TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > Transmission & Drivetrain
  New Posts New Posts RSS Feed - model 20 answers
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

model 20 answers

 Post Reply Post Reply Page  <1 202122
Author
Message
rwtylla View Drop Down
AMC Apprentice
AMC Apprentice
Avatar

Joined: Mar/11/2016
Location: Dolores
Status: Offline
Points: 38
Post Options Post Options   Thanks (0) Thanks(0)   Quote rwtylla Quote  Post ReplyReply Direct Link To This Post Posted: Sep/22/2023 at 11:18am
I just rebuilt my model 20 in a 68 amx. new pinion and ring gear bearings clutch plates, ect. I was very happy with the foot print on the ring gear, I had perfect ovals on both sides in the center of the ring gear.
my problem is it howls under a load. I really dont know what went wrong.  250 lbs of torque on the crush washer, loaded the side bearings to .008 clearence, 0075 backlash on the ring gear, axle end play is .005
any thoughts or ideas would be helpful
thanks
ROB
Back to Top
1970390amx View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/11/2008
Location: colorado
Status: Offline
Points: 3311
Post Options Post Options   Thanks (0) Thanks(0)   Quote 1970390amx Quote  Post ReplyReply Direct Link To This Post Posted: Sep/22/2023 at 2:11pm
Originally posted by rwtylla rwtylla wrote:

I just rebuilt my model 20 in a 68 amx. new pinion and ring gear bearings clutch plates, ect. I was very happy with the foot print on the ring gear, I had perfect ovals on both sides in the center of the ring gear.
my problem is it howls under a load. I really dont know what went wrong.  250 lbs of torque on the crush washer, loaded the side bearings to .008 clearence, 0075 backlash on the ring gear, axle end play is .005
any thoughts or ideas would be helpful
thanks
ROB

The spec you state on the crush washer sounds strange. It should be a very low torque measured by what it takes to rotate the pinion. Like maybe 20 inch lbs.
1970 390 4speed Bittersweet shadow mask AMX
1970 Amx missing most everything, or in a box
Back to Top
WARBED View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Feb/12/2011
Location: Edinburg TX
Status: Offline
Points: 1677
Post Options Post Options   Thanks (0) Thanks(0)   Quote WARBED Quote  Post ReplyReply Direct Link To This Post Posted: Sep/22/2023 at 11:01pm
Torque on the pinion nut and crush sleeve is not a set torque value. don't know where you got 250 ftlbs you need to use a dial inch pound torque wrench. The free torque on the pinion nut should be around 22 INCH POUNDS.. don't quote me on that number. So basically, you tighten the pinion nut untill there is no slack then measure with the inch pound meter till you have the desired torque value. pinion should spin without the ring gear installed with slight resistance. You probably over torqued the assy and need to totally disassemble replace pinion bearings and start over. remember inch pounds not Foot pounds. again once tightened the pinion nut should be able to spin with around 22-inch pounds. so it takes small steps untill you get the desired settings.
59 American 2dr S/W. 70 390 AMX. 70 232 javelin. Kelvinator fridge ice cold beer storage.
Back to Top
WARBED View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Feb/12/2011
Location: Edinburg TX
Status: Offline
Points: 1677
Post Options Post Options   Thanks (0) Thanks(0)   Quote WARBED Quote  Post ReplyReply Direct Link To This Post Posted: Sep/22/2023 at 11:09pm
Do not over tighten the pinion nut. If the rotating torque figure is exceeded, a new collapsible pinion spacer sleeve must be installed. Do not loosen and retighten the nut.
59 American 2dr S/W. 70 390 AMX. 70 232 javelin. Kelvinator fridge ice cold beer storage.
Back to Top
tufcj View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar
Supporter of TheAMCForum

Joined: Jul/10/2007
Location: Watkins, CO
Status: Offline
Points: 4065
Post Options Post Options   Thanks (0) Thanks(0)   Quote tufcj Quote  Post ReplyReply Direct Link To This Post Posted: Sep/23/2023 at 8:39am
Also need some clarification on the carrier bearings.  They should have a +.008" preload, meaning the bearing/shim pack should be WIDER than the gap in the housing.  Otherwise the carrier will move and the tooth contact pattern will change.

Got any pics of the contact pattern, particularly the drive side?  Your "oval" should cover the vast amount of the tooth, not just the center. 

If you go to Ratech, https://ratechmfg.com/  They have a crush sleeve eliminator, which uses a spacer and shims, and is easier to get preload correct and it will stay put under hard use.

Bob
tufcj


Edited by tufcj - Sep/23/2023 at 8:45am
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
Back to Top
 Post Reply Post Reply Page  <1 202122
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.109 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or