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    Results 1 to 13 of 13
    1. #1
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278

      Clutch doesn't want to downshift when warm? TKO600

      Lately, my TKO600 doesn't like to downshift, and reverse is a real bear after I've driven the car for 15 minutes. It's fine cold, and it upshifts just fine. I have about 3000 miles on it now with no other issues. This just started about a month ago. Is it simply a matter of re-adjusting my mechanical clutch linkage?

      I guess my feeling was that as the clutch breaks in/wears, there would be more clearance, not less between the clutch and flywheel. But it acts like it's not releasing cleanly. And if so, why would a warm engine/tranny affect it? Is my flywheel expanding that much with heat? Or is my pilot bearing the culprit? I have a Pontiac, so I couldn't use a roller bearing, and am using a stock style brass bushing. My runout was dead on.

      Any thoughts?



      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.


    2. #2
      Join Date
      Sep 2006
      Location
      Henderson,NV
      Posts
      2,870
      Country Flag: United States
      How much pedal travel do you have befor the clutch starts to disengage?
      Todd

    3. #3
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278
      I haven't really paid attention lately. I'll check it on my way home from work. I set it around 1-1.5"...but that was done with me under the car witha feeler gauge and my wife moving the pedal...so that's a total crapshoot right there if you know what I mean. I've driven it all summer and haven't thought much about it until I started having issues with reverse at a recent car show, and now today at lunch I had some trouble getting into 1st at the stop light.

      I am leaving for CO tonight on vacation so I don't have time to get under the car with a feeler gauge, but I don't wanna sit and fret over it for the next week either! Argh! I'm hoping someone puts my mind at ease and can confirm that as a clutch wears, the adjustment rod needs to be lengthened, thus removing 'freeplay' in the pedal. Or rather, as the clutch wears, 'freeplay' will increase and the TOB will need to be adjusted closer to the clutch fingers via lengthening the adjustment rod. Is that correct?


      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.

    4. #4
      Join Date
      Sep 2006
      Location
      Henderson,NV
      Posts
      2,870
      Country Flag: United States
      You can check your pedal travel in the car with a tape measure. The only scenario I can think of is your pressure plate springs have lost a little tension making you push the pedal a little farther to disengage. I'm sure it's a simple adjustment.
      Todd

    5. #5
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278
      It's strange though to me that it's worse when the car is warm. I suppose the various parts involved expand with heat and require even more travel.


      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.

    6. #6
      Join Date
      Apr 2001
      Location
      The City of Fountains
      Posts
      15,971
      Country Flag: United States
      Quote Originally Posted by Josh69 View Post
      It's strange though to me that it's worse when the car is warm. I suppose the various parts involved expand with heat and require even more travel.
      This tells me that you need more airgap between the disk and flywheel. Check what it is now.

      Andrew
      1970 GTO Version 3.0
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    7. #7
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278
      I re-adjusted the clutch, everything seems to disengage fine now. There was a LOT of slop in the pedal, like 3"+ before it would engage the TOB.

      However, I have a new problem. I can't figure out why, but the pedal is 'sticking' at the top of the travel. I checked and it's not hanging up on the linkage anywhere. I can't imagine the TOB has worn a groove into the input shaft, but that's what it feels like. Once I'm past that sticking point, it works fine.


      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.

    8. #8
      Join Date
      Sep 2006
      Location
      Henderson,NV
      Posts
      2,870
      Country Flag: United States
      Is your z bar and pedal linkage lubricated?
      Todd

    9. #9
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278
      Looks like it is the linkage hanging up where the adjustment rod sits in the cup of the release arm. All the parts were new, and the metal on the rod is soft. Looks like someone used it for a punch, LOL. It's mushroomed on the end to a degree. I guess it's a matter of wearing itself in to work freely in the cup/receiver divot anytime it's rotated for adjustment.

      I adjusted the clutch this weekend to give the best pedal feel and what I thought was adequate air gap, but after driving it for 2 hours, it got to the point I couldn't shift well anymore.

