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Thread: Volvo clutch brake adjust??

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    xzostd1 is offline Member
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    Default Volvo clutch brake adjust??

    I'am looking for help with adjusting the clutch brake on my 1 million mile 2001 Volvo 770 Cummins N14 with Meritor 10. The clutch was replaced at 750k. I did a search and found some info from Bob H but need more info.
    I have done clutch work on cars and light trucks but have never worked on a heavy truck clutch.
    Thanks BIll

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  3. #2
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    assuming it's an easy-pedal clutch;... if it has hydraulic linkage, the only difference is that the free travel at the release bearing is nil (the final adjustment for mechanical linkage is 1/8")
    Bob H

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    xzostd1 is offline Member
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    Quote Originally Posted by bob h
    assuming it's an easy-pedal clutch;... if it has hydraulic linkage, the only difference is that the free travel at the release bearing is nil (the final adjustment for mechanical linkage is 1/8")
    I'll be under it tomorrow and will find out if I need more info
    Bill

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    I just finished replacing my clutch brake. Not alot of fun! First I split it into pieces with a air chisel and then used careful applications of my torch and chisel to remove the pieces, and installed the two piece. I now have a working clutch brake.
    The clutch is a Eaton-Fuller. There is a single bolt with a arrow pointing in a clockwise direction. Do I remove this bolt to adjust the disc or is this the adjustment?
    Bill

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    Quote Originally Posted by xzostd1
    I just finished replacing my clutch brake. Not alot of fun! First I split it into pieces with a air chisel and then used careful applications of my torch and chisel to remove the pieces, and installed the two piece. I now have a working clutch brake.
    The clutch is a Eaton-Fuller. There is a single bolt with a arrow pointing in a clockwise direction. Do I remove this bolt to adjust the disc or is this the adjustment?
    Bill
    it is the adjustment... use a 5/8 socket to push the bolt in and hold it, rotate clockwise to tighten the adjust, ccw to back it off... the bolt will only turn if the clutch is released

    careful with that clutch brake, it is not torque limiting
    Bob H

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    it is the adjustment... use a 5/8 socket to push the bolt in and hold it, rotate clockwise to tighten the adjust, ccw to back it off... the bolt will only turn if the clutch is released
    Bob, didn't you mean turn it clockwise to loosen the adj. (give more free pedal), and CCW to "tighten" the adj. (give less free pedal) ???
    If you can't shift it smoothly, you shouldn't be driving it.

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    xzostd1 is offline Member
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    Thanks for the replies....I'll be underneath, "adjusting" ...Fri. morning
    Bill

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    xzostd1 is offline Member
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    New clutch brake installed and properly adjusted. (I'am pretty sure)
    Thanks again for great advice!
    Bill
    Landstar Driver

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    Quote Originally Posted by Splitshifter
    it is the adjustment... use a 5/8 socket to push the bolt in and hold it, rotate clockwise to tighten the adjust, ccw to back it off... the bolt will only turn if the clutch is released
    Bob, didn't you mean turn it clockwise to loosen the adj. (give more free pedal), and CCW to "tighten" the adj. (give less free pedal) ???

    clockwise rotation moves the pressure plate closer to the flywheel... this adds pedal free travel
    Bob H

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    Quote Originally Posted by bob h
    Quote Originally Posted by Splitshifter
    it is the adjustment... use a 5/8 socket to push the bolt in and hold it, rotate clockwise to tighten the adjust, ccw to back it off... the bolt will only turn if the clutch is released
    Bob, didn't you mean turn it clockwise to loosen the adj. (give more free pedal), and CCW to "tighten" the adj. (give less free pedal) ???

    clockwise rotation moves the pressure plate closer to the flywheel... this adds pedal free travel
    Yes, that is what I call "loosening" the adjustment, because if the clutch adjustment is "tight",(no free pedal travel) it needs to be loosened by turning the adjuster clockwise, therefore moving the pressure plate closer to the discs which results in the release bearing moving rearward, away from the release fork, giving more free travel at the pedal before the fork contacts the release bearing.

    This internal adjustment has no effect on clutch brake squeeze however.

