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Discussion Starter · #1 ·
You'd think I have this do

You'd think I have this down to a science by now...with 20 gleefull year of ownership with this car, but noooo.

Here's the problem. It all started when I totally disassembled, rebuilt, replaced, replated all of the clutch adjustment linkage arms and pieces...I reassemble components as I remember them to be...and adjusted the clutch as I have down sooo many times before (without a hitch).

Here's the procedure that used to work...
1) Disconnect clutch cable from fulcrum arm.
2) Set TO bearing to PP clearance at 2mm, using the horizon adjuster.
3) Reconnect clutch cable and adjust cable adjuster for 5-6mm centerline offset from the top clevis pin to the bottom one (verifying that the offet plate hole lines up with the fulcrum arm.

Voila, I should be done...

However, now when I do this...and set on the clutch pedal and release...there is now substantial play in the clutch cable under the car, and the fulcrm arm in not back (to its orginal adjusted position. Note that with slight hand force, I can pull the arm back to it's proper position...

I'm totally at a loss here...
All clutch components are new, including the flywheel. The TO bearing moves freely on the transaxle snout...and the clutch arm moves freely in the tranaxle...

What am I missing here?

Picture prior to depressing clutch-Adj. looks good


After clutch depressed and released-adj. off and slack in clutch cable

 
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Discussion Starter · #2 ·
David,

Did you remove the


David,

Did you remove the cable or just the linkage pieces?

From the photo it appears that the rod adjustment is all the way in, instead of all the way out as it would be in the case of a new clutch. Is that what I'm seeing? Have you tried lenghtening the adjuster?
 
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Discussion Starter · #3 ·
Another thing just occured to

Another thing just occured to me. It is possible to put the lever back on on the wrong spline of the cross shaft. Could this have happened?

In looking at the very last pic again, isn't the arm supposed to be striaght down with peddle pressure off?
 
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Discussion Starter · #4 ·
Just a thought: In the first

Just a thought: In the first picture, if one follows the long axis through the center of the spring, it continues to the left side of the adjusting rod pin below. In the second picture, the axis is seen to the right of the pin.

With the clutch fully depressed, the axis, I believe should move so that it goes through the center of the pin, and not to the right of it.....if it goes to the right of the pin, then releasing the pedal will allow the axis to stay to the right, as seen in the second picture.

Does this make sense?

Just my .02 cents!!!!!!1
 
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Discussion Starter · #5 ·
JR,
I did not remove the clut


JR,
I did not remove the clutch cable from the car...It does move freely and appears to be in good condition.

All the linkage pieces you see were removed...cleaned, rebuilt, etc.

"Is it possible I put the clutch release lever on the wrong spline...Absolutely. Although I marked the shaft (with magic marker), the solvent used for cleaning wiped it off. Clearly a brain dead moment!

My WSM shows that the clutch release arm should be at approx 45 degrees, when the TO bearing is just touching the PP. Hmmm, if I lenghten the adjuster rod as you suggest, the overall geometry will centainly change...I didn't realize that the adjustment arm should be "extended" so to speak with new clutch components. I'll give that a try in the am.

How does the adjustable pivot, on the overcenter spring pivot come into play...?

Lots of variables here, for sure...

Appreciate yout help!

Regards,
David
 
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Discussion Starter · #6 ·
Now for the solution: I may b

Now for the solution: I may be wrong, so please bear with me.....this is analytical fun!!!!!

Depress the clutch and verify that the axis does NOT go past the center of the pin, thus to the right of it.

If it does, and I assume so, then the lever arm attached to the fork shaft should be moved slightly upward, maybe a spline or two. OR, the adjuster rod should be adjusted so that it brings in the axis of the spring.....if it doesn't disturb the 2 mm space between the TO bearing and the clutch.
 
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Discussion Starter · #7 ·
Henry agree about the spring.

Henry agree about the spring.

From the pics it appears that if the adjuster is lenghtened, it will push the spring back into the over center position where it's supposed to be.

>> the solvent used for cleaning wiped it off. <<

I center punch them with a small sharp punch, dead center of the split.
 
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Discussion Starter · #8 ·
Oh, I love analytical fun...

Oh, I love analytical fun...

Although I am an EE with minor in Mechanical Engineering, geometry and I never got along. Who would of thought after all these years I'd actually need it?

I suspect you're on the right path...If the adjuster rod length is changed and/or if I move the splined arm position, the TO bearing clearance will be affected. They both interact with one another...

I'll get someone over here tomorrow to photograph the postion of the arms with the clutch depressed.

Thanks for your input!

David
 
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Discussion Starter · #9 ·
JRV: I think the adjuster sho

JRV: I think the adjuster should be shortened, and not lengthened. By lengthening, it will push the axis farther to the right......I believe, we want the axis to stay to the left....thus shortening.
 
