You might be able to do an access panel to the fuel pump under or behind the passenger seat, once you figure out where exactly the body is going to be.

on to the clutch... Does this input bearing retainer-collar seem too short? When the throwout bearing is pushed all the way forward it seems like it will only be halfway on.

It'll probably work, can you estimate the length of throw, and where the sliding collar starts, relative to the end of the input retainer snout?

You could run a longer body to the throwout bearing holder. The input retainer snout you pulled -- is it the same OD? How do the retainers that you have vary, exactly (clearly length, but what else)?

If it proves to be a problem, you could have a shop surface the front and rear of the bellhousing on a mill -- simple setup, so it should be pretty reasonable, price-wise. Lots of options are available -- part of the joy of rolling your own! <img src="/forums/images/graemlins/pfft.gif" alt="" />

Randii

Randii, OK I need to find the throwout bearing throw length before I can figure this out so I should probbaly back up a second.

Lets start with the pilot bushing. Here is what my crank looks like now. I am ASSUMING the old pilot bushing is still in there.


I can gouge it pretty easily with a little hammer tap and punch so I am assuming that is not the crank.

It is however very stuck and there is no internal overlap to use a puller or do the grease trick. Not sure how I can get that thing out of there.

Assuming this is the pilot, I calculated i will need a pilot that is .43"ID x 1.25"OD x 2" long

Next would be pressure plate ratio. According to those articles on Novak's site, since my pressure plate is ~9.5" they suggest my pressure plate ratio as approximately 4.5 to 1.

I looked at my pressure plate and noticed the fulcrum is a thin rod bent in a circle that is held in between those pins and the stamped section after it. It also seems like the end of the "fingers" are right at the outside of the circle near the springs.

I measured the long arm at 2.75" and the short arm at about 1" so wouldn't that make my ratio 2.75 to 1?????? Why would the Novak site suggest 4.5 to 1?



The Novak site says the pressure plate must move .10" to .12" in order to provide an air gap of .030" to .050". So If I take .12" and times the pressure plate ratio (2.75:1) I get .33". They suggest I add in a freeplay amount of .06" (1/16") to bring the total amnount the release bearing moves to .39"

My clutch fork is even on both sides. It is a 2:1 ratio since the release bearing is right in the middle. So the slave rod will need to go .78" in order to move the release bearing .39"

Seem somewhat accurate???


My slave cylinder is .75" bore and master is .625 (5/8") bore. This would meen I have a hydraulic ratio of 0.833

To get the slave to move .78" I would have to move the master .93 or about 1" which is about half the stroke so I should be OK there.

The stock zu slave cylinder is .875" (7/8") so it is definetly true what you were saying that the slave is often different than the master.


Last thing is the distance from slave mounting surface to the clutch fork and I measured 3.75" This worries me a bit and I think I might have to weld in an extension to the shift fork or put a spacer between the shift "block" and clutch fork. I don't think it would be a good idea to put that much leverage on the cylinder.


My slave brasss fitting stripped so I need to get another one and test what I guessed above but here are a few pics from messing around. I think the .75" bore air slave cyl I have might work out fine.

Can't see. Hit what you think is the bushing lightly with a file on the outside lip, away from where the input shaft inserts. The file should skate lightly on the steel of the crank and dig in easily on the bushing. Try both, avoiding seal or mating surfaces.

A good way to check would be to go to the parts store and check the books -- there is a crossreference by dimension, and you should be able to look up the application and back out the actual dimensions to verify against what you measure.

If you are confident that it is a bushing, you should be able to tap threads easily into the bushing and yank it. Odd that the bushing is driven so far in that it bottoms... makes it tough to use a proper puller.

I follow your measurements -- just be sure to remember that the Novak site has general rules of thumb, and they don't always work so well on non-Jeeps. I made sure I'd have extra throw for adjustment, and based my calculations on ACTUAL measurements. About 3/4" at your throwout bearing seems about right, IIRC the Isuzu slave swung about 1.25", which should allow a good cushion for adjustment, and with the pedal swing, a good range of actual foot travel.

Can you build a bracket that reaches inside the bell to hold the clutch slave, but fastens to the outside of the bell? Either that or use an extension rod between the clutch slave and the clutch fork? Does the clutch fork swing across the plane perpendicular with the tranny mainshaft centerline (effective leverage)?

Randii

Randii when I get to the slave cylinder mounting bracket I have a good idea about using a piece of pipe to mount the cylinder halfway into the bellhousing while still being able to remove it from the outside. This might prevent having to use a long rod.

Also found out there is no pilot bushing in my crank. That is the crank.

My new problem is input shaft/clutch spline engagement.






I'm guessing the splines end about 1cm before the flywheel surface and the clutch is only about halfway engaged as it is now.

I'm assuming you would need the clutch disc to be 100% engaged on the input shaft splines at all times?

Use a spacer to push the flywheel closer to the trans? Custom (thicker) flywheel? Mill both sides of bell? What do you think?

Chris

Chris, what application is your flywheel? What vehical did it come out of?

Greg

Car part matched it up to 1996-2002 f-body (camaro/firebird)

Sounds interesting... you definitely want to be able to trouble-shoot and adjust from the outside.
FWIW, I don't see a downside to a long rod, as long as it is stiff enough. I've used threaded rod and coupling nuts to enhance adjustability, which adds value.


I'm not sure if I see what you're saying or showing. The friction disk splines need to be fully (or very close to it) engaged on the input shaft spline. Beyond that, as long as you have:
1.) full engagement of the clutch and flywheel plus a bit of airspace between the throwout bearing and the pressure plate fingers, and
2.) full disengagement of the clutch from the flywheel, plus a bit of airspace between them

Any of your suggestions should help fine-tune this. I think shaving the bell is path of least resistance, as mucking with the crank or flywheel needs done delicately to maintain balance. There are also vendors out there that could also build a friction disk with custom offset (sometimes just a 180* flip), but finding a machine shop to shave your bell (careful with that vowel!) will be easier, assuming you have thick enough flanges and faces on the bell... how thick are they?

If you use any of the above methods to change the alignment of the flywheel relative to the front face of the bell, you'll need to compensate with a simple spacer for the starter. That should be easy, though, since it won't need to be balanced, and can be flat stock with basic grinder work (unless you have access to plasma, waterjet, laser, etc.).

Randii

This is just a drawing of course and not to scale but if the clutch disc was put on right now it would not be totally engaged with the input shaft. I will go the bellhousing milling route.

Thanks for the help