C4 Tail shaft seal

Discussion in 'General Maverick/Comet' started by NWMO_Maverick, Dec 19, 2020.

  1. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    31B26AD9-A48A-4CBC-BA75-264A4E117DC3.jpeg 8AE19E65-7649-473F-8152-06E3135139B4.jpeg 5BE21A9F-1CC9-4A4A-85D0-73C3F450834D.jpeg


    Hey all,

    Failing front u-joint damaged the trans shaft seal and the pinion seal. I believe we have the correct replacements, but the trans seal is a little different than the rebuilder installed. The seal looks correct, but the dust cover is different. Is the pictured seal appropriate?

    I’m putting together a little press today with 1/2” plate, 7/16” all thread on the corners and using my bottle jack/sockets to replace the u-joints.

    I’m figuring to count rotations when we remove the pinion bolt and return to the same spot with a new crush sleeve. Will the old crush sleeve slide off or need carefully cut off?

    Thanks in advance for all the help. This is my son’s daily driver and we will more than likely be in the paved driveway. If we support the car to keep it from rolling, can we point downhill/jack the rear enough to keep from losing any/much trans fluid when we pull the driveshaft? I don’t recall a drain plug, but it’s been awhile.

    Chris & Gabe
     
  2. ike72com

    ike72com Member

    Joined:
    Sep 22, 2019
    Messages:
    343
    Likes Received:
    206
    Trophy Points:
    106
    Garage:
    1
    Location:
    Charleston SC
    Vehicle:
    1972 Comet, 70 mustang, F250 and F100
    If for a c4 just install. I,ve seen both type.

    As for loosing fluid? It is what it is.

    You inquiring about jacking downhill scares me!
     
    mojo and Ronald Hopkins like this.
  3. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    25,537
    Likes Received:
    2,238
    Trophy Points:
    828
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    you may want to check/replace the tailshaft bushing also.
     
  4. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    Thanks fellas,

    We will be safe, here is a pick of a “poor man’s” press we put together. Hopefully it will do the u-joint job.

    CBD292E8-F1C1-45A6-87DD-D9CC3FFEC5B9.jpeg
    Chris & Gabe
     
    rickyracer likes this.
  5. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    25,537
    Likes Received:
    2,238
    Trophy Points:
    828
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    did you get this project finished up?
     
  6. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    Hey all,

    We installed a new front seal, water pump, timing set etc. on the front of the engine and all went reasonably well. We got the rear driveshaft u-joint changed. We were leaking at the pinion shaft as well, so we renewed the seal and got things back together. We used a new bearing spacer and got 13+ revolutions of our 14+ revolutions counted when removing the pinion nut. I assume the “put it back in the same location” works when you reuse the old spacer? Is there a reasonable way to measure bearing “pre load” (rental tool from LAS)? I don’t have the manual for the Maverick, but my Toyota calls for pre-load torques and provides a max torque (174 ft-lbs) on the nut.

    The other difficulty encountered was a little movement on the two piece drive shaft balance weight. It got pushed a little out of square. I can get it back pretty close, but didn’t know if a machine shop could renue the rubber seal instead, it is definitely a little brittle.

    Chris & Gabe

    Thanks in advance!
     
    Last edited: Jan 31, 2021
  7. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    25,537
    Likes Received:
    2,238
    Trophy Points:
    828
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    "The other difficulty encountered was a little movement on the two piece drive shaft balance weight."
    if you are talking about the balancer ring ... you can just remove it.
     
  8. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    Hey all,

    We put a new bearing spacer in the rear. I don’t have a Maverick service manual. I assume I should tighten the nut on the pinion shaft and then check ft-lbs required to turn the shaft/axle? tires in the air (both, or is one good enough?) wheels off or on?

    If not tight enough, tighten the nut and check again.

    Chris & Gabe
     
  9. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    25,537
    Likes Received:
    2,238
    Trophy Points:
    828
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    my opinion ...
    you are looking at this all wrong...google...setting up ring gear.
     