    The way I do it is to set up the external linkage first, to get the proper clutch brake squeeze with the pedal slightly off the floor, then once that is set, I adjust the adjuster on the pressure plate to give the 1/8 clearance between the release bearing and the fork, and take note of how much free travel the clutch pedal has at this point.

    On subsequent adjustments I can then just turn the adjuster to regain the previously noted amount of free pedal, resulting in the 1/8 in. clearance automatically.
    If you can't shift it smoothly, you shouldn't be driving it.

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    Quote Originally Posted by Splitshifter
    Quote Originally Posted by bob h
    Quote Originally Posted by Splitshifter
    it is the adjustment... use a 5/8 socket to push the bolt in and hold it, rotate clockwise to tighten the adjust, ccw to back it off... the bolt will only turn if the clutch is released
    Bob, didn't you mean turn it clockwise to loosen the adj. (give more free pedal), and CCW to "tighten" the adj. (give less free pedal) ???

    clockwise rotation moves the pressure plate closer to the flywheel... this adds pedal free travel
    Yes, that is what I call "loosening" the adjustment, because if the clutch adjustment is "tight",(no free pedal travel) it needs to be loosened by turning the adjuster clockwise, therefore moving the pressure plate closer to the discs which results in the release bearing moving rearward, away from the release fork, giving more free travel at the pedal before the fork contacts the release bearing.

    This internal adjustment has no effect on clutch brake squeeze however.

    The way I do it is to set up the external linkage first, to get the proper clutch brake squeeze with the pedal slightly off the floor, then once that is set, I adjust the adjuster on the pressure plate to give the 1/8 clearance between the release bearing and the fork, and take note of how much free travel the clutch pedal has at this point.

    On subsequent adjustments I can then just turn the adjuster to regain the previously noted amount of free pedal, resulting in the 1/8 in. clearance automatically.


    Where did that procedure come from? I have never heard of someone adjusting the external adjustment first. Not that it won't work, I'm certain that it will... BUT, what if the linkage was ok before you messed with it?


    Here's an example; you install a brand new clutch on a h/d truck. you adjust the clutch to specs; internal adjustment for release travel (clutch), then external adjustment for free travel (linkage).

    6 months later the truck returns with little (or no) pedal free travel. If you crawl under that unit, and re-adjust your release travel to 1/2", you should NOT have to make an external adjustment at all ...

    ... the only reason we ever have to make external adjustment is because someone else has changed it before ... WHY? I assume it's because many techs dont' like to go under trucks, and have learned that they can give the driver the 1 1/2" of pedal free travel he's looking for without going under the truck...... laziness?, or lack of knowledge??


    Anyhow, back to the "tight" or "loose" adjustment; the clutch adjustment is all about the space between the pressure plate and flywheel, or a min 0.060" over air gap for the the discs to come free of the driving clutch. Tightening the clutch reduces that gap, loosening the clutch means widening that gap.

    External adjustment (free travel) is a clutch LINKAGE adjustment, and is a result of the internal adjustment --- you've said it yourself; you only do the external adjustment once, then you use the internal adjustment for each clutch adjustment following the initial. That's just 'my angle' ;0)
    Bob H

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    Bob, I didn't say anything about adjusting the external linkage every time.

    On subsequent adjustments I can then just turn the adjuster to regain the previously noted amount of free pedal, resulting in the 1/8 in. clearance automatically.
    What I meant is that on initial setup, I will adjust the external linkage if necessary to get the proper clutch brake squeeze, then do the internal adjustment to get the proper release bearing clearance and free travel.

    I've known since I was a kid that you don't adjust the pull type clutch for wear by adjusting the external linkage.

    bob h wrote:
    Here's an example; you install a brand new clutch on a h/d truck. you adjust the clutch to specs; internal adjustment for release travel (clutch), then external adjustment for free travel (linkage).
    But the point I'm trying to make is that if the linkage isn't adjusted to provide the proper clutch brake squeeze, then no amount of pressure plate adjusting is going to change that.
    If you can't shift it smoothly, you shouldn't be driving it.

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