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nv4500 clutch problem

yeti92

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Location
Tennessee
hey all, i've got a 92' k1500 i just swapped a nv4500 in to so here's the full story and my problem. I started out with a nv3500. transmission was fine other than it wouldn't go into 1st gear sometimes, but anyways the case broke so i put a nv3500 from a 97 k1500 with the internal slave cylinder setup put a new clutch and flywheel replaced all bearings and the clutch master cylinder, bled the system completely started it up wouldn't go into any gear. I got a good deal on a nv4500 that came from a 93' k1500 still had the new clutch in it so all i replaced was the slave cylinder and throw out bearing, bled the system completely get it all together start it up, once again won't go into any gear. i called SACHS and we determined it to be a defective clutch kit. I now buy a hole new clutch kit, flywheel and even clutch fork, once again replaced all bearings (throw out bearing bronze pilot bushing) , torqued, greased everything to spec, got it all back together, start it up and yet AGAIN won't go into any gear i'm so freaking frustrated :mad2:. Any help will be greatly appreciated, i miss my truck and tired of wasting money, thanks in advance.
 
i can see the slave cylinder pushrod pushing the clutch fork through the inspection hole on the side of the bellhousing, it pushes the clutch fork just past the inspection hole i don't know how far it's suppose to push it. other than that i can't actually see the operation of the clutch itself, like i could with the 97' setup.
 
How strong does it pull in gear if you crank up in gear with clutch pushed in? Does it try to pull the truck or will it slip?

Is there a problem with the motor bellhousing dowels or other that the transmission is not sitting square and flush?

I don't know if you can mix and match master and slaves? Its a pain to bleed the hydraulic systems and they kind of finish bleeding themselves over the first couple of days driving and sitting.

Not a mix match of PP for solid vs DMF?

Not sure if you can put the disc in backwards and it catch the flywheel bolts????
 
if you try to put in gear and start it the truck jumps and the gear you're in binds up.

as far as i know there isn't, once i lined the splines and the dowels the transmission went on smooth.

i looked into that and i believe the only differences were the way they mount, but everything is now back to the orignal setup with all the parts being for the year of my truck. Bleeding isn't an issue as i have the phoenix self bleeder makes bleeding a breeze.

i don't understand those acronyms.

naw that's not possible, only goes one way unless you had longer bolts to reach the flywheel then you might successfully put it in backwards.

i'm thinking i'm not getting a long enough stroke at the slave, anyone know how far the pushrod is suppose to extend?
 
Bleed it until your eyes cross and uncross. Takes for-freaking-ever. You sure your trans shift linkage is on correctly and not backwards/upside down? Because sometimes that can cause it to go into 2 gears at the same time.
 
Has the flywheel been surfaced? If it has been ground down to much with a new disc the throwout arm won't be able to push it down enough. Also I have seen some of teh aftermarket clutches where the pressure plate surface will have a step on it that will cause uneven apply of the disc and cause them not to release. When somebody presses teh clutch down, does it instantly move the throwout arm once they start to depress the clutch pedal or does it wait a little? How far would you guess it is moving teh pressure plate fingers down? You should be getting about a 5/8" or so of travel at teh pressure plate fingers to release the clutch. And when you installed teh clutch, at what height did the fingers appear to be at? Were they sticking out, level or going in? Some pressure plates are meant for a stepped flywheel, and when used on a smooth one they will not pull the fingers in far enough which will cause this. Dealing with aftermarket clutches can drive one plum crazy sometimes trying to figure out what is wrong.
 
Btfarm- i'll try to bleed it more but it's tough to push it with your arms so it's as stiff as i would think it could get. How can you put the shifter upside down/ backwards, doesn't it only go in one way?

schiker-none of it's mismatched anymore, it's got the reccomended flywheel and clutch kit for my year/model/engine size so all parts are correct heres the part numbers SACHS K1909-06 91-95 5.7ltr and SACHS NFW1023 flywheel

Thefermanator-the flywheel is brand new, to be honest i didn't check for the fingers being ramped or angled before installation, yes when the pedal is pushed the slave cylinder pushrod pushes the clutch fork instantly, i can't actually see the throw out bearing pushing in the diaphragm fingers with the external slave cylinder setup but the the slave cylinder pushrod is definately pushing past 5/8" (could it be pushing it in too far? i've only tried putting it in gear with the clutch to the floor), like i said i didn't check height or finger design, the clutch guy at SACHS looked into the height and saw no difference between the supposedly defective clutch and the one i just bought. My brother says to shim the clutch fork where it pivots but the guy at SACHS said that'll work but you shouldn't have to do that if the parts are correct.
 
