Clutch fork throw

[Dave WM]

I just installed the Excedy 240mm (6030) kit. I reused the collar that was in there with the autozone 225mm (looks like the pressure plate in the above pic). The pressure plate was quite a bit thicker than the one that came out. It all worked out fine, I will get some measurements on another collar that I have, that was very close to the one that I ended up using. It looks taller than the one in the pic above. The Excedy seem to be a touch lighter in feal, and much smoother than what came out. I used to get a tiny bit of chatter if I did not feather the clutch just right when starting off from a dead stop at low rpm's. The 240mm Excedy has no hint of this. I also check the pilot bush with the alignment tool, the old one had a lot of play, so I pulled and installed the new bush. It was so tight on the tool that I could not extract the tool with the pull ring, I had to use pliers to pull it out. Took two tries (removed and reset the pressure plate with the alignment tool pressed in more fully) to seat the bell housing. 

I used guide two pins, trans in gear so I can turn the output shaft, a trans jack, and still it was a bear.... I did check the input shaft thickness with a micrometer to the alignment tool just to make sure it would fit, it was a hair thinner so I know it would fit the bush.

While in there I replaced the rear main seal, as it was leaking there. 

[texasz]

On 4/22/2021 at 9:59 PM, rcv said:

Nice, those mostly line up with the measurements in my image (repasted below for reference).  The only one I can't really match up is the bottom-right in your image with the 46.84mm ear to TO measurement.  Do you happen to know what vehicles each of these originally came out of? It would be helpful to label them if so.  Also, one more measurement you could take would be from the top of the throwout bearing to the top of the collar.  I'm pretty sure this is a functionally useless measurement, but it's what's provided in all of the other collar images I've seen (e.g. https://www.classiczcars.com/forums/topic/64212-clutch-fork-throw/?do=findComment&comment=602080&_rid=33357) and would help match your measurements to other images.  Thanks for doing the legwork here, I'm sure it will save someone a lot of headache down the road.

 

 

The year and models listed to the left of each picture...would this align to the transmission being used I presume?  For example if you have an L24 engine with 5-speed from a '77 280Z you will want the collar that is listed above for the '77 280Z correct?

 

[Zed Head]

Not really sure what's happening here.  Looks like three random posts tacked on to the end of an old thread.  Apparently Patcon has some new parts that don't match the old parts?

[Patcon]

Zed,

Im not sure I have the old parts. That's one problem.

I thought I should verify the stack up height before we finished assemblyof the engine. Which is pretty far off.

I believe the transmission is a 79 280zx 5 speed. I think we reused the collar that was in it, but not positive.  Cody might remember.

Im not sure how well it shifted before we rebuilt it. I know reverse was an issue but the idler gear was rough.

So maybe it wasn't fully disengaging?

I ordered the exedy to compare to the Luk. But even so, I don't know where I would expect to find 18mm?

[Zed Head]

I see.  You're only showing the TOB and bearing.  You have to add the height of the clutch pressure plate, from the fingers.  Set the TOB and bearing on top of the pressure plate and measure down to the surface it's sitting on.  You're only showing half of the stack.

Edit - maybe that second measuremnet is from the fingers?  It's in the ball park of your first picture couldn't tell if you were just showing the smae measurement.

But, your bearing is on backwards.  I see 1.70" and 1.75  from your measurements.   43 + about 44.5 = 87.5 mm.  You might get there with the right bearing orientation, sitting on the finger tips.

Edited August 8, 2023 by Zed Head

[Patcon]

I will reverse the bearing. It's bad anyway and noisey. I wondered if it was oriented correctly.

I will make some better pictures

[Yarb]

Careful before you head down that rabbit hole. Looking at the bearing there really is just one way that guy gets pressed on. IMHO

[Zed Head]

It's a bearing.  It can be pressed on two ways.  How does it become a rabbit hole?

Actually, I can't say for sure that Patcon's is backward just based on the pictures.  But, it's 50-50.  Either way the measurement should be taken with the stack stacked.

 

 

[Zed Head]

On 8/6/2023 at 2:09 PM, Patcon said:

So I have a new issue with Cody's car

My clutch stack up is only 74mm with the current collar to the ears

This picture has the caliper jaws sitting on the top of the sleeve, not the ears.  That might be a short sleeve/collar.  Might be a 240mm clutch part.  The ears are where the spring wire is sitting.  So, that could be the missing distance. 

[Patcon]

So I went to Cody's today and got some more pictures:

I'm going to do all the math here at the top to keep it all together

Fingers to the surface - 1.744" (44.3mm)

Complete stack OA with old bearing - 3.305" (83.95mm)

complete OA less ear offset - 0.415" (10.54mm)

New bearing is 1.692" thick versus (42.98mm)

The old bearing was 1.701" thick but probably lost a ten due to the bearing being backwards

So that looks like 44.3 mm + 42.98 mm - 10.54 mm = 76.74 mm to the ears

[Zed Head]

It's kind of funny how many different ways a person can take a measurement on that sleeve and bearing.

Using my eyeball calibrated to my computer monitor, and referring back to Post #140, I have to surmise that you have the shortest possible throwout bearing sleeve/collar.

Something still seems odd though.  That looks like a tall pressure plate.  If you look at my picture in #149 you'll see that no math is necessary.  That's a straight piece of wood sitting on an ear (hard to see because the camera is head-on to the ear) and extending out to where I could get a clear measurement to the surface the pressure plate is sitting on.  With a cheap caliper that reads in metric, so no math.  Direct metric measurement from ear surface to plate surface.

Anyway, not sure what's going on there.  Looks like you'd gain about 10 mm with the longest sleeve/collar.  But your math says that still leaves you short.

[Zed Head]

For what it's worth, Perfection shows a tall collar.  Of course, the pictures often don't represent the actual parts.  But, it's for the same car, a 79 280ZX.  The 06009 is a choice there too.

p.s. I had a Perfection for a while but really didn't like it.  Stiff pedal and it chattered really bad when it got hot.

https://www.rockauto.com/en/moreinfo.php?pk=334529&cc=1209293&pt=1993&jsn=393