I got my bus out of the repair shop for the brakes at 7:30 pm last evening. We are now in Kansas City, KS and the tag axle brake is hung up. Smoke started pouring out of the tag axle brake and we pulled over. It is obvious the brake is hung. The shop replaced the brake chamber on that side.
I would appreciate any pointers on a place to get this repaired. The after hours guys at the place that did the repair in Minneapolis won't help me until the day shift starts at 7 am. They would dispatch someone if I was local.
My phone number is 612-508-9956 if you can help. I'm going to go out and take a look right now and see if maybe I figure something out.
Is it a combo brake (service and emergency) or just a single brake chamber?
Disk or drum?
Drum brakes. Just service since it is tag. (I was just under the bus.) I was incorrect on the shop replacing the tag brake chamber. They replaced one of the front chambers. They did work on the tag brakes.
I chocked the bus and had someone step on and off the brakes while I was under there. It appears both brake chambers on the tag are working properly right now. I suppose it could have cammed over. We were barely using the brakes and no hard brake applications. There is plenty of shoe left.
I'm not sure what to do right now. I don't know if I should try to drive it again or not.
If it is just a service brake and you are concerned about overtravel you can temprarily disconnect the hose to the brake chamber and cap or plug it. If that is not practical you can remove the hose, stick a dime in the end and reconnect it and that will restrict the air flow enough so it should not over travel.
I know you are getting beat up over this, but you now realize no matter how skilled the mechanics they don't care about your coach as much as you do. So for your own piece of mind work with the mechanic just to verify your brakes are working correct. As to over travel you should be able to see the S cam and determine if that is happening but unless your shoes and drums are really worn I would not think that is happening. Are the return springs connected and in place?
Some tags do have combo brakes. My tag axle has 16/24 chambers, a very hard size to find.
My driveway rises 80 feet in a 285 foot length so you can see that brakes that work correctly are kind of a special concern for me. They are not difficult to understand or repair.
I might have read this wrong but I will ask anyway. Were you just tooking down the road for a while and then smoke started coming out? Or did you just get started and within a mile it happened? The reason I asked this is I missed seeing the red light on my dash, indicating a brake was still on. I was able to drive it about a half a mile and we started smelling the brake. We were in very cold weather so I assumed it was frozen.
That part where you just started seeing smoke drew my attention and got me to thinking.
We had driven some 400 to 500 miles before this happened. I don't have a light on the dash that indicates if the brakes are actuated.
I thought about disconnecting the air to that brake as a temp fix, but if the chamber seems to be operating properly now so I'm not sure that would help. Time to go underneath again I guess.
I looked at things again. The brake chamber is moving, but the s-cam is not. The shoes are definitely still contacting the drum.
It looks like I am going to need a tow or a mobile mechanic. I am still waiting on a call back from Coachnet to see what they suggest.
do you have a tag lift?
With spring brakes, and particularly on an Eagle without air suspension, any decent truck shop should be able to handle that job. You don't need a bus garage.
Quote from: robertglines1 on September 01, 2011, 04:46:30 AM
do you have a tag lift?
No, the tags are not liftable or steerable unfortunately.
I'm not planning on looking for a bus garage.
can you get to s-cam with any thing(pry bar-hammer&drift pin) and rotate it back. wonder if it was greased? might actually try that. or just tap on what you can see and it might release. or grease and rock back and forth. just some thoughts. try any you haven't thought of
I really feel for you Brian. I wish I was closer I could come help. I would listen to Bob, get under there and smack that cam with a hammer, and try to get into a truck stop. Probably just dry of grease.
Brian,
Give me a call. I just left my number on your phone. I am somewhat local, and might be able to help.
John
Had the brakes been applied recently before they set up? If not then the brake chamber may be getting air sent to it from a bad valve somewhere like if the brake pedal had been depressed for several miles. You could pull the air line to the chamber to see if this is the case.
If the brakes are cammed over, you should be able to release the cam with a pry bar. If this is the case, be careful that they don't cam over again. You could try to back the slack adjuster off and see if that releases the brakes. If you need to move the bus, you should be able to jack up the axle to get the tire off the ground and chain up the axle. That will get you to a shop.
Helps coming Brian, hang in there.
I was reading the other thread about your brakes. This is exactly why you need to know how to play with them yourself. Good luck.
