Travel of Clutch Pedal - SOLVED!

[BrownLoaf]

After searching for an answer, I've found related discussions but not a specific answer.

What is the correct clutch pedal travel? In other words, how close to the floor should the pedal be when it stops traveling?

On one van (83.5) the pedal stops about 2 inches above the floor and another van (87) travels completely to the floor.

I understand it may be possible to adjust the length of the pushrod above the clutch master by adjusting the clevis and locknut. Could this adjustment be the cause of the difference between the two vans? Specifically, could the pushrod on the 83.5 be set "too long" causing the piston in the clutch master to bottom-out in the cylinder before the pedal travels completely to the floor?

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83.5 Vanagon Riviera WBX 2.2 "Brown Loaf"
87 Vanagon Syncro Tin Top WBX 2.1 "Bubbles"

[4Gears4Tires]

I hope you get a good answer.

My 87 travels all the way to floor. I would love to reduce the pedal travel to 60-75% of it's current range.
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'87 Syncro
Ferric Oxyhydroxide Superleggera Edition

[dobryan]

I have had 5 Vanagons. They all travel to the floor. The clutch catch point is of course not at the floor.
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

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[Sodo]

I’ve never heard of clutch pedals not reaching the floor.
That’s a new one on me.
I do know the engagement point rises towards the top as the clutch wears wear out and then engage too close to the floor
ooops the engagement point rises as the clutch wears.

Grab ahold of the pedal with your hand and pull up/down, does it have slop at the top?
Measure the amount of slop.

It seems that many vans were assembled at the factory with the clevis “dry” and 30 years later, the clevis wears out (on those 'dry' vans)
My '90 clevis pivot still had grease on it and was in perfect-as-new condition.

By the geometry, the slop in the clevis is 1/6 of the slop at the top.
At 1 inch of top-slop the clevis pivot is getting pretty close to failure.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[BrownLoaf]

Thank you for the replies so far.

The pedal has about 1/4 inch of slop at the top. The clevis begins moving down almost immediately as the pedal is depressed.

_________________
83.5 Vanagon Riviera WBX 2.2 "Brown Loaf"
87 Vanagon Syncro Tin Top WBX 2.1 "Bubbles"

[Sodo]

You wrote 83.5 and 87 vans.
Are the clutches all basic VW, or is there a conversion/diesel/other details?

Logan....your ^^pic with the mirror^^ is a great pic for TheSamba

Good stuff. I didn't know it was visible in any way.
I suppose it becomes visible while the pedal is pressed, thus you cannot observe the 'slop at the top' right?
At least your pivot looks like it has grease on it.
What year is this van?

Anyone with an old van should look and see if that pivot appears dry/dusty.
And if it is, try to squirt it with an oil.
Or pack some grease into the pivot.
WD40 will evaporate in a few weeks, use a "real oil".

Would a mechanically minded kid (with a tiny hand) be able to pack grease into that clevis?

Clutch clevis pin failure is a big, expensive, difficult problem for these old vans. It's kinda easy for someone who's done it a few times.
Or for a vanagon specialist/shop.
But very difficult for a first-timer.
A garden-variety mechanic shop would be wise to NOT bid the job because it could take all day.
And repair requires welding.

Here is a pic of a clutch clevis and pivot pin that has been dry for many years, perhaps since MFR (new). (photo belongs to JFLACROIX)
I would imagine..... that on this van, the clutch could hit the floor without disengaging all the way.
The up/down at the pedal would be 6x the slot plus the diameter reduction of the pin.
By eyeball it looks like 7mm +1.5mm +1.5mm = 10mm slop at the clevis.
The pedal is 6:1 so at the pedal the slop is 6x 10mm===> 60mm. (minimum)
Perhaps 2.5 inches up/down at the pedal.
Which would limits the disengagement the same as a 2.5 inch block of wood placed on the floor.

As the clutch disc wears thinner, the engagement point rises, right?
Perhaps mitigating the loss due t the slop.
But this van (in the pic) with a NEW clutch installed..... is it possible that the clutch would hit the floor before disengagement?
Perhaps causing accelerated wear on the synchronizers and difficult shifting.(?)

OK that's slightly off-topic but perhaps useful 'clutch diagnostic theory'.
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[Mateo83]

My early 83 goes to the floor.

[hardway]

The newer Smallcar Subaru conversions limit the clutch pedal travel to prevent the slave cylinder from over extending. To my knowledge on all stock Vanagons the floor is the stop for the pedal.

[4Gears4Tires]

[Sodo]

oops, edited

[BrownLoaf]

All the feedback is much appreciated.

This is on an 83.5 WBX vanagon with stock clutch and transmission. The clutch has roughly 3000 miles on it (less than a year old).

With the mirror, it actually is possible to watch the slop at the top of the pedal stroke. There is no slop (clevis moves immediately) as the pedal is moved down. There is about 1/4 inch of upward slop at the pedal pad as the pedal is lifted up from it's top resting position. Given this, I believe the clevis/pin joint is still in good condition.

