adjust on the clutch arm if you like.

Mike

1970 AS Bug

Mike

1970 AS Bug
1970 Bus - The Ruptured Duck
  • From: Portage, Indiana
  • Registered: 2004-03-27
  • Posts: 454

Re: Trouble with my 1968 Semi Automatic Transmission

It should not travel out as long as your hand is on the shifter. I'd say your next step would be to test the servo, lines, and vacuum tank and make sure they hold a vacuum. Sounds like something in that system may have a slow leak.

  • Registered: 2005-07-06
  • Posts: 11

Re: Trouble with my 1968 Semi Automatic Transmission

Sorry I have not replied earlier, I had not realized the topic spanned two pages.  I sure would like those instructions on adjusting the clutch servo.  I would love to give it a try.  I assume I want that rod to be able to travle farther into the unit?  Thanks

Darren

  • Registered: 2005-07-06
  • Posts: 11

Re: Trouble with my 1968 Semi Automatic Transmission

Just wondering if you guys are still out there?

Darren

  • From: City of Roses
  • Registered: 2004-03-29
  • Posts: 793

Re: Trouble with my 1968 Semi Automatic Transmission

Hiya Darren,

Sorry that I have not replied earlier, but I have been "out of the building" on a little jaunt to Central Oregon.  Vacation time and all..........

Do you still need/ want the instruction for the clutch servo adjust?

Mike

Mike

1970 AS Bug
1970 Bus - The Ruptured Duck
  • Registered: 2005-07-06
  • Posts: 11

Re: Trouble with my 1968 Semi Automatic Transmission

Absolutely Mike,

I was beginning to think you had given up on me!  I would love to get some instructions!  Thanks

Darren

  • Registered: 2005-08-24
  • Posts: 1

Re: Trouble with my 1968 Semi Automatic Transmission

It sounds like a vacuum leak to me.  I have been rebuilding a 72 and was told by a club member to check the clutch servo by pulling the vaacum line off, pushing in the rod by hand and then putting my finger over the tube the line attaches to.  This makes the rod stay in if the diaphram is good.  It worked for me, and mine works now that I have it running.  If it is bad then CIP1 has a kit to fix it for $29.95.   If it is good, look for leaks in the lines or in the cannister under the fender.

Emmett

23 Reply by J.R.

  • J.R.
  • Guest

Re: Trouble with my 1968 Semi Automatic Transmission

I was just reading this and it sounds almost like the problem I had with the 70 I bought for my father inlaw . The person I bought it from said he down shifted and it would not go into any gear and he was told by a shop it needed a new trans . I bought it and was going to put the body on a standard pan. when I was playing with it it made the servo work but no luck putting it into gear so I was going to go ahead and  pull the body pulled the rear seat to get to the body bolts removed the cover over the shift coupler and there it was..the shift coupler had come loose on the front of the trans . tightened it and it is still working fine a year latter anyway maybe yours could be this simple . hope this helps

  J.R.