Clutch fork throw

[EuroDat]

Yes, try the new fork. If thet doen't help much then it must be the flywheel or something with the thrust bearing in the crank that holds the crank shaft in place.

One other measurement you can take is the distance from the bell housing to the throwout bearing. Set the fork up at the 115mm mark and use a straight edge other the bell housing next to the input shaft. With your collar, the measurement you should read is 66 to 67mm from straight edge to throwout bearing. If you get that, then the problem is not in the pivot ball or fork.

Normally the fork to bell housing distance should be in the 112 to 118 area. 124mm might be ok, but I think I would be putting two 2mm thick washers behind the spring washer on the pivot ball. That 4mm will get you about 7mm on the fork end and get you in the zone.

Edited July 12, 2020 by EuroDat
Typo

[Zed Head]

6 minutes ago, EuroDat said:

 then it must be the flywheel or something with the thrust bearing in the crank that holds the crank shaft in place.

That's a good one.  That should show up at the front of the crankshaft.  The damper pulley should be projecting forward.  You'd see it in your belts and pulleys, they'd be misaligned, from damper pulley to water pump, etc.  Might also see it in the distance from the flywheel edge to the back of the block.  That's a more direct measurement but someone will need to verify theirs for you.

Never heard of it happening but all of your other numbers seem right.  Seems like a crankshaft misalignment would cause other problems too though.

[Zed Head]

The distance from the friction surface of the flywheel to the back of the engine would tell you something about if the flywheel is thin.   Again, somebody will need to get you a proper measurement to compare to.

[rcv]

Ok transmission is back on with the new style fork.  It looks like I’m down to a little over 125mm now:

Here’s a video of me fiddling with it: 

26 minutes ago, EuroDat said:

124mm might be ok, but I think I would be putting two 2mm thick washers behind the spring washer on the pivot ball.

I’ll take your advice and try this out.

16 minutes ago, Zed Head said:

You'd see it in your belts and pulleys, they'd be misaligned, from damper pulley to water pump, etc.

I haven’t installed my belts yet, I was going to wait until the engine was in the car, but I’ll do a test fit now to see if anything weird shows up. 

[Zed Head]

It still looks wrong.  Is it possible that the clutch is already disengaged?  Put the transmission in gear and see if you can turn the output shaft. 

Maybe when you install the transmission you're pushing the throwout bearing in to the pressure plate, disengaging the clutch.  That could happen if the nose of the front cover is binding inside the throwout sleeve.

Also, and this is minor, but there should be a spring on the back of the fork that holds it on to the pivot ball.  It shouldn't be loose like you show in your video.  Just another odd thing.

[Zed Head]

Or, maybe because the holding spring is not in place the fork is slipping off of the throwout sleeve.  So maybe that's actually a major thing.

That spring on the back of the fork should be set in place, clipped over the pivot ball, at the same time you clip the throwout sleeve under the fork tine springs.  All of the those parts are firmly held in place and aligned by the spring clips and the nose of the front cover.

I see the edge of the spring in your other pictures but it doesn't seemed to clipped on to the pivot ball.

Example from internet - 

Edited July 12, 2020 by Zed Head

[rcv]

19 minutes ago, Zed Head said:

there should be a spring on the back of the fork that holds it on to the pivot ball

The retaining spring on the back of the fork is there, and I made extra sure it clipped around the groove in the pivot:

 

19 minutes ago, Zed Head said:

Is it possible that the clutch is already disengaged?

Nope, I put a little piece of tape on the output shaft and watched it spin as I turned the crank with a ratchet. 

52 minutes ago, Zed Head said:

You'd see it in your belts and pulleys, they'd be misaligned, from damper pulley to water pump, etc.

 

The belt I bought seems to be a little short so I can’t get it on, but the pulleys seem to be well aligned according to my ruler. 

[Zed Head]

11 minutes ago, rcv said:

The retaining spring on the back of the fork is there, and I made extra sure it clipped around the groove in the pivot:

Nope, I put a little piece of tape on the output shaft and watched it spin as I turned the crank with a ratchet. 

Weird that you can pull it so far forward if it's clipped on.  When I messed with mine I was always worried that I'd accidentally pull it out and not be able to get it reclipped.  In your video you're moving the fork completely off of the pivot ball.  It's normal to be able to move the sleeve back and forth but the fork should stay on the pivot ball.

The shaft turning could be light drag.  I'd make sure that it's firmly engaged.  Put a rag on the output shaft and use some pliers to turn it, against the force of the engine.

It just looks like your fork is way too close to get full disengagement.  You could even measure that distance between fork and case until the fork bottoms out on the case and see if it is more or less than the slave cylinder stroke.  Just looks like you're going to bottom out on the case.

Anyway, thanks for the puzzle...

 

Edited July 12, 2020 by Zed Head
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[Zed Head]

Here's my last one, until I think of another one.  I think that it's been mentioned but it's worth reconsidering.  Your pressure plate is being held open.

Maybe your clutch disc is too thick.  This would hold the pressure plate open and move the pressure plate fingers down.

Or, and I don't really know if this could have the same effect.  The disc is on backwards.  If the disc is on backwards it can be pressed on to the flywheel bolts.  This might be enough force to make it hold the pressure plate open.  It would also engage the transmission with the engine, making it seem like the clutch is engaged, but never allowing you to disengage.

Since all of your other work seems right, that seems most likely at this point, to me.  Your pressure plate is being held open by something, causing the fingers to be depressed, causing the fork to be out of proper position.

[rcv]

29 minutes ago, Zed Head said:

Put a rag on the output shaft and use some pliers to turn it.

I put the driveshaft on, and with the transmission in gear I was able to spin the front pulley. I then had a helper turn a ratchet on the crank bolt while I held on to the driveshaft and I can confidently report that the two are very tightly coupled. 
 

29 minutes ago, Zed Head said:

You could even measure that distance between fork and case until the fork bottoms out on the case and see if it is more or less than the slave cylinder stroke.

Good idea - it looks like I only have around 12mm of clearance between the back of the fork and the case when the TO is touching the springs. Half of the slave stroke can’t be good ?
 

15 minutes ago, Zed Head said:

The disc is on backwards.

I was pretty careful with this, so I’m fairly confident it’s on right. I installed it in the only way that makes sense to me, which is consistent with Tom Monroe’s instructions:

 

I would absolutely consider just buying another clutch kit if I thought it would help, but given my 91mm stack up I don’t think it will. 

I don’t love having to resort to the washers under the pivot, but I think that’s my best shot at this point. 
 

EDIT

I just reread your comment about the clutch disk being too thick, which could be pulling the springs inwards. That geometry makes sense, But given that the pressure plate and disk are sold as a kit, it would be pretty weird for this to be the case right?  My 91mm stack up number doesn’t have anything to do with the clutch disk, so maybe there is something wrong there. 

Edited July 12, 2020 by rcv

[EuroDat]

Yes. That 12mm travel is not enough. You need about 15 - 20mm normally depending how fine the clutch pedel is adjusted. 12mm the clutch pedel most probably will not reach the floor before the fork bottoms out.

I was thinking about a thicker than normal clutch disc, but I have never seen that happen. Always a first though.

 

[EuroDat]

While we are on the subject. The figure CL-16 shows the stroke at 35mm. That is the maximum stroke of the slave cylinder, not the operating stroke which should be max 25mm with all adjustments done correctly.