      I'll re-adjust the clutch for proper air gap and worry less about the pedal feel. I guess it's the nature of the beast with a mechanical linkage. Now I see why guys go with hydraulic.


      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.

    10. #10
      Join Date
      Apr 2005
      Location
      USA
      Posts
      4,462
      Country Flag: United States
      Are you using the correct fluid ???
      You should be using Synchromesh ...
      TKO's are a little tempermental about being hard to shift.
      It's partly because of the 3 internal shift rails and the lugs that attach the main shifter rail to them.
      There's several pieces in there that cause a bit of stiffness ( binding)in the shifting mechanism.
      It is important that you use the correct fluid and have enough clutch gap when the cluth pedal is pushed all the way down.
      The clutch must be fully disengaged from the flywheel ( input shaft of the trans fully unloaded ) or the TKO's are hard to shift.
      Also , you must not have more than .005" lateral runout on the bellhousing or you will get side loading of the input shaft of the trans and it will hang between gears.( the input shaft of the trans is loaded )

      The TKO is an awesome trans , It will hold tons of power.
      But , it has tight tolerances and and a complex shift-rail mechanism.

      Also , make sure you have the correct clutch fork.
      The first-gen f-bodies use a different fork than the 2nd-gen and up.

      It sounds like you just need to re-adjust your clutch linkage.
      Jeff Tate
      U.S.A.
      "The best thing about participating in these events is that you get to hang out with a group of intelligent like minded people who live to achieve things in their lives. You won't find a lazy, mean, or dumb bone in their bodies." Bret Voelkel, RideTech

    11. #11
      Join Date
      Aug 2004
      Location
      Rockford, MN
      Posts
      278
      Yeah, I have GM Synchromesh, bought it from the local dealer, I was very careful to follow the instructions. My bellhousing alignment is good, no more than .003 IIRC. I haven't had any trouble for close to 3K miles, so I think it all comes down to adjustment.

      Part of my issue is the spring return for the clutch arm. I cannot get a reman'd firebird return spring or extension rod, though I do have the correct frame bracket to use if I find one. I am currently using the Camaro spring and extension arm and running that to a bracket I made off a header bolt. It worked well for awhile, but now it's contributing to the crappy pedal feel, as the spring is side loading the clutch fork, so when I dialed out the ratchety feel towards the end of the stroke, I also reduced my air gap. It was a half dozen of one, 6 of the other type deal. It got cold here fast, so I haven't had a chance to drive it again with a proper air gap setting. I hope to this coming Sunday....of course we got 4" of snow the other night, so who knows.


      1969 Firebird, Black, Parchment Arizen interior, Poncho 383 (4" crank), Kauffman heads, TKO600, Moser 12 bolt, Wilwoods, DSE, Speed Tech, Koni, Hotchkis, GW, 18" TTI's, VA Gen IV, etc.

    12. #12
      Join Date
      Sep 2006
      Location
      Henderson,NV
      Posts
      2,870
      Country Flag: United States
      If you have a blow proof bellhousing you can use on of those bolts to attach a bracket and a heavier spring. That's what I did and so far so good.
      Todd

    13. #13
      Join Date
      Apr 2005
      Location
      USA
      Posts
      4,462
      Country Flag: United States
      I used the stock / reproduction return spring and the LONG , skinny wire rod that attaches to it.
      The long skinny, wire rod goes all the way up to a little hole in the rear of the motor mount bracket ( where it bolts to the crossmember).
      This gives a pretty good clutch feel.
      On stock cars , this wire rod runs straight from the clutch arm to the motor mount bracket ( with no interference ).
      If you have headers , they will be right in the path of the rod.
      I hose-clamped the rod to my steering box to pull it over off the headers.
      It seems to work great.
      Jeff Tate
      U.S.A.
      "The best thing about participating in these events is that you get to hang out with a group of intelligent like minded people who live to achieve things in their lives. You won't find a lazy, mean, or dumb bone in their bodies." Bret Voelkel, RideTech





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