|
|
|
Your donations help keep this valuable resource free and growing. Thank you.
|
Borg warner M 12 |
Post Reply 
|
| Author | |
firesnow 
AMC Fan 
Joined: Oct/10/2017 Location: Usa Status: Offline Points: 3 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: Borg warner M 12Posted: Oct/11/2017 at 12:11pm |
|
Hello all, I'm new to the forum but have been a fan for a couple of years. I'm restoring a 1968 AMX, factory 390 automatic. The M12 shifts to 2nd in the first ten feet of travel then shifts to 3rd at about 20mph. In the process of
changing fluid and checking for damage, I somehow LOST the modulator valve pin! Can any one give me the exact length of that pin so I can fabricate a new one?? Thanks |
|
 |
|
|
tufcj
Supporter of TheAMCForum 
Supporter of TheAMCForum Joined: Jul/10/2007 Location: Watkins, CO Status: Offline Points: 4097 |
Post Options
Thanks(0)
Quote Reply
Posted: Oct/11/2017 at 3:56pm |
|
There were 2 different lengths depending on the style/vintage of the modulator.
Edit: Did a little research. The rod is 2.944" for the small modulator, 3.444" for the bigger modulator. Bob tufcj Edited by tufcj - Oct/11/2017 at 4:03pm |
|
|
69 AMX
74 Javelin AMX 67 Rogue If you need a tool and don't buy it... you'll eventually pay for it... and not have it. Henry Ford |
|
|
|
|
firesnow
AMC Fan
Joined: Oct/10/2017 Location: Usa Status: Offline Points: 3 |
Post Options
Thanks(0)
Quote Reply
Posted: Oct/11/2017 at 6:48pm |
|
Thanks for the great info and a prompt reply. It appears I do have the large modulator valve. Approximately 5, inches long. Does anyone have a cross reference number for O'Reillys or AutoZone if I need to replace this valve? Thanks again for the help!
|
|
|
|
|
george w
Supporter of TheAMCForum
Joined: Jan/27/2013 Location: New Jersey Status: Offline Points: 2899 |
Post Options
Thanks(0)
Quote Reply
Posted: Oct/11/2017 at 6:57pm |
|
Hopefully you will not need to replace the modulator as they're scarce.
|
|
|
Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new.
|
|
|
|
|
amcenthusiast
AMC Addicted 
Joined: Jul/02/2012 Location: SW Atlanta GA Status: Offline Points: 1778 |
Post Options
Thanks(0)
Quote Reply
Posted: Oct/11/2017 at 11:18pm |
|
It'll upshift too quickly when the main line/throttle valve pressure is too low.
Running the trans like that will increase slippage and reduce durability. On your trans the vacuum modulator controls ('modulates') the throttle valve in the valve body. Your AMC TSM tells procedure for how to adjust the vacuum modulator 'by the book'. There are DIY ways to adjust your trans but familiarity breeds contempt so we will not have that discussion in public. |
|
|
443 XRV8 Gremlin YouTube video: https://www.youtube.com/watch?reload=9&v=2DmFOKRuzUc
XRV8 Race Parts website: http://amcramblermarlin.1colony.com/ |
|
|
|
|
Post Reply
|
|
Tweet
|
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Click for TheAMCForum Rules
Topic Options