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nv4500 clutch problem

all you need to worry about is that the throwout bearing is not in constant contact. ie the clutch fork shoul have a lil play before the throw out bearing is engaged
 
Olddieselguy could that much damage happen from just depressing the clutch pedal a few times? How would you go about prying the flywheel back and forth as that seems like a very good possibility as the engine is ticking loud and i tried adjusting the valve backlash and determined the camshaft to be worn out which means the metal shavings from the lobes probably got to the main, rod and thrust bearings. I spoke to one of the clutch experts at perfection clutches and he said that since my motor is worn out that all parts wear together and the new part would have to wear or it would just not work with the motor being worn out, and he agreed with your flywheel idea.
 
I think you've covered all the main things that would tend to make the clutch stick. But if its not pulling hard enough to roll but that tight can you smell clutch disc after a while like its slipping or any heat build up from extended rubbing????

Could it be the input bearing on the transmission that is causing it to bind in gears? Do all gears bind or just 1st/2nd? Have you ever tried 3rd, 4th, 5th, and reverse? Do they all do it too (not want to shift out of gear)? I don't know how its arranged but the previous owner of my truck told me he was driving in a parking lot and pushed the clutch in and it did not disengage from engine. Under warranty they replaced the transmission input bearing and I guess the input bearing snout cover thingy???? Along with the clutch/PP.


How about no load on the transmission. Put transfer case in neutral will it shift thru the gears ok then???? When the truck is off I take it it shifts ok? Leave transmission in gear can someone turn the driveshaft with engine off clutch pushed in would have to jack rear tires off ground?
 
I take it the pedal feels a bit better now and feels like it ought to work but just won't shift correctly ???? How does the clutch pedal feel. Is it like its pushing smooth and travelling well and just won't disengage?
 
I am guessing that is a good way to test input bearing idea. engine off jack wheels off ground push in clutch to floor and see if you can turn the drive train via wheels or driveshaft. To see if its some out of round or worn issue that while running that binds up the input shaft and clutch etc????
 
It's pulling hard enough to roll but the truck has 42" inch tires on it and I have a platform built under it just to get the transmission up into the truck because my transmission jack would be well maxed out before it got to the height needed just to reach the transmission. Like I said the reason I believe it feels like it binds up is because it's holding the hole weight of the truck after rolling forward and then backwards if I probably grabbed the brake before it rolled back it'd probably come right out of gear but I haven't tested that theory nor am I really trying to get the truck started and take off as once it rolls that tells me right there that the clutch isn't disengaging right? Would that be the on 97' k2500 that is in your signature? Because if that we're the case that sounds like it would of effected the concentric slave cylinder I don't know if mine could have that problem since I've got the external slave cylinder. With no load engine running all gears shift fine, engine off something all gears shift fine. Clutch pedal feels great and smooth, I'm getting excellent travel now with the pre-bled pre-assembled hydraulics in it. But yeah I could jack the rear up and try your idea anything is worth a try at this point for sure.
 
You should have no problem putting the stick in neutral with the clutch depressed truck rolling or not,engine off or running.
How is the splines look on the input shaft,if they're worn in a bit)creating an offset part in the splines) it might prevent the disc to slide backwith the clutch disengaged
Also, is the disc installed correctly with the spring pack facing the tranny(i think,..its been a while)
 
Input shaft and bearing bound on my NV4500 I recently rebuilt because I screwed up on the preload/reassembly. OnceI had the shims in right problem solved.
 
Bison, yes it should but the clutch isn't disengaging so it's like putting your truck in gear and starting it without the clutch pedal depressed. Last time I had the clutch out I moved the clutch disc back and forth on the splines and it went smooth and didn't twist. as the splines can get twisted from wear. the splines looked good. theres no way to put the clutch disc in backwards as it says right on it FLYWHEEL SIDE. Tanman_2006 what happened when the input shaft and bearing bound was there any noise etc? How did you diagnose that to be the problem?
 
I never drove it but I could start mine out of gear. It was hard to get in and out of gear and the engine would die when I let out of the clutch. It was binding up.

Sent from: Source Unknown
 
Today i took a steering wheel/harmonic balancer puller and bolted it to the side of my bell housing and ran the rod all the way down pushing the clutch fork (with the truck in gear). Low and behold the clutch released and i could spin the output shaft on the transmission. I then used the same puller to push the piston in on the slave cylinder to verify that i had no air in the system and i don't.

I hooked the slave cylinder back up, and still not traveling where i need it to. I don't understand why it's not getting the travel needed, i know the slave cylinder can travel that far but it's like it's not getting enough pressure. Could there be something wrong with the clutch itself requiring more hydraulic pressure than the factory system pushes out?
 
Are you sure the pedal is returning all the way out??
Or the rod is in all the way on the master cylinder?
 
Sounds like the master cylinder has an issue with not matching the volume/stroke that the slave needs.
Might be the master cyl piston ain't bottoming out on the backstroke or the valve/cup is leaking some fluid back to the tank on the forward stroke,resulting in less fluid avalable to reach the full stroke on the slave.
 
Are you sure the pedal is returning all the way out??
Or the rod is in all the way on the master cylinder?
yes
and yes.

so how do i determine these two problems?
 
Have another person push the pedal slowly in while you look in the fluid tank for fluid bubbles which indicates fluid is bypassing the plunger cup.
 
I had a clutch on a 95 that would not disengage similar to yours,but on mine the pivot ball and fork socket was worn.
I ended up making a 3/4" longer pushrod from a long 5/16" bolt between the slave and the fork.
Worked fine after that,..well anyway it did till i totalled the truck 10 days later :WTF:
 
I read through your entire thread and I don't see any mention of the throw out bearing being installed incorrectly. The older nv4500 throw out bearing has a clip that is counterintuitive and if you put it on fork wrong you will need way too much travel. I don't have pictures here but I thought it was worth mentioning.

I am fighting my new install as well, new master, slave, but extension on slave, new fork (worn pivot ball though) new Sachs clutch kit, new flywheel, and I don't have quite enough clutch works good when cool but grinds gears when hot.
 
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