NV4500 Installed

[R.E. Miller]

Finally got my truck back together today. After much strife, I am little more then let down. Every step of this conversion has been a genuine hassle, requiring much R&D, and a lot of struggle. Now, It runs great when parked, but the clutch will not disengage . I am using the south bend con ofe, and I just don't know what I did wrong. I had the flywheel resurfaced, and I have looked to check to see the slave cylinder work, and it does. Please let me know what could be wrong here.



Thanks a lot,

Russell

 

[MikeO]

Are you getting stock like resistance when you push the clutch in or does it feel like mush?



If it feels like mush, then you have air in the line (easily solved).



If it feels like stock, then we need answers to a bunch of questions like:

What did you use as a clutch?

Did you/somebody else test for disengagement on the bench?

Are you getting ANY disengagement when you push the clutch in?



I hate to even suggest this, but the only way to test the last question is to drive it. Normally, that will require rigging a relay to start it in gear (it will easily do this in first on a flat surface) and being comfortable shifting without a clutch. Since you have at least partial engagement with the clutch in, just start it with the clutch in and nothing/nobody in front of the truck. If you are up to it, try driving it in something like third and with the clutch in apply at least half throttle. If the revs rise (meaning the clutch is only partially disengaging) then you have found your culprit - a partially disengaging slave cylinder. This could mean that you don't have enough throw, it is mounted wrong or a bunch of other stuff.



Let us know and as usual, if you try this you try it at your own risk!



Mike O.

 

[83 crew cab]

I had truble with mine the slave cylinder was out ok wack so I had to compress or extend it not sure with any more then it will reset it self with a couple action of the peddle I am sure now that I am thanking you hav to compressit the thew out bearing just touches the fingers Geroge

 

[R.E. Miller]

This is what I have noticed. I took the rubber boot off of the area where the slave cylinder runs the linkage to the throw out bearing. When some one stomps the clutch to the floor, you can watch the bearing and linkage work in and out. The slave cylinder will push the until there is only 1/8" of clearance from the linkage and the bellhousing. My fear is that since I don't remember what the measurement was for the bearing retainer on the NV4500, it is too long and is pushing the clutch disk slightly into the flywheel, eliminating the chance of disengagement. The sad thing is I hope for this. I really don't feel like pulling this whole thing apart, but if that bearing retainter isn't holding the clutch in, I'm lost. I will be calling south bend, advanced, and standard transmission tomorrow to try and get to the bottom of all of this. I didn't worry about the bearing retainer too much because they said it was machined to the right tolerance from their shop, but I did have to machine my bellhousing to get the transmission to fit, so this is anyone's guess



Thanks again, and I'll let you know what I find out,

Russell

 

[83 crew cab]

yea going by advance adapters paper work you have cut about a 1/4 inch off not sure off the measurement off hand, you all so have to make sure you have the right ( long splined input ) input shaft if not you can change the shaft with out taking the transmission completly aport George

 

[R.E. Miller]

After thinking about all of this, I am almost certian that the bearing retainer is too long. My transmission has the fully splined shaft, so I should be good to go there. I just hope that I did not destroy the clutch disc when I torqued the transmission up against the bell housing I'll se what I can find out today.



Russell

 

[83 crew cab]

not sure if I was clear last night the spines I am talking about are under the bearing retainer George

 

[R.E. Miller]

I understood, because that was something I worried about when I first started out with all of this.

Russell

 

[Bob Beauchaine]

The first thing I would do is call Peter at SBC. I had the same problem after installing my SBC and pulled the whole thing apart and measured everything - everything was right on spec. ???? I finally called Peter and he said that it sounded like hydraulic's to him. I tried 2 new slave cylinders with no luck. I finally went to the "stealer" and got a new clutch master/slave cyl combo - cost was about $320 but it sloved my problem. I think the old setup was just worn out. BTW the pressure plate I got from SBC was the same LUK p/n as I took out. Peter knows what he is talking about and is more than willing to help. Good luck.

Bob

 

[MidwestMotorman]

a tip?

You might be able to check whether it is the retainer or not by using shafts of threaded rod in place of the bellhousing bolts. Screw them in one at a time and take out the next one. You may have to loosen the trans mount to let the whole works slide a little to the rear. This will let you gain freeplay and see if more clearance is needed. Perhaps the stock bolts are long enough to back out without worry of separating the assembly. You may also want to put a jack under the trans to maintain correct angles and keep the input shaft in line with the crank.



This is just an old trick used by tractor mechanics when seperating tractor drivetrain parts. You may also want to set the rear end on jackstands as this will prevent any truck movement, and you can turn the rear wheels to check for disengagement.

 

[R.E. Miller]

Thanks for your pointers!

Well, I just started my new job as a diesel mechanic's assistant , and I have yet to get enough time together to tackle my truck. But I did talk to peter at SBC, and I talked to the good dogdge dealer nearby, and they seemed to think that the hydraulics were not the problem It looks like sunday may be the tear down day, if I can't figure out anything else.



Thanks,

Russell

 

[JTMcCracken]

R E Miller, When I bought my kit it came poorly packaged, the trans had tipped over & dumped most of the fluid, and no instructions, Advance Adapters has a very complete set of instructions concerning the front bearing retainer modification and input shaft change, however I bought the kit from another company and they didn't send any of this. I had the same problem your having, e-mail me if you have any questions. JTMcC.