It is hung if the push rod is moving back but the shoes are not. Take a large hammer and hit at the housing that encloses the shaft for the s-cam. Little by little it should begin to release. Then close off the line by any number of ways.
This is the kind of thing that can be prevented by backing the brakes all the way off and manually exercising the s-cams by pulling the slacks numerous times while backed off and greasing the camper.
I eluded to this somewhere in a prior thread.
A properly adjusted manual slack and properly working autoslack barley moves and over long periods of time form a dam or ridge of grease and grit. Backing the s-cam all the way out before greasing rotates the shaft almost 180 degree and puts grease on the backside of it and keeps things much better much longer. It keeps the face of the s-cam where the rollers for the shoes ride cleaner and smoother less apt to hang as they begin to approach their outer limits.
If you get a big enough hammer and get a good enough hit on it it will free up guaranteed
Jack it up and be sure you didn't have a wheel bearing go out
good luck
You can't chain up the axle on an Eagle, but you pull the wheel off.
The more I read, the happier I am I dont have tags. Just more crap to put you on the side of the road and empty your wallet, lol.
Do I understand correctly that you could chain the wheel up off the road, tire and all and drive a ways??
I just left you another message, Brian. Give me a call.
John
What Clifford said. I was 100% convinced I had a tag axle brake problem right up to the moment I realized the inner bearing was no longer with us.
Quote from: bobofthenorth on September 01, 2011, 06:44:59 AM
What Clifford said. I was 100% convinced I had a tag axle brake problem right up to the moment I realized the inner bearing was no longer with us.
I agree with Clifford and Bob. I was going to mention that when we chatted again. That is also something that I would like to check.
However, he said that he doesn't see it working, like the other brakes. We didn't get into a lot of specifics. I have no idea what kind of tools they have, or anything like that (I don't even know if he knows what parts we are talking about, or if he knows where the cam housing is, hopefully I will find out).
They smelled burned brakes, that is why they stopped. They are on a off ramp, just south of downtown Kansas city. BK gave them some ideas, then told them to chat with Arrow. Arrow told them to tighten the slack all the way up, then step on the brakes as hard as possible. One of the guys, who was standing out next to the bus, said that he heard a pop (or something). But Brian said that it still wasn't "working like the other brakes."
I should know more when they call back.
FWIW
John
Lets pray its not a bearing, he dont need that kind of grief.
For future referance. On any hub, when the rollers for the shoes begin to rest at the outer ends of the s-cams when adusted up two things are occuring. Either the linings on the shoes are not as thick as you think they are but rather are worn AND/OR the drum is getting worn.
Back when I was trucking I would put 2 or 3 sets of shoes before replacing the drum. When you do this the 2nd and 3rd time around you can "cam-over" without even hanging. The drums get so far out it all happens with still 1/2 or even more than 1/2 the linings still left. So when you look up there and see tons of lining left then look further, to where the rollers are sitting on the cams. They should be sitting in them real "tight", if not the drums are worn.
The drums on these buses are way way bigger and heavier than truck stuff at least our XL components are.
If I had to guess it is either worn shoes or my first choice, the bus does not get used enough. Probably u got good stuff and is taken care of well the thing sets too much like most of them ours included.
On a bus with air suspension there are a number of things you could do, including chaining it up high before you air it up. The eagle, as I understand it, has torsion spring suspension so you can't get it very high at all with chains. Taking the wheel off, jacking the brake drum up to a normal, non-droop position and chaining that would work, if there is a way to chain it at all and it you happen to have a chain...
I think tags just go hand in hand with a 40' bus, and most every bus you can get these days that was built after 1980. Yeah, more to go wrong, more to maintain, but the extra 5 feet and the newer bus seems to be worth it to most.
I wonder if the return springs on the shoes have broken, been replaced wrong, or similar. My first thing would have been to disconnect the push rod from the slack and see what the heck was jamming, I think. This is a tough one, I would hate to have to deal with this in a parking lot or worse, the side of the road.
His bus is Torsion suspension only the tag is air I just cannot believe it doesn't have release valve ,I feel for this guy what can go wrong does with him
good luck
He is rolling, guys.
He talked with Arrow again, and they said since he heard the pop, the brake should be released. When I first talked with him, he said that they hadn't tried moving it since they tried releasing it.
