The Stovebolt Site Forums The Parking Lot Big Bolts Left Rear Brake Jammed up on 4100 please help

Got my 50 4100 1.5T with 2300 original miles running great, but I can't drive it with no brakes. I need to replace both rear wheel cylinders, but I an out of ideas as to get the left rear drum off. Got the 2 adjusters backed off, but the drum appears to be jammed in place. I can get the truck to move a couple feet back and forth using a lot of power just to move it, then it just locks up. With the rear off the ground, the right wheel spins easily, but the left one I can barely move by hand a little bit, with a lot of drag, then it just stops. Maybe a lining came loose, or a spring? I have no idea how to proceed without destroying something.

Unbolt the wheel cylinder(s) from the back side of the backing plate and disconnect any other lines, brackets, etc. that you can remove. That might create enough slack to work the drum off the shoes. Some heavy duty brakes use two single-acting wheel cylinders, one for each brake shoe. The shoe hold-down springs that keep them pulled against the backing plates might have to be cut off with a die grinder, but only do that as a last resort- - - -it might be hard to find replacements.
Jerry

So did you remove the right rear already ? Have you tried spraying a lubricant like WD 40 between the backing plate, and drum lip, or anywhere else you can get it in there ?

Made a little progress today I think. Using 6 wheel chocks, and a jack stand. I worked the stuck drive wheel back and forth for 30 minutes. Running high idle using the clutch between reverse and first, trying not to roll it off the jack stand, I started getting a little more movement in the reverse direction and at it I finally got it to rotate pretty easy with the engine at low idle with the clutch engaged. If I try and run it forward it jams right up. Felt everything around the drum and hub, and everything was still cool. It will be interesting to see what's going on when I eventually get the drum off?

Many repair shops have reference to casting numbers found on wheel cylinders, so when you get them off see what the numbers tell. Always best to get new loaded cylinders if available rather than refinish old ones, if possible.

Ed

That was a relief, the brake drum came right off after getting it free, I think the issue is the left half of the wheel cylinder had trapped pressure on it from the right piston that seems to be stuck. If I would have just loosened up the bleeder it probably would have retracted. If you look closely, I cracked the left brake lining near the top. The brake linings look pretty cruddy and barely worn, but will probably get re-lined at some point. The brake drum shows almost no wear either at 2300 mile. I'm also wondering if the brake spring is backwards or something, since it kind of bows, and drags over the parking brake linkage?

http://oi64.tinypic.com/xap9c9.jpg

Since I have to wait for wheel cylinders to arrive, I decided to make it easier to deal with the spindle nuts since this won't be the last time I have the rear drums off. Ended up finding a 6 lug spindle socket at Blain's farm fleet. It's a Powerbuilt 6484745 2 5/8 OD socket for $16.95. I had to take a parting wheel and shave the lugs down on the inside and narrow them slightly until it finally snapped right into the slots of the spindle nuts. This will work much better than a hammer and a punch,.

That spring looks pretty normal- - - -a little drag in the middle isn't really going to hurt anything. Huck brakes on a big rig- - - -"Interrrrrresting!" Don't trash the old wheel cylinders- - - -they can be machined and sleeved even if they're badly pitted, and a stainless steel sleeve will last forever.
Jerry

So, are there any casting numbers on the cylinders?

Ed

Haven't looked yet since the wheel cylinders are still in place until I get new ones, but they have been replaced before because I see it says Wagner on the casting.

I think I've found the issue on my LR Huck brake hanging up as soon as I pulled the right drum off, and saw the return spring which was much beefier than the other one. Got a new one coming, but since I have to pull the left drum off again I think I will have the shoes relined that have been soaking up brake fluid for years. The brake drums have no wear on them. Just need to figure out how to remove the retaining clips for the shoes. Looks like pulling the whole assembly off the backing plate would be the best way to get at the clips on the backside of the shoes. Also need to find a brake re-liner hopefully near northeast Iowa? Thanks for any tips.
Update, found a local company than can get the linings redone for me at another one of their facilities. Just need to get them off, and drop them off, and wait.

Got all of the shoes off pretty easily, and all of the links and pins and the small spring loaded pins, whatever their function is. Seems like you could just use a bolt there? Also wouldn't snap rings be better on the pivot pins for replacements than the soft bent up original ones? I think I can re-use the original ones just fine. Dropping the shoes off tomorrow, but have no idea as to the cost, or time. Does anyone have a recommended lining material to request, or which is better, riveted, or bonded?

Got the rear brake shoes back 5 days after I dropped them off, and it came to $238. They look like new with bonded linings, and the service was great. I'm glad I marked all of the shoes, and links to make assembly easy. Still managed to get one on wrong anyway. Never needed brake spring pliers before, so I tried the $10 ones at Blaines, and they folded up on the first return spring. Got a Lisle for $24 and it worked like a charm. The rear shoes adjusted right in, and now it's on to brake bleeding and the truck should be ready for it's first voyage in over dozen years, or more, if the front wheel cylinders don't leak, or I'll be going to end up doing the same I did to the rear. Changed the old black gear oil in the rear, and transmission too, but wasn't fun laying under the truck pumping over 2 gallons of gear oil by hand.

If the rears were bad, might as well do the fronts, too, while in the mood. Then you will know they are all good.

Ed

Got the brakes bled and have a firm pedal at half travel. Set up a remote fill bottle on the master cylinder, and used my compress air-powered vacuum bleed which works great working by yourself. Pulled 2 quarts of brake fluid through the system in less than 30 minutes. I spun and pulled on the front hubs to check the bearings, and the right front moved in and out a 1/4 inch which didn't seem like something I wanted to see. Pulled it apart and all the outer ball bearings fell out of the cage, which the out half had worn off after looking at the good side, and the inner bearing race was bad too. Good thing I pulled it apart because both front wheel cylinders are leaking too. I think the shoes will be fine for now. The fun continues and I don't need to call the insurance company for another week now.

Good decision.

Ed

Ouch, the only inner wheel bearing I've found so far is a tapered replacement for $154! The outer is only $21.95. Anyone have a better option on the inner bearing?
Also I don't know where to look for the tang washer under the spindle nut? Mine looks pretty bad since it looked like all of the ball bearings were riding on the backside of it, and wore a new bearing race right into the face of it.

I figured out why the RF wheel bearing failed. Someone managed to put the outer bearing on backwards, because the inner race of the outer bearing was still on the spindle when I pulled the hub off, which left only the washer riding on the outer part of the bearing. I actually had to pull the inside small race for the outer bearing off the spindle with a puller. It had over 3/8ths play in and out. I don't think it could have run another 50 miles without destroying the hub and spindle too, or just fall off. Glad I didn't try to put it back together the way it came apart. LF bearing is fine, and was installed correctly. $300 worth of parts on the way!

I would imagine looking for another spindle would be quite the hunt. Good thing it didn't get destroyed.