I'd like to get under the bus and adjust the slack adjusters (assuming they're manual because I've yet to get under there and verify) on the drive and tag axles. In the maintenance manual (see attached) it says to do it with the wheels jacked up. I was thinking of building ramps to drive onto so I could get under the bus and grease zerks and check the differential fluid while I'm down there. Do I need to have the wheels off the ground to adjust the brakes? It would be nice to be able to spin the wheel and listen for dragging shoes.
I understand the process for brake adjustments. I also understand the need for safety when getting under the bus.
Use your ramps for the maint. work and just use a bottle jack to lift one wheel at a time to adjust the slacks.>>>Dan
I asked the same question last season. Here's the thread: https://www.busconversionmagazine.com/forum/index.php?topic=33278.msg379101#msg379101
Quote from: richard5933 on April 20, 2019, 06:12:58 PM
I asked the same question last season. Here's the thread: https://www.busconversionmagazine.com/forum/index.php?topic=33278.msg379101#msg379101
Perfect. Thanks!
You want to know what you are starting with for brake stroke, and whether they need any adjustment.
If they are auto slacks, they are broken, if they need adjustment.
If they are autos, each model has different procedures for install and set-up. There are some that will be broken by throwing a wrench on them the wrong way.
Measure the stroke before and measure it after, and then as times go by, you will have a clear idea as to whether it's time or not.
And a newbie catches themselves backing it off instead of tightening it up...
"Traditional methods" skip measuring, and then you know nothing of what you had, and whether you were wasting your time, or were in grave danger and should be doing it sooner.
Happy coaching!
Buswarrior
You guys should read all the BS the FMCSA CFR 396 has come up with in 2017 for working on air brakes, for years people have done their own brake work now you need certification to even adjust your brakes on your vehicle lol has to be a attorney involved some where
Quote from: luvrbus on April 20, 2019, 09:08:27 PM
You guys should read all the BS the FMCSA CFR 396 has come up with in 2017 for working on air brakes, for years people have done their own brake work now you need certification to even adjust your brakes on your vehicle lol has to be a attorney involved some where
Sounds like this is for vehicles in commercial service only, and from my reading of the quoted regs it's still possible for carrier to self-certify one of their own mechanics to do the inspections/adjustments if he/she has the requisite experience (one year) doing such inspections/adjustments.
We can't continually point out how bad today's drivers and mechanics are in one breath, and then complain about mandatory training on brake adjustment?
Ontario took care of this 20 years ago. Apprentice training fixed, driver certification to touch 'em. And modernized the airbrake endorsement for licences, that needed some work, since inception circa 1988.
The depth of ignorance amongst established mechanics and drivers was epic, once they got into it. And where do we send newbie's to learn?
Brake "failure" in days gone by? Perhaps self inflicted suicide by the driver using the wrench wrong?
Can you imagine today's drivers running without auto-slacks? Trucks would be burned to the ground from brake fires, or ramming into things, and flying off the sides of mountains at a staggering rate.
Auto slacks have been mandated since around 1995 on new equipment.
Buses have been optioned with them since at least 1975, my MC8 came with them.
Mandatory brake knowledge isn't going to hurt anyone as much as not knowing will.
Happy coaching!
Buswarrior
Try and find a place to get the certification to adjust brakes in Ontario. I phoned everywhere and nobody will do it unless you have a full class. They said to make sure they are okay before you go out and as they don't go out of adjustment that fast don't worry about it. The one place that did it hasn't done a brake course in many years.
Gnarly, I have a "80" 5C. It has auto adjusters on the rear and manual on the front. So yours maybe set up the same.
There is zero demand for the manual adjustment course now. Everything is auto slacks, and no fleet, large or small, wants their driver's touching the brakes anymore here. In fact, the way it is written, only a mechanic can mess with auto-slacks, because if they need messed with, they are broken and need the mechanic.
Once a fleet got their brake ignorance sorted out, they retrofitted auto-slacks, took proper care of them, and never looked back.
The authorities don't care about the vintage equipment crowd, and we don't want them to start!!!
The brake adjustment course is based in the Colleges and Universities Ministry, along with all the apprentice training. You get the same licence paper as the rest of the trades, with the appropriate designation on it.
The MTO/DOT takes care of the driver licence air brake endorsement part.
Perhaps joining the appropriate apprentice module at the College as it is being delivered to them?
It's been a long time, I'll see if anyone remembers me, let's see if there's a busnut and vintage truck owner solution.
Happy coaching!
Buswarrior
Quote from: Bill Gerrie on April 21, 2019, 05:19:21 AM
Try and find a place to get the certification to adjust brakes in Ontario. I phoned everywhere and nobody will do it unless you have a full class. They said to make sure they are okay before you go out and as they don't go out of adjustment that fast don't worry about it. The one place that did it hasn't done a brake course in many years.