The brake is now released, and they are moving now. They first pulled of at the 18th st expressway exit (that area) on I-35. Now they are rolling, and I think he said they just pulled of at highway 7. I mentioned that Crossroads was in that area, but it sounded like they are heading towards another shop down there.
Bottom line is, he should be set. I was ready to go down to get them rolling towards the shop, but they were set before I left.
Thanks for the help and advice, gents. I know they are grateful.
Awesome news.
Ill tell you whats hanging Brian and It also was the POP they heard. It was the roller for the shoe hung way out close to but not completly at the end of the "s" in the s-cam.
So the trick here is to NOW go around to the other brakes and hubs, all of them. Even if you have automatic adjusters. Adjust up all the other slack adjusters tighter by about almost half or so of their current travel. That will reduce the application pressure on the one thats hanging and probably keep it from happening again till you get in.
Thats what Id do.
The application pressure in an air brake system is strictly related to a couple of things, aside from basic sizes, friction material, etc. as I understand it. If I'm wrong I'd like to learn, hence this post.
There is a variable leverage effect on the brake shoes relative to the position of the S-cam against the rollers, but it's minimal. Leverage is greatest at the base of the S-cams and less at the tips, so as the brakes wear and the rollers move out, leverage and efficiency drops. This is accommodated within the design of the air brake system, where you can simply apply more air pressure to compensate. Adjusting the slack adjusters does not change the position of the S-cam relative to the rollers, that is strictly a function of brake shoe thickness relative to brake drum inner diameter.
The thing that adjusting the slack adjusters does is change the leverage ratio of the push-rod to the slack adjuster. Within the range of adjustment the difference in leverage ratio is only one or two percent, so again close to irrelevant.
About the only thing that does change the pressure developed is air pressure and cannister size. That completely overwhelms the other possible differences. You develop a certain amount of pressure in the system that is delivered equally to all of the cannisters, and they develop push based strictly on their size. So adjusting the slack adjusters, which I might do if they were manual but would not do if they were automatic and in range, won't actually do anything to change the amount of pressure on any of the brakes relative to the one having a problem.
Now what you could do is just disconnect the pushrod from the slack and let the cannister fully extend as soon as the brakes are applied, or adjust that slack to be very loose, so the can bottomed out as the brakes are applied, the idea being that you don't have a way to disconnect that can and you don't want it to cam-lock or cam over again. Making that one brake ineffective won't affect any of the other brakes at all.
If this is wrong, let me know in what way so I can correct my thinking!
Brian
I talked to Bryce and he directed me to Arrow Stage Lines in Kansas City. They said they could send someone out to look at it. But first, the gentleman told me to try tightening the slack adjuster all the way and then doing a full pressure brake application. He said that frees up stuck brakes 9 of 10 times. That seems to have worked.
Now that the brake is freed up I need to find a place to fix the problem.
Don't mix up brake application pressure and volume.
If you step on the brakes you are essentially telling the system how much pressure the brake chamber is going to see, not how much volume it is going to get delivered.
All a long stroke does apart from running the risk of overtravel on the S cam is lose mechanical advantage. The volume of air delivered is that which is required to provide the pressure you called for with your foot. The greatest mechanical advantage comes from properly adjusted brakes and when the slack adjusters are adjusted all you are doing in essence is rotating the S cam, bringing the shoes closer to the drum, while positioning the arm on the slack adjusters so its travel is in the range of greatest mechanical advantage.
Yes inevitably the applicacation pressure will equall out but making all the other brakes tighter will have them grabbing first or quicker and that will give some "cushin" to compinsate under normal braking. If you have to make a panic stop all bets are off.
Or if a maxi is doing this every time you set the parking brake it may hang up again.
On trucks they have appplication pressure gauges and brakes that are adjusted tight require way less application air to stop. If good 10 lb of application air will stop you nice. If a truck is loaded heavy or say a panic stop you get to 60psi or so of application air.
I do not disagree with anything you mentioned Bri
Quote from: belfert on September 01, 2011, 09:08:03 AM
Now that the brake is freed up I need to find a place to fix the problem.
Ummm, Brian. You told me that you were stopping to get it fixed right away. There is no way, you should continue like it is.
