Disengaged clutch puts load on motor..

Discussion in 'Technical' started by garrettmuir1227, Sep 3, 2015.

  1. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    okay guys so heres the issue.
    my mav has a 302 with T5 5-speed, using the cable clutch conversion thats very popular on these cars. I'm using an ACT street performance clutch (the yellow one) i have found that when i depress the clutch pedal the idle will drop about 150rpm and if i rev it it'll choke out and die. gear selection doesn't play a part in it. obviously that indicates an added load on the motor.... has anyone else had this issue? are there key places that can cause this issue?
     
  2. dyent

    dyent Member

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    how many miles do you have on cable/clutch assembly? obvious things to check first, cable adjustment, as it will stretch over time and might not be totally disengaging, any visible signs of binding, possibly throwout bearing could be going.......did you perform the install yourself?
    David
     
  3. Krazy Comet

    Krazy Comet Tom

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    The only thing that can be happening is the throw out bearing is binding, OR maybe the thrust bearing in engine is worn to the point the crank counterweights are rubbing the main bearing saddles(happened to the 5.0 in my T-Bird)...
     
  4. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    Yeah did it all myself. Easily less then 200 miles on everything... Sounds like if it's not a cable issue I might have to pull this trans out... Darn lol... I'll check the easy stuff when I get home today.
     
  5. Krazy Comet

    Krazy Comet Tom

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    So anyone wanna explain how a stretched cable can cause this problem????

    If it were stretched and not disengaging, symptom won't be ANY different than partially depressing clutch.. You'd have trouble shifting in to, or from gear to gear(if even possible), but engine RPMs should not be effected...
     
  6. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    I see that but the car drives fine it has no shifting issues so it's deffinitly disengaging all the way... The more I think the more the throw out bearing or pilot bearing sound like issues
     
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  7. Krazy Comet

    Krazy Comet Tom

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    Well while we have 'em out on the bar comparing lengths, so have I but usually didn't have a tach... Drove a '68 E-100 van from Portsmouth to Va Beach, not once but twice with out clutch(linkage broke, yes twice)..., Even stopped and paid toll at the tunnel(automated these days wouldn't have to stop)... While rolling up to toll booth, slip it in neutral, cut engine and when stopped pull it back into 1st, pay toll, start engine and off it went... Had to stop for a few lights so did same...

    I taught the daughters how to shift without clutch as well(T-5 are easy if you know what you're doing)..
     
  8. Bryant

    Bryant forgot more than learned

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    im suspecting the worn thrust bearing in the engine also.
    try moving the balancer forward and backwards in the engine. it shouldnt have any perceivable movement.
     
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  9. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    Oh i sure hope it isn't the thrust bearing... I'll take a look at that later this morning. I don't think my half asleep self will give a good diagnosis:sleep:
     
  10. Krazy Comet

    Krazy Comet Tom

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    Yep mine had a nice clunk when pushing or prying on front pulley, had almost 100" clearance... The the rods had been pushed back and forth till side clearance was between .030 & .035"(still had great oil pressure though)... Crank was trash, thrust surface worn probably .040"...
     
  11. dyent

    dyent Member

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    Hopefully it is not the thrust bearing, you mentioned with only 200 miles on the install, could just be something else, perhaps a miss match of parts. What did you have before the T5 conversion, what about your motor, how many miles on that, was it rebuilt or still original......unfortunate thing with conversions, unless all the correct parts and all clearances checked, things can go wrong. I've even heard of swaps where the T5's longer input shaft (compared to Toploader) was pushing against the crank, which caused the thrust bearing to wear, this was because no adapter plate was used to compensate for the longer T5 input. Not to say this is in your case, but more of an example of what can go wr0ng in swaps.
    Keep us posted, fingers crossed that nothing too serious, good luck!
    David

    on a side note, was just talking to Billy at McLeod Racing and this same conversation came up too!
    They are coming out with their 5 speed tranny and he mentioned that it will be based on the shorter input length, like the toploader and not the longer T5 from 86-95 Mustang......
     
    Last edited: Sep 4, 2015
  12. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    uh oh... i had this problem with this conversion... i fixed it now but at first it ran shortly with it like that... never drove it but i did run it (with a lot of noise)
     
  13. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    Update: thrust bearing is good, no play at all in crank assembly. Next I guess I need to pull the trans... Yay:(
     
  14. dyent

    dyent Member

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    great news that your thrust bearing is OK, better to workout the bugs on the conversion than to rebuild the bottom end!
    what did you do to fix the initial problem with your conversion? did you use adapter plate or change the bellhousing? I know it is difficult, but before you pull the tranny, if you can somehow take a look through the hole where the fork passes in the bellhousing, see if anything is missaligned, how the throwout bearing sits on the pressure plate fingers, is it making proper contact with the fingers. In the old days, I used a mirror/flashlight to view, nowadays can get cheap inspection cameras on 3' flexible line, those are great!
    Then after the tranny is removed, double check that you do have enough clearance that your input snout is not bottoming out in the pilot bearing/crank. May take sometime measuring and calculating, but you want to rule out any problem with this once and for all.
    Good luck and hope your problem is something simple to correct.
    David
     
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  15. garrettmuir1227

    garrettmuir1227 (Almost) Certified to Work on Your Porsche

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    Hmmm.... You are talking about the actual input shaft?? My problem was at the actual input shaft housing. It was grinding on my clutch disk... Never checked the input shaft itself the clearances seemed good.. But I'll check it just to keep my mind at ease. Would using modeling clay like they do to test valve clearance work?
     

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