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Ongoing clutch fork issue. Has anybody ever seen this?

Hink

Overkill Is Underrated
Messages
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Location
Stevenson, Wa.
Hey guys, it's been a long time. Happy freedom day! Well, every day is freedom day, but happy one any way. I've been crazy busy for the last several months and have only had time to check in a few times.

I've been dealing with an issue that has finally demanded my attention that I hope you all can shed some light on...

NV4500 transmission, Southbend clutch.

Trans, clutch, fork, T/O bearing, ball pivot, clutch master, slave, and line ALL brand new

Until last year when I put my transmission in, I had never done any tranny work. I don't know why, I thought it took special tools or something (it does to get in the innards, I know) so I had a shop do my clutch work. Well, it's never been right since then.

The main issue was that the clutch fork was rubbing on the ribs of the bellhousing. Has anyone seen this before?

It could be one of three causes that I could think of...

1 - The ball pivot could be worn so much that it caused the whole fork to be closer to the bellhousing. The guy said he replaced it (supposedly) but after only about 6 months, it was wore all to hell so I replaced it (again) when I put the new tranny in. Yes, I lube it regularly.

Or it could have worked its way back on the threads, but it can only move a 32nd of an inch or so until it stops on the front of the tranny.

2 - The throwout bearing could be worn/installed incorrectly. But it was new and I know how to install it.

3 - The clutch fork itself could be incorrect. I actually thought that I had found the issue when NAPA got me one that looked like it had been clearanced from the factory at the spot where it was rubbing. But using that fork didn't solve it.

The result of all this is that after only about 6 months, I started feeling some interference when engaging the clutch and with the added pressure from that interference, the clutch hydraulics blew (again).

I was forced to do what I really didn't want to do and that was clearance the ribs with a Dremel. I really don't like grinding on anything that shouldn't need to be grinded on and certainly not in a spot that is supposed to be strengthening something.

Here are the photos, I hope someone has a solution!

Fork and Housing with explainationWatermarked.jpg Very worn forkWatermarked.jpg After clearance topWatermarked.jpg After clearance bottomWatermarked.jpg
 
Is there any adjustment or way to shorten the max stroke of the slave?

I am guessing the clutch is well disengaged by the time the fork hits the rib but since your foot still travels it just binding on lastbit of pedal travel and spiking hydraulic pressure. ????
Nor do you feel interference during disengagement ????
 
No adjustment that I know of.
Yes, I could always feel some interference.
I'm hoping that the last bit of clearancing will solve the issue but I'm wondering what was going on in the first place?
 
You have a Southbend clutch. Call and ask for Peter (574) 256-5064 as they have probably seen this problem before.
 
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