Think about it like this. Say you are driving. You have a panic stop to make. You don't make the stop and either injure or kill somebody. An investigation ensues, and it is discovered that your one of your brakes is compromised. That could be real trouble!
It is one thing to bypass a brake until you get to a city. But I really don't think too many people will have much sympathy if a brake is bypassed, and you continue driving until you get out of town.
I would have been MUCH stronger on the phone, if I would have guessed that you were going on.
Some of the gents on here might disagree with me, but safety is a big concern.
FWIW
John
All of these suggestions are fine for solving the immediate problem and getting underway again. They do nothing for the underlying cause which is lack of proper maintenance.
You cannot inspect brakes from the back. The only way to be sure is to pull the drums on every wheel and thoroughly inspect and repair every part of the braking system, including drum diameter and roundness.
If the tag brake overheated enough to make visible smoke, there is a good chance that the linings were damaged, the drum was warped and/or the bearings and seals compromised.
You were very lucky to see the smoke. If it had happened at night, you might not have discovered the problem until it was flames.
Quote from: Len Silva on September 01, 2011, 09:58:53 AM
///////////snip////////////////
You were very lucky to see the smoke. If it had happened at night, you might not have discovered the problem until it was flames.
Len,
Brian said that they smelled the brakes. It was dark, when they figured out they had a problem. He had the guy, who was driving, stop. That is when they found the issue (so I understand).
John
John,
I didn't get that from the original post,
QuoteSmoke started pouring out of the tag axle brake and we pulled over
but it doesn't really change anything.
You were lucky to have smelled the brakes burning before there was a fire.
The point is that when you buy a used bus, among the very first things on the agenda should be a complete and thorough axle service all around, regardless of what the PO might have said.
Brian may have thought that was what he was getting, but that was not the case.
The thing is that brake and axle service is so cheap compared to the safety value, it is not something to compromise on.
Len,
I know, what he told me on the phone didn't exactly match what he wrote. He said that it was dark, and it was only when they smelled the brakes, when they pulled over.
I do not know where the "smoke pouring out of the tag axle brake" came from. Maybe that was the assumption, or maybe they saw it after somebody else smelled it....who knows. If they didn't see if until somebody smelled it, I gotta wonder about the guy driving that bus. If it is dark, and you see the smoke (remember, they just went through downtown KC, plenty of light, or somebody else's headlights), then they should have seen the smoke before somebody else smelled it. When I drive, I am always checking my mirrors. Day or night.
John
Anyway he was in good hands I know both of those young guys Wade and Matt and they are well versed in brakes I can assure you of that and there is no sense in Brian having the repairs done on the road and spending a small fortune.
He just needs to watch and be sure the seal is not pouring grease one brake on a tag bad is not going to make that much difference in his stopping ability
good luck
Clifford,
I agree with you. But, I think Wade would have worked him in today, given that side a once over, and been set. He broke down less then 15 min from the Arrow shop in KC.
That is true, the tag isn't as big a deal as some of the others. They were still so close....
John
If he was that close John he should of let Wade look at but Brian is Brian what else is new lol
good luck
http://maps.google.com/maps?saddr=Exit+232A&daddr=Manchester+Trafficway&hl=en&sll=39.059392,-94.501272&sspn=0.007439,0.016512&geocode=FTrKUwIdjK5b-g%3BFSoCVAIdXAVe-g&vpsrc=0&mra=dme&mrsp=1&sz=17&t=h&z=17 (http://maps.google.com/maps?saddr=Exit+232A&daddr=Manchester+Trafficway&hl=en&sll=39.059392,-94.501272&sspn=0.007439,0.016512&geocode=FTrKUwIdjK5b-g%3BFSoCVAIdXAVe-g&vpsrc=0&mra=dme&mrsp=1&sz=17&t=h&z=17)
That close, Clifford....
I gave him the # and told him that's where I send or take my buses when we have issues in that area. I couldn't do any more over the phone.
;D BK ;D
BK,
I'm just curious. What do you do when you buy a used bus and before you put it in commercial service? And, how much do you expect to spend, over the purchase price before you put a used bus on the road?
I think that would be some valuable information for many folks here.
Quote from: Len Silva on September 01, 2011, 12:35:42 PM
BK,
I'm just curious. What do you do when you buy a used bus and before you put it in commercial service? And, how much do you expect to spend, over the purchase price before you put a used bus on the road?
