- 1964-1967 SP400 Parts Images
- How to wire the Switch Pitch on a Buick Transmission
    - 400 auto codes
- BOP Bellhousings and Automatic Identification
Results 1 to 6 of 6

Thread: Switch Pitch Calibration

  1. #1
    Join Date
    Oct 2014
    Location
    Fort Worth
    Posts
    7
    My Feedback

    (0% Positive Feedback)
    Rep Power
    0

    Switch Pitch Calibration

    I've poured over tons of threads, read the manual and still have a few questions regarding this cockamamie Switch Pitch setup of my 67 Skylark. Just trying to get everything up and running the way it was originally intended.

    I have pulled the plunger switch off and cleaned it up and determined it's functioning correctly. I also know the idle micro switch is functioning.

    Firstly, I dropped the pan and strainer and find the stator solenoid wire just dangling with seemingly no solenoid. I can't even determine where should it be, because the shop manual photos are so poorly detailed. I don't see an orifice nor any threaded wells for fasteners. If indeed there isn't one, I would like to acquire one. Seems like it's impossible to find. Is there a source for them out there somewhere?
    The detent solenoid is there and functions as intended.

    Secondly, I have determined the idle micro switch should be open at idle and closed with the slightest throttle pressure applied. Is that correct? If so, I can't determine in what way the switch is actuated by the linkage. There is no cam or anything of that nature on the clevis linkage and I am unable to make the switch engage by any other method than just pressing it by hand. In others words, throttle applied does not engage, nor disengage the switch. I have attempted to adjust its position, as the manual stipulates, but as I stated, I don't see anything which should contact the switch.

    Thanks for reading!

  2. #2
    Join Date
    May 1999
    Location
    A, B
    Posts
    3,497
    My Feedback

    (0% Positive Feedback)
    Rep Power
    10
    I was messing with that about a year or so ago, but my idle switch was working properly. Looking at the manual, it appears that the switch rolls around the linkage varying the pressure on the "trigger". Examine the screws, they should be loose, and one should be in a long slot.

    The stator solenoid is the same as the detent solenoid. It is mounted on the inside of the pump. During assembly, you lower the pump into position and thread the wire into the main housing to be hooked up later when working on the valve body etc. If your wire has broken off of the solenoid, the only access will be to remove the transmission and pull the pump off the front.

    Maybe someone with more experience with chime in. Otherwise I will try and see what I can find tomorrow.


    WEBNOTE: When inserting an email in a posting, use the "smilie" @ so that web robots don't pick up your address and send you more junk mail!
    Members can be contacted by clicking on their "handle", but you are much better off to post to the thread!

  3. #3
    Join Date
    Aug 2015
    Location
    Oakland Ga
    Posts
    131
    My Feedback

    (0% Positive Feedback)
    Rep Power
    0
    At idle, the converter should be in high stall, off idle, low stall, then back to high stall at 60% and WOT, when the transmission kicks down. The idle switch and plunger switch makes that happen. Here are 2 pictures of a pristine set up. And yes, the solenoid is mounted inside the pump.
    Attached Images Attached Images
    Larry

    1970 GS455 Stage1 Race weight 4025 lbs.
    TSP 470, 602 HP, 589 TQ
    MT headers, Gear Vendors Overdrive
    Best E.T. 11.54 Best MPH, 116.06
    1998 Riviera SC3800

  4. #4
    Join Date
    May 1999
    Location
    A, B
    Posts
    3,497
    My Feedback

    (0% Positive Feedback)
    Rep Power
    10
    Glad Larry uploaded that, the one on my '66 Riv is a little different.
    66-idle-detent.png


    WEBNOTE: When inserting an email in a posting, use the "smilie" @ so that web robots don't pick up your address and send you more junk mail!
    Members can be contacted by clicking on their "handle", but you are much better off to post to the thread!

  5. #5
    Join Date
    Oct 2014
    Location
    Fort Worth
    Posts
    7
    My Feedback

    (0% Positive Feedback)
    Rep Power
    0
    Thank you both. Great information. I actually read the service manual, instead of skim, and I see exactly wherein is some mention of the solenoid - in the pump!

    So, guess who's dropping the trans for a rebuild. Oh, joy!
    I'm betting I'll go back with a different arrangement to actuate the solenoid than the factory linkage.

    There's a 100 percent chance I'll be dropping in here for some additional insight as my project progresses.

    In fact - I need some already.

    I dropped the drive shaft with the intent to replace u joints and found the slip yoke is not in great shape. It's a 27 spline and it measures 5" in length. I've found a few new units available online but they measure 5.4 to 5.5 inches. Surely I'm not measuring incorrectly...

    If a BOP TH350 is interchangeable with an ST300, I would assume one of these would be easy to find! Anybody know a good source and which exactly I need?

  6. #6
    Join Date
    May 1999
    Location
    A, B
    Posts
    3,497
    My Feedback

    (0% Positive Feedback)
    Rep Power
    10
    There are some alternate wiring information in the reference section, the link is at the top of this page.


    WEBNOTE: When inserting an email in a posting, use the "smilie" @ so that web robots don't pick up your address and send you more junk mail!
    Members can be contacted by clicking on their "handle", but you are much better off to post to the thread!

Similar Threads

  1. 67 Gs 400 T-400 Switch Pitch
    By Steve N 67 GS in forum Transmissions and Drivelines...
    Replies: 2
    Last Post: 01-02-2017, 08:04 AM
  2. Wanted to buy switch pitch convertor linkage control switch, 66 Lesaber, TH400.
    By G Ride in forum Transmissions and Drivelines...
    Replies: 1
    Last Post: 01-02-2017, 08:01 AM
  3. switch pitch
    By soberarmy in forum Transmissions and Drivelines...
    Replies: 7
    Last Post: 05-18-2009, 01:42 PM
  4. RE-toggle switch for switch pitch
    By bebop138 in forum Transmissions and Drivelines...
    Replies: 0
    Last Post: 02-21-2006, 07:51 PM
  5. Switch pitch 400
    By Janitor in forum Transmissions and Drivelines...
    Replies: 1
    Last Post: 01-14-2002, 06:48 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
TeamBuick.com Privacy Policy