  10. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    We had to remove the pinion nut, etc. so we could renew a leaking seal. I assume a complete tear down of the diff and setting all pre loads is not required. We have the original “crush” sleeve and marked the nut, so we could put it back exactly as it was. What have others done when they renew the pinion seal? TIA.

    chris & gabe
     
    Krazy Comet likes this.
  11. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    25,537
    Likes Received:
    2,238
    Trophy Points:
    828
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    I'll ask Harold today, he replaces a least 3-5 ring and pinion sets a week.
    how many miles on the car?
    yesterday he tore a 150 Ford truck down that had some special rear end under it. when he called about a bearing set...$300...:yup:
     
  12. BBMS18

    BBMS18 Member

    Joined:
    Aug 5, 2018
    Messages:
    748
    Likes Received:
    410
    Trophy Points:
    161
    Location:
    Grand Rapids, Michigan
    Vehicle:
    75 Comet
    If I remember correctly the crush sleeve is “crushed” to a specific torque # which give you the proper preload, it’s not a case of just putting the nut back on in the same position.
    If you look up “setting up ring gear” like Frank suggested you should find the information you seek.
     
  13. NWMO_Maverick

    NWMO_Maverick Member

    Joined:
    Oct 29, 2016
    Messages:
    140
    Likes Received:
    29
    Trophy Points:
    67
    Garage:
    1
    Location:
    Northwest MO
    Vehicle:
    1970 Maverick
    Thanks for the help,

    Odometer show 60k miles on the car. Based on condition/age, I expect it has 16ok miles on it, though 260k is possible.

    I did watch a video (as suggested) on setting up the rear differential. It appears to "set the diff up", they start with the entire third member in a vice, start with pinion shaft pre-load and then build from there. I find it highly unlikely that any time a pinion seal leaked, the shops would remove and do a complete tear down of the third member. That said, it was beneficial for me to understand the pre-load specs are to be measured without the rest of the diff providing drag.

    "If I remember correctly the crush sleeve is “crushed” to a specific torque # which give you the proper preload."

    As I understand it, if using a new "crush" sleeve (and setting bearing pre-load), it is installed and then torqued down to a number on the low side (?? ft-lbs). An in-lb torque wrench is then used to check the torque required to turn the pinion shaft. If it turns below the torque spec (again in-lbs on the pinion shaft), the pinion nut is tightened 5-8 ft-lbs and the shaft torque is checked again. This procedure continues until the desired torque is measured spinning the pinion shaft. Again, if I understand correctly, this is completed with the third member entirely apart and then you build from there. In addition, a max torque spec is provided for the pinion nut (170 ft-lbs on my little Toyota). If you reach max torque and still don't have the desired torque spec on the pinion shaft, I presume you start with a new "crush" sleeve and start the process again.

    The original "crush" sleeve slid off the pinion shaft as easily as the new one slid on, so it's not like the sleeve pinches the pinion shaft or anything (at least this one didn't). By using the original "crush" sleeve and setting the pinion nut back to the starting location, I believe it is reasonable to assume the bearing pre-load will very nearly match what it was prior to renewing the seal. The rear has not given us problems and sounded fine during operation, so we will likely get it back together and listen carefully for anything different. Thanks for the help.

    Chris & Gabe
     
    Last edited: Feb 3, 2021
  14. BBMS18

    BBMS18 Member

    Joined:
    Aug 5, 2018
    Messages:
    748
    Likes Received:
    410
    Trophy Points:
    161
    Location:
    Grand Rapids, Michigan
    Vehicle:
    75 Comet
    That’s how I would go about it with the addition of giving the nut a extra 1/4-1/2 turn to make sure it’s tight.(y)
     
  15. Krazy Comet

    Krazy Comet Tom Supporting Member

    Joined:
    Sep 13, 2012
    Messages:
    6,798
    Likes Received:
    1,696
    Trophy Points:
    521
    Garage:
    1
    Location:
    Chesapeake VA
    Vehicle:
    1972 Comet GT clone 306 . 1969 Fairlane Cobra 428CJ 1988 T-Bird awaiting 331 ..
    If gears are running quiet, without excessive backlash, no reason setting nut back to original position won't work. On noisy ones(howl) adding 1/8 to 1/4 turn often fixes them(otherwise tighten to orig position). In '80s I bought and sold transportation specials, ain't nuthin' I haven't tried at least once.
     
    71gold and stumanchu like this.

Share This Page