Over the weekend I installed my South Bend 13125-OK, and after getting it back together my clutch will not engage.

I can tell you the mistakes that could cause this that I definitely did not make. 1st I did NOT install the disk backward, I did NOT install the clutch fork upside down, and I did not press the clutch when there was nothing acting against the cylinder.

The clutch actually does not seem as stiff as it should be, and seems to have a bit too much play at the top. There is plenty of fluid in the reservoir and I was wondering if air got in somehow, so I took the slave cylinder out of the bell housing and pumped it about a hundred times by hand with the cap off and the line in a vertical position in attempt to bleed it. I then pumped it another hundred or more times from the pedal once it was reinstalled and I really saw little to no improvement from all that. Any ideas? Can the slave cylinder be overextended and damaged by sitting with no load on it?

 

never heard of that, I would try bleeding again- vacuum bleeder or something similar would work better. Remember, you should have the bleed screw open when pressing the pedal but closed when releasing the pedal even if the tube is in a bottle of fluid air can infiltrate through the threads of the fittings.

 

It's a closed system, trying to bleed it is a waste of time. Internally a check valve is worn out or failed. I just had the same problem, installed a new SBC and the clutch will only disengage with the pedal to the floor and engages less than an inch up. I can't complain, this linkage lasted 365k miles. I ordered a new hyd clutch linkage from mopar4less. If you need a heavier,adjustable linkage SBC sells one, just more $$$

 

Well my local Dodge dealer wanted $290 for new hydraulics and they were a day out, while I was able to find a local retailer that had the South Bend one for $310 in stock! My decision was easy, so I've got the SBC hydraulics now, and I'll never look back. Now it's time to install it.

 

Well the clutch feels right now, but it still doesn't disengage. Gotta take it apart tomorrow and figure it out.

 

My truck was at a buddy's house when I was doing this work, but I drove it home tonight rev matching between gears to get here. I'm going to drive it to work in the morning and get off early and drop the transmission again to take a look.

 

Well the transmission is out, and the problem is not apparent like I thought it would be. I've been working over the phone with Texas Diesel Shop, who was the retailer, and they have been working with the peeps at South Bend. All involved parties have been extremely helpful, and I am very appreciative of that.

I put the bell housing back on and had someone actuate the clutch while I watched, and I stuck my finger in there and could not move the disk. My next step is to remove the flywheel and bolt together the assembly and activate it with a hydraulic press and see if it disengages, that way I know whether or not the clutch is the culprit, or if something else is.

 

Don't you hate it when a plan doesn't come together? I wish you luck on this. I am 90% into converting to a G56, thus the new SBC with a smf. Since I can disengage the clutch with the pedal to the floor I am 99% sure it is the hyd clutch linkage, but will feel a lot better when I get it installed and the pedal works correctly.

I know that SBC is a standup company and will back their products 100%.

Are you dealing with Texas Diesel in Madisonville?

 

Yes.

 

It is almost 3:30am and I just got done driving the truck after getting it back together. I took the clutch assembly to my buddy's machine shop and put it on the hydraulic press and actuated the pressure plate and it released the clutch, so for some reason my setup wasn't pushing it far enough.

I added another washer to the pivot ball in the bell housing and installed it again and got someone to press the clutch while I monitored it. It actually disengaged this time, although only about 1/2" off the floor. I installed another shim, and this time it disengaged about half way to the floor. I put it back together and it drove just like it should. I have NO idea why I had to do this, but this is what I needed to do to make it work. I even inspected the clutch fork and it looks just fine. I will call Texas Diesel Shop in the morning and tell them they can consider this case closed... hopefully they won't freak out about my unorthodox solution. I'll agree that it's kind of a band aid for whatever the cause was, but I need my truck!

Anyway, the clutch is a SBC 13125-OK, the low man on the totem pole of SBC 13" models. I noticed that it grabs well enough that downshifting to slow down causes the rears to lock up if you don't ease the clutch out. Something I never experienced with the stocker.

For the record, I will probably never do another clutch job without 1st installing the bell housing and checking clutch disengagement if at all possible. Doing so would have saved me probably about 15 hours of labor in total.

 

Just for giggles, how much did they shave off the flywheel?

Almost sounds like they cut more than they should have.

 

It was a new flywheel that came with the 13" clutch.

 

Man, then that's a toughie. Just went thru the service manual, and the clutch pivot ball is not adjustable, the only thing it references is wear on the pivot ball or fork, might not take much to cause a problem, but I would also think you would have seen it with the old clutch. Are you sure the new slave is completely seated on the bellhousing?

In any instance, I would not get too excited about your unorthodox fix, the geometry has to be right or it would not release correctly.

 

No the pivot ball is not adjustable, but South Bend sends a washer to shim it with with the clutch kit. It was definitely not worn, and I just followed their lead and added more shims. Yes, the new slave is completely seated on the bell. The nuts are torqued to ~25ish ft/lb.

BTW, the clutch releases and engages beautifully! It engages like a factory truck, just a little bit more grabby. What do you mean the geometry has to be right? The throwout bearing pivots on the fork to always be fully engaged with the pressure plate, regardless of the angle of the fork.

 

Yes, that's what I mean, there isn't a way to get the geometry off, so if she works, the geometry has to be there.