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Discussion Starter · #10 ·
Henry,

to me it looks like


Henry,

to me it looks like to the right (in the pic) is the direction the spring needs to go. The rod looks to be at it's shortest already, or close to it. I believe the spring goes from overcenter on one side to overcenter on the other as it travels it's arc.

But sometmes I get this stuff backwards unless it's up close and personel..;-).

Could be two problems, off a notch and wrong rod lenght?
 
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Discussion Starter · #11 ·
David: More analytical fun...

David: More analytical fun......how's this? In both pictures it appears that the inward spring tension is zero. Bring in the adjusting rod, by shortening it as much as possible, to where the spring still has zero tension......any more, and it will move the fork shaft.....that we don't want.

Then check the axis, with the clutch depressed. If still to the right, then you will have to move the fork shaft upwards......and then re-do the adjusting rod.

I notice in your picture, that there is a punch mark on the shaft lever, but not on the shaft itself.

On my Boxer, there was a punch mark on the shaft, which aligned with the opening in the lever. This appeared to be from the factory......since, even with the new clutch, the position of the alignment marks remained the same.
 
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Discussion Starter · #12 ·
JRV: I see your point......mi

JRV: I see your point......mine was made with the assumption that David is correct when he stated the first picture as being accurate.

David: Are you correct with the first picture?
 
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Discussion Starter · #13 ·
Henry,

Here's my premis


Henry,

Here's my premise. If I'm understanding this correctly.

Cable is to slack...yet arm & TO are forward touching PP...therefore the rear most arm (fulcrun lever)must move towards the rear (right)to remove cable slack. To achieve this the adjuster rod would need to be lenghtened until taught, then backed off for freeplay, then as the disc/s wear, allowing the PP to extend rearward, the rod is shortened to provide freeplay.

?????
 
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Discussion Starter · #14 ·
To summarize a bit...
In the


To summarize a bit...
In the first picture, the TO bearing to PP clearance is correct...and there is approx .5" of freeplay in the clutch pedal. When the clutch is first depressed, all feels perfect.

In the second picture, this is what the clutch linkage looks like after the inital clutch depression...and there is now all sorts of clutch cable hanging loose beneath the car...and the TO is now resting on the PP (no clearance).

With ease I can pull back on the fulcrum arm and all is then back to correct clearance and slack.
 
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Discussion Starter · #15 ·
David: You are "pulling&#

David: You are "pulling" back on the fulcrum arm......I am assuming you are pulling back on the bottom portion, where the cable attaches to, below it's swivel point.....thus, bringing the top portion "in", closer to the engine......this would move the TO bearing "away" from the clutch.

Therefore, the bottom portion has to be moved farther "back".......hence keeping the axis to the left. This would take the extra slack out of the cable.

The bottom line.......keep the axis to the left!!!!!
 
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Discussion Starter · #17 ·
Well...Yes.
I started to re-a


Well...Yes.
I started to re-adjust the TO bearing clearance via the adjustable rod and noticed that the fulcrum arm wasn't initially moving...

Although I replaced the mini spherical bearings in all of the arms, it looks like I overlooked the condition of the clevis pins. Odd in that I don't remember them looking so worn. In addition, when I measured the holes on the ends of the clutch adjustment linkage, one of them is elongated, though doesn't appear so visually. As a result, there's a bit too much play at the point where the adjuster rod attaches to the fulcrum arm. I've ordered a couple of new pins and the ends of the adjuster....

This wear helps explain why the TO bearing clearance seems to change...The parts should be here Monday....More later!

Thanks for asking..
 
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Discussion Starter · #18 ·
Follow up:
After a bit of hea


Follow up:
After a bit of head scratching, the clutch is now properly adjusted...and holds the proper PP to TO bearing clearance of 1.8-2.0 mm.

I adjusted the cable via the pedal stop and cable adjuster at the release arm to allow to TO pivot point to move towards the front of the car, hence creating more (than specified) offset at the referece point (hole on fulcrum arm)...

The WSM specifies a 5-6 mm offset...and I was originally adjusting to that spec coming from a zero offset on the arm. Instead, by lengthening the cable, I started with an excessive offset of 20 mm, and adjusted back to 6 mm....then set the TO bearing clearance. By setting the clutch this way, the spring naturally wants to return to the "normal" offset position, and when the pedal is depressed, the YO bearing does not engage the PP beyond its normal disengagement range.

Although being a multiple degreed engineer, geometery was never my strong suit. Many thanks for all of your helpful input.

Regards,
David
 
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Discussion Starter · #19 ·
Follow-up:

A few miles on t


Follow-up:

A few miles on the car now, and I was having a bit of difficulty engaging RM and 1st. Despite all the adjustments at the clutch housing appearing correct, it seemed as if the clutch wasn't disengaging "enough."

The solution: Adjust the clutch pedal stop upward, hence allowing more clutch throw...After re-adjusting the linkage at the clutch, she now engages all gears, wth ease....hot or cold.

Finally...really, finally done with this adjustment.


Regards,
David
 
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