73 FJ40 with clutch problems

Discussion in '40- & 55-Series Tech' started by RMC73FJ40, Aug 15, 2010.

  1. RMC73FJ40

    RMC73FJ40

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    Location:
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    I'll start with this is my son's 73 FJ40 with a SBC in it that we rebuilt and put a new clutch in in May 09. It's been fine up until about 3 weeks ago.

    It wouldn't go into 1st or reverse at a stop. We thought it was the slave and replaced it. Today I replaced the master and no improvement.

    It's got a 350 running a Chevy bell housing with a Downer adapter to mate up the 3 speed. When we rebuilt it we used a Zoom clutch kit from Summit.....clutch, pressure plate, pilot bearing and throw out bearing. The master and slave are Toyota.

    The slave and master seem to be giving enough movement, but I still get awful grinding when I try to put in gear.

    Any idea where to start? I hope I can keep from pulling tranny...especially now that my son is off at college.

    Here's a pic of the clutch arm....I have no idea if its original or not: (I have tried slave rod in both holes)
    IMG00216-20100815-1627.jpg
     
  2. RMC73FJ40

    RMC73FJ40

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    I thought about this last night and I think I'm going to adjust the mount so that it's about 1/2 inch closer to the clutch arm and go from there. Seems like the slave rod was always near the end of its adjustment anyway.

    If someone could identify the clutch arm it would be appreciated.
     
  3. chevyfj40lc

    chevyfj40lc

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    I had the same problem, the clutch worked for one month .the problem is the hydraulics of toyota they do not have sufficient travel for the chevy pressure plate .there is a pressure plate does not nead much travel and is a LOW PROFILE FINGERS. I change mine and not had any problems .part#CA5473

    This clutch cover has a diameter of 11.0 inches.
     
    Last edited: Aug 17, 2010
  4. chevyfj40lc

    chevyfj40lc

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  5. Pinion

    Pinion

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    Check to see if the adjustment rod was torqued correctly last year. If it wasnt locked down properly, it will eventually work its way down the thread and wont disengage the tranny as well.

    Also, I'd just check the clutch to see if your son hasn't run through it yet.
     
  6. RMC73FJ40

    RMC73FJ40

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    I'm still working on it. I made a longer slave rod to clutch fork and that didn't change anything.

    I did go do some research on the clutch kit I bought and using the models and numbers provided in that other link:

    http://forum.ih8mud.com/40-55-series-tech/47498-clutch-aa-bellhousing.html

    By cross referencing the makes and model there with Rock Auto kit numbers it looks like I ordered the correct kit from Summit...MU5505-1. The picture for the '72 Chevy Blazer clutch fork looks like mine too.

    So I'll do a little more digging to see if maybe the clutch fork has become disconnected from the throwout bearing. (I didn't think that could happen)

    I have noticed the clutch pedal pressure need to move the clutch fork is very low with new master and slave. It isn't low enough at fork for me to move with my hands or anything like that.

    I guess this has been a good thing....it gives me something to do while he's off at college.

    Any other ideas would be greatly appreciated.
     
  7. RMC73FJ40

    RMC73FJ40

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    Thought I'd update the thread.

    My problem ended up being the clutch plate itself. When my son pulled off the pressure plate 5 pieces of steel dropped out. One we removed the clutch the metal around the transmission input shaft was broken in 5 spots on the flywheel side of the clutch plate.

    Unfortunately.......while putting everything back together I broke the bell housing trying to use the mounting bolts to pull everything together.

    I'd love to know the secret to getting everything to slide back together nicely!
     
  8. KRC73

    KRC73

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    Here are some pictures of the carnage
    Photo0235.jpg Photo0236.jpg Photo0238.jpg
     
  9. pbgbottle

    pbgbottle Forum Lifer SILVER Star

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    can i see a pic of the other side of the pressure plate ,the low profile fingers .

    as for the chevy clutch fork the hole closest to the bellhousing gives it a bit more travel

    :cheers:
     
  10. KRC73

    KRC73

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    the one we used that helped with the destruction of that clutch disk was the non low profile fingers on the pressure plate, that clutch disk was only a year old and had 5000 miles on it or less
     

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