Community Forums

Bigd9 · 08-03-2016, 10:46 AM

Not an immediate problem, just darn annoying! I usually clean mine every other year just because that way I can check for other things at the same time, and I can clean my rims sitting in the living room watching TV! So once every other year my rims almost look as good as Fire Up's does!!!

FIRE UP · 08-03-2016, 10:48 AM

Quote:

Originally Posted by corprimo

I've had a "clunk" from front end when coming to a stop for a while now. We're heading down the "Highway" from AK to Portland in 5 days. If my problem is the S cams, do I need to tackle it before this trip or can it wait until we get down to Oregon? How hard is it to pull the brake drums - do they have to be knocked loose with a BFH?

corprimo,
The component parts of air brakes, inside the drums, is not complicated. It's no where near what you see in most conventional braking systems. But, based on the stress on each component and, the fact that they operate in predomenently one of the harshest environments possible, they get corroded, rusted, grunged up with dirt, brake dust, debris, rust and more so, some of these components just get "stuck" and won't move even the short distance they're supposed to.

So, removing the wheels and drums is what's needed to get at these components. Now, first off and, of primary importance here is, HOW SCHOOLED ARE YOU in messing with ANY brakes? If this is all new to you, then in reality, you really should, at the very least, have an experienced person with you while this operation is performed. If you are tech savey, then no need for the warnings here.

You ask if you should tackle the S-cam situation before your trip, most likely not. The "clunking" primarily happens, or at least you can actually hear it happen, with slower driving, city streets, parking lots, slow maneuvering situations. Your brakes will still function for your trip.

Do you have the means to break all the 450 ft. lb. lug nuts loose? Do you have the means to re-torque them to the proper settings? And, more than likely your shoes are properly adjusted so there's a close proximity to the drums which, means the springs are stretched some etc. And that means they won't loosen to get the S-cams and related components out until you manually back off the slack adjusters. Do you know how to do that? And, conversely, do you know how to manually adjust them back to the proper brake shoe to drum clearance?

And, even when the lug nuts are removed, handling a 140 lb. tire and wheel as it comes off the lug studs is, to say the least, seriously cumbersome. The tire/wheel dolly shown above is the really, only way to goof around with those heavy tires and wheels.

These are just some of the things that are needed to know before taking on this project.
Scott

jelag · 08-03-2016, 11:42 AM

So I have one comment... and there were several very good suggestions... Remember that when brakes are changed on a truck the spring kit is usually always replaced... and in most cases they are put together dry.. but these units are on the road daily... I personally wouldn't be afraid to use some light never-seize on my parts...

Here is a suggestion... chock the wheels... have someone touch the brakes and watch the slack adjuster move... the end of the slack should move about 1/2" and that's about it... remember that when the slack adjuster and S-cam connection should be at a 90* angle when the shoes contact the drum... this supplies the best possible torque to the s-cam... in addition... the spring brake has limited amount of movement to function correctly.... you can over stroke it... that's the second reason the movement of the slack adjuster should be about 1/2" when the shoes contact the drum...

And my last thought... is that all self-adjusting slack adjusters can be manually adjusted.. I'm often not happy with the way the slack self adjusts.. I like my brake pedal a little tighter... so I adjust them to suit my preference....

Remember, keep the s-cam, roller, brake shoe contact points and spring clean... if you have an open brake drum... don't be afraid to put on a dust mask and spray out the shoes, drum and parts from the inside of the frame to keep the dust and dirt out...

jimbo2013 · 08-03-2016, 01:34 PM

I'm going to disagree, when I did mine they were bad, but still worked or so I thought.

After doing them it was like half the stopping distance.

dustyone · 08-03-2016, 02:07 PM

I would think it would be a bad idea to play around with brakes. Best thing you can do is get him looked at right away. May save you a lot in the future. If it's a clunking it could be anything from the S cam 2 its bearings 2 spring adjustment to the actual brake shoes themselves or even a worn-out drum playing with yourself on the steering is not a good idea because of the seals and the bearings that need to be adjusted and what you think or perceive as a break could actually be the bearings get a professional to look at it cheaper in the long run... Dusty

dustyone · 08-03-2016, 02:08 PM

. Supposed to say playing with it yourself is not a good idea oops

jimbo2013 · 08-03-2016, 03:09 PM

it can also be a broken part like spring retaining clip, etc.

My clunk noise was just the parts rusted or gummed up sticking and not sliding or rolling until tremendous loads.

FIRE UP · 08-03-2016, 03:46 PM

Quote:

Originally Posted by dustyone

I would think it would be a bad idea to play around with brakes. Best thing you can do is get him looked at right away. May save you a lot in the future. If it's a clunking it could be anything from the S cam 2 its bearings 2 spring adjustment to the actual brake shoes themselves or even a worn-out drum playing with yourself on the steering is not a good idea because of the seals and the bearings that need to be adjusted and what you think or perceive as a break could actually be the bearings get a professional to look at it cheaper in the long run... Dusty

"Play around with brakes"

I don't think anyone's suggesting to "Play" around with brakes here. We're suggesting courses of action to take, if problems/issues are felt/seen/observed and, what many of us have done, to oleviate the "clunk".

the S cam 2 its bearings 2 spring adjustment

Not sure what "bearings" you're speaking of and, also not sure of the "spring adjustment" either. And "2", I guess you mean TO.

Brakes, as we all know, are not something taken lightly. If doubts exist in terms of capability in working with or on them, then of course it goes without saying that competent techs should be sought out to either help with the work that needs to be done or, just have them do it.
Scott

corprimo · 08-03-2016, 09:25 PM

Thanks for all the advice and cautions. I'm not one to dive into the deep end, so I didn't go much further than wire brushing and blowing out debris. First problem was breaking loose lug nuts a tire dealer in OR had installed. I bent the 30 inch bar that came with our Winnebago with my 4 foot cheater (with my wife's help, I might add...) so drove over to a place I had always wanted to check out - FUBAR Trucks and Heavy Equipment in Wasilla. I mean, what kind of person would name his business FUBAR? Charley is his name, great guy, and tons of experience. He had to break out his 1 inch impact tool with an air hose about 1.5 inches in diameter to get some of those lug nuts loose. He was more concerned with the right rear brake that always tends to stick after the coach has been parked for a while, and it has been getting progressively worse. He crawled under with a flashlight and told me brake shoes were shot on that side, but in good shape on the other rear. So he went right at it without an appointment, and an hour and a half later I had new shoes on the right rear and my front lug nuts loosened up a bit. $90 for parts, $210 for labor plus shop supplies. Up here in AK, that's reasonable. I got home and pulled the right front wheel/drum - cleaned it up as well as I could with a variety of wire brushes, blew it out good, added a little grease to the zerk and put it back together. It looks pretty good to my amateur eye. I'll do the left front tomorrow and then road test it. We'll see if the gentle "clunk" is still there. And I heartily recommend FUBAR! If you don't know what it stands for, you're too damn young! Thanks again for all the comments.