I think that would be some valuable information for many folks here.
I am going to take a wild guess and say he checks the brakes :-*
Brakes were the big thing for me when I bought my bus, so the deal included a complete brake job, all corners. They did only an OK job, they left on a broken manual slack adjuster that the locking ring was broken on and the slack unadjusted itself in around a hundred miles. It cost $3000, and the left hand wheel nuts were put on at around 1,000 ft lbs of torque. It took a Snap-on 1" airgun at 140 PSI to get them off. If anyone wonders why I try really hard to do my own maintenance, that's a couple of reasons right there.
Buses in commercial service are different. They get full over the pit inspections every 30 days, with DOT paperwork on file. You do that before you put it in service, basically.
Brian
I'm not in commercial service but if I buy a bus or truck I run the codes or pay to have someone run the codes if I don't have the software. I do a complete undercarriage inspection including not only brakes but looking for leaks, evidence of parts rubbing or chafing, indications of work by non-professional mechanics (like wires or wire bundles just cut off and wires hanging), hub seal leaks, signs of recent and regular lubes, corrosion, and if equipped air bag condition.
When I drive it I look for temps and pressures in range, good even braking, good strong acceleration, and over heating when pulling long steep hills.
Nothing says junk like dry grease fittings, leaks, poorly adjusted brakes and a failure of the DOT brake test. A previous owner that presents long term log books documenting a strong preventive maintenance program gets a kiss on the lips. I love it when parts are replaced to a schedule and not when they break.
Len,
Great question!
Dad an I have been told by several sellers (and one has been in the used bus biz for yrs & yrs) that we go over and inspect a bus more thoroughly than anyone they've ever seen.
We load our ramps, jacks, tire/wheel tools creepers, tarps, card board, and many other tools and items we may or not need in the truck and spend a day or 2 going over any bus we are serious about buying.
Once we've gone over it dad starts negotiating price while I start load tools and equipment. Then I listen in on the negotiations and if I feel dad is being too stubborn and we're going to lose a great bus or a small amount of $ I jump in and get dad to the side and tell him I think he should go say an extra $1000. But if I feel dad is right on I speak up and tell him "I'm loaded and hungry, let's go eat and give him time to think about your offer!"
Most of the time we end up bringing the bus home if it's not junk! If it's apparent it's junk I don't even get serious on the inspection before telling dad it's not for us.
Now if it's a STEAL we have bought buses sight unseen on the condition it passes our inspection before handing over CASH $! (bought several off ebay this way!)
And we've walked or run away from many more than we've bought too!
But if a bus is selling cheap enough we'll buy it knowing we're gonna have to spend $10,000 +/- and anywhere from a month to a yr working on it as time/$ allows before we put it in service! (we feel if it's paid for free & clear when it comes home, it ain't eat'n noth'n while it sits waiting to be made road worthy!)
AND YES BRAKES, Wheel bearings and TIRES are the FIRST things we do to one if we have no knowledge of the history on it!
;D BK ;D
OK Brian,
I know you've taken some heat on this. But inquiring minds still want to know what it was and how you got back on the road!
;D BK ;D
after due consideration, post deleted
oops...
Some background on my bus and the work which has been done on the brakes and other parts:
I spent right about $9,000 at C&J Bus Repair having the brakes fixed from top to bottom in 2006. The shoes, drums, wheel bearings, and some other parts were replaced. I had them spare no expense in replacing what needed replacing. The bus has been taken to C&J Bus repair once a year since then and put up on the hoist to get everything greased and the brakes checked. I learned since then that the brake check they were doing is not as extensive as I thought I was getting. JD was surprised to hear we were having problems with the low number of miles since his guys replaced all of the brakes.
We stopped in Olathe, KS to get the brake problem looked at.
As I noted in another thread I am working to learn as much as I can about air brakes in the next days and weeks. I am going to order the Bendix training videos in the morning. I would go to the Bendix Air Brake School in Dallas next week if I had vacation time available.
Quote from: belfert on September 06, 2011, 04:51:12 PM\
We stopped in Olathe, KS to get the brake problem looked at.
I am relieved to hear that you did stop to get it looked at. What did they find, and who did you use?
John