I called the SACHS guy again yesterday, and he told me to add some length to the slave cylinder pushrod to see if the added travel will allow the clutch to disengage.
Well that didn't work, so i also removed the shifter to see if there is anyway that is in wrong, and once again that's not the problem. I'm gonna try to bleed it a bit more when i get day off, but I'm stumped, i tried shifting into gear with the pedal half way out thinking maybe i'm getting to much travel but that's not an issue, i don't believe.
Thanks for all the help so far guys and gals. I'm gonna keep working at it til i figure out the problem, which will hopefully be soon lol
 
How is the pilot bearing to input shaft???? If they are bound up or froze together it wont go into gear either.
 
Okay, so i've bled it for over 2 hours and then some more. so bleeding can't be the issue. The reason the added length didn't work is it STILL isn't getting enough travel.

This time when i pulled the trans i looked at how much travel i'd need the clutch fork to move, to move the throw out bearing to the end of the sleeve, and the slave cylinder pushrod would have to push the clutch fork to the back of the bell housing just to get the TB to end of the sleeve. So i shimmed the hell out of the slave cylinder and i still can't get the travel needed, so there has to be a problem with the way the clutch fork is pivoting on the pivot ball, but theres only one way i can adjust it to get the TB to the end of the sleeve, if i tighten the adjuster down less travel at the slave end and causes less travel for the throw out bearing.

Now my question is either my pivot ball is worn out/bent or the TB doesn't need to travel to the end of the sleeve and if that's the case how far does it need to travel on the input shaft sleeve?
 
A worn ball and fork socket can certainly be an issue with not enough travel.

Does the tranny shifts smootly in all gears with engine off and clutch engaged and/or disengaged?

What do you mean by "gear it's in binds up",...does the engine stall?

To make sure it is the clutch giving trouble and not the tranny or T-case
Can you start and drive away with the shifter in first gear?
 
I have seen many clutch fork pivot ball studs worn out causing major clutch release headaches on NV4500's. It causes high pressure in the hydrolic system that the master cylinder to crack and spray fluid out. Hope you got your issue figured out, these can be no fun.
 
Well i pulled it and put it back in for the fourth time and yeah the pivot ball was worn to hell so this time when i put it back in i replaced the pivot ball and also put a second new clutch fork in it as the other new one was damaged from the worn pivot ball.
While i was at it i put a pre-bled pre-assembled master cylinder and slave cylinder assembly in it just to be 100% sure that wasn't an issue as far as the bleeding goes even though i was 99% sure i had it all bled.
I've been through two brand new clutch kits replacing the bearings every time, the last kit i used i used a pilot bushing instead of a pilot bearing.
After all this the same problem still persists, i torqued all the clutch to flywheel bolts to spec only doing a few turns in a star pattern at a time so i know the clutch is installed correctly.
What i mean by "gear it's in binds up" is when i crank the truck in granny low, the truck rolls but it's got 42's so it doesn't actually start and the reason it binds up i believe is because i don't have an e-brake and the truck is on a slight incline so the truck's weight is all on that gear, it takes two hands to pull it out of gear.
Oh and yes when i started it i had my foot on the clutch pedal all the way to the floor, since right now even i'm starting to think i must be the biggest idiot ever for it to still not be working.
I just don't understand how this is happening, i've never heard of anyone having this problem like me, especially after replacing every part of the clutch and clutch hydraulic system.
 
Sometimes when the pivot ball is worn out it changes the angle of travel on the throw out bearing. The throw out bearing will rub against the transmission input shaft bearing retainer (I call it a nose cone) The throw out bearing rubs so hard that the clutch pedal gets stiff, usually other problems asrise like the master cylinder leaks or the clutch lines breaks. In fact you can see the convex wear angle on the input shaft bearing retainer. IMO as long as the clutch pedal goes smoothly to the floor with out a ton of effort you have the clutch installed correctly, and its bled properly. However I has seen weird clutch problems caused by the crankshaft thrust bearing. Pry back and forth against the flywheel. It shouldnt move more then a few thicknesses of a piece of paper.
 
Well i'm hoping that's not the issue as the clutch pedal goes down smoothly and definitely doesn't feel like it takes an abnormal amount of effort and the bearing retainer looked to be in good shape as i had another person inspect it also last time it was out. The only thing i can really think of right now is maybe the pivot ball adjuster/bushing isn't adjusted right as i've adjusted it the same way every time i've installed the trans. This video at 11:56 http://www.youtube.com/watch?v=SSX9gv0yAPs the clutch fork is sitting half way in the inspection hole without the clutch pedal depressed, mine is sitting before the inspection hole all you can see is the back of the clutch fork and when the clutch pedal is depressed it only travels to where the guy's clutch fork is in the video at 11:56. Bare in mind that this is a nv3500 and it's a used clutch in the video but still i think that may be my issue, but if i tighten the adjuster down the throwout bearing won't go all the way to the end of the bearing retainer sleeve, does it not need to? Anyone got any pictures of a correctly adjusted clutch fork? Thanks for all the help guys it is very well appreciated.
 
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