I did use a q-tip to try to shove some moly grease up into the pivot this morning.

To test my theory of the pushrod being adjusted "too long," I first checked that the ball of the pushrod is bottoming completely into the socket on top of the piston. The pushrod inserts surprisingly far into the master cyclinder and I wanted to be sure the pushrod was not getting hung up before bottoming out into the socket.

Next, I removed the pushrod, cleaned it up on the workbench, adjusted the nut to "shorten" the pushrod, reinstalled it, then checked the clutch pedal travel.

The pedal now bottoms-out closer to the floor, but not completely on the floor, as it should. Additionally, at the top of the stroke, there is clearance between the pushrod and the piston greater than the .5 mm maximum specified in the Bentley.

So it seems my theory is false and the issue is elsewhere. The only other cause I can think of right now is that the master cylinder has an internal issue preventing the piston from traveling completely. However, I am failing to think of what would make the piston hit such a hard stop. This master cylinder was installed in September 2019 and is part number 251721401AMY.
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83.5 Vanagon Riviera WBX 2.2 "Brown Loaf"
87 Vanagon Syncro Tin Top WBX 2.1 "Bubbles"

[BrownLoaf]

[Sodo]

You wrote it's a hard stop, that feels like it's bottoming in the master cylinder.
This is strange.
Possible the master cylinder is defective or some "wrong part".

Maybe watch the slave, and have someone press the clutch hard at the bottom and confirm the slave has proper extension and not topping out?
I have never heard of this, just offering ideas.

Some member knows the measured displacement of slave travel output that you could measure and confirm.

Could there be some problem with the clutch fork in the bellhousing?
I'm not real familiar with that component anymore, I have a Smallcar setup.
Which required some re-engineering and diagnostics too!

Logan I think your diagnostic methods and conclusions as you march through this problem are good.

My van has 1/4" of pedal slop and the clevis and pin were greased, and 'as new'.
Greased/not dry runs 200k miles with no wear at all.
I don't think there is any benefit to beef up this pivot or clevis, simply "don't run it dry".
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'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb

[vanis13]

[BrownLoaf]

[hardway]

The part # with the AMY as a suffix probably came from IMC. The MY on the suffix indicates the brand is Meyle. That brand has a mixed track record. Some of their suspension components are excellent. Their plastic cooling system stuff has always been problematic to junk. Some of their products they either manufacture or contract out the manufacture to their specification, like the suspension stuff. I suspect that some of their products now are just re-boxed.

Selecting appropriate parts and refusing inappropriate parts is an important skill. IMC has no stock now of any brand of 251 721 401A. WorldPac has two brands available now, both Chinese. Van Cafe/ RMW has an FTE in stock. I would not use anything other than FTE or ATE in a Vanagon.

Why don't you unbolt and shift the clutch master cylinder. Then you can push the pedal without the cylinder in place. You can then prove whether the "stop" is in the pedal assembly or the cylinder.

[BrownLoaf]

Thanks Hardway.

Not to jump ahead and conclude the master cylinder is the problem, I will say it was purchased from a well known Vanagon parts supplier. I too have had issues with Meyle parts, as well as new OEM parts that are now made in different factories and some that even performed worse than the nearly 40 year old original part they replaced. It's a tough battle finding the good stuff these days!

I may be ordering one of those FTE masters from VanCafe today. Thanks for letting me know they are in stock.

With the pushrod removed from the clutch pedal (taking the clutch master out of the equation), the pedal travels completely to the floor.
_________________
83.5 Vanagon Riviera WBX 2.2 "Brown Loaf"
87 Vanagon Syncro Tin Top WBX 2.1 "Bubbles"

[hardway]

Now that you have proven that the pedal itself moves normally you now know that the problem is downstream form there. The problem could be in the bellhousing. The hydraulic linkage is not supposed to hit a hard stop. The release bearing and pressure plate spring should have travel to spare. If something stops the motion of the slave cylinder and thereby the master cylinder also then that would explain the observed phenomena. The hydraulic linkage can produce a lot of force. Like a brake hydraulic system. You could loosen the slave retaining bolts and see if greater travel is achieved. Of course if you loosen it too much then the piston in the slave could over extend.

After everything else has been ruled out, whatever remains must be true.
(Attributed to Arthur Conan Doyle.)

Good hunting.

[BrownLoaf]

Thank you! I'm getting somewhere, even if it's not what I hoped.

To isolate the clutch hydraulics from the release bearing and pressure plate, I pushed the slave pushrod and piston to bottom-out in the cylinder (second photo), wife pressed the clutch pedal while I held the piston up preventing refill of fluid, and she observed the clutch pedal now going to the floor while pushing the pedal down against me.

So it seems the problem is not with the clutch hydraulics and is actually within the bellhousing, related to release shaft, throwout bearing, and pressure plate.
_________________
83.5 Vanagon Riviera WBX 2.2 "Brown Loaf"
87 Vanagon Syncro Tin Top WBX 2.1 "Bubbles"

[BrownLoaf]