Quote from: richard5933 on April 21, 2019, 01:12:19 AM
Sounds like this is for vehicles in commercial service only, and from my reading of the quoted regs it's still possible for carrier to self-certify one of their own mechanics to do the inspections/adjustments if he/she has the requisite experience (one year) doing such inspections/adjustments.
It wouldn't hurt a bus owner to have a little training either,some of the sh** I see and read on boards you just shake your head
My MC-5C has manual on the front and auto on the rear. I check the throw any time i have the rear wheels off, and by cranking the steers out so I can reach the slack - easy on my bus. In Nova Scotia I have a DOT inspection once a year, and he checks the throw as well. I have to say that having only put 15K miles on since a full brake job, they haven't needed adjusting yet... I have no idea if the rear auto-slacks work, but the throw never changes.
Quote from: luvrbus on April 21, 2019, 07:07:50 AM
It wouldn't hurt a bus owner to have a little training either,some of the sh** I see and read on boards you just shake your head
Agree.
One of the things I like about the shop where I take my bus for much of the service is that they allow me to spend time watching and asking questions. Even though they're doing the work, I want to understand as much as possible why they're doing it and how it's supposed to be done. I've probably added a few hours onto the bill for my larger jobs, but it's worth it to me to learn what makes my bus tick.
You don't need to jack up the wheels off the ground. First make sure there is enough space underneath for you to crawl if the air bags deflate-so not to crush you. I first grease everything. On my Transit that includes zirks in the brake drum on the brake shoe rollers. Take your 9/16" wrench, push down the locking ring on the slack adjuster, then turn tighten the brake until it stops-not necessary to tightly do this. Then simply back off 1/3 of a turn and you're done! Good Luck, TomC
Agree with Tom C. My 5C though has manuals on both front and rear. To do the rears I have to be up on my ramps to get to them or take off back tires.
Old school guys would insert a business card tighten till you could not pull the card out, back off till the card came out easy lol that is high tech stuff there
Auto slacks and auto drains....
There are at least 11 other things one should be looking at while under the rig.
Never been there and you'll never know.
I would not have auto slacks.
Auto slacks doesn't mean you ignore them.
On the same interval that you feel the need to adjust, you measure the stroke, or look at your installed stroke indicators to confirm they are in adjustment.
With this hobby going the same way as the professional drivers, might be a good idea for 'em all to have auto slacks? Nothing getting checked anyway...?
I am no fan of auto drains either...
Happy coaching!
Buswarrior
What is involved in installing stroke indicators.
After my recent air dryer purge valve experience, I've been studying the air and brake system of my bus. I have a way better understanding of the brake system now.
I actually think it wouldn't be a bad idea to make people get air brake certified to drive one (even for personal use). Kinda freaks me out how little I understood before! If you don't know much about your air brake system and how it functions, go on YouTube. There are lots of great videos.
When I bought the bus almost 5 years ago the guy showed me how to add diesel, how to start the engine and how to open the door.
"Ok, need anything else?!" he says to me.
"uhhh... Yah. How do I drive it?!"
After my brief lesson where I learned not to tap the brakes constantly when making a 10 point turn out of his compound, we were on our way and bus life had begun.
After stopping at a Walmart in Oklahoma to get sweatpants to put over our jeans as winter greeted us on our way back to Minnesota, the bus wouldn't start! I started getting worried and frustrated. I hit the switch to start it up in the rear and nothing! The two switches up front were on so why wasn't the engine turning over?!
My wife walked away and asked a trucker if he knew why our bus wouldn't start. "uh, is it in neutral?". My eyes got real wide and I knew instantly he had nailed it.
I walked back to the bus and put it into neutral then it fired right up.
My point in this story is just that this has been a learning experience from me for years now. I started from knowing nothing and without a teacher. I've learned some good stuff on this forum and YouTube.
The more I've learned the more I take safety very seriously. Many systems on the bus need to be inspected and maintained regularly. This is especially true of the brakes. I don't have much extra money and I prefer doing things myself so here I am. Good mechanics are hard to find and no one cares more about my bus than me.
Thanks to all the knowledgeable people who post on this forum. I appreciate it. I don't know a ton so I can't always post on other people's threads and I have a slow time accessing the site without Tapatalk but I try to make up for less knowledge with adding more photos of my little projects for the people who come after me!
Brake stroke indicators can be as simple as attaching a zip tie to the pushrod against the face of the chamber and observing the distance it stands off when brakes applied, attached goal posts with a pointer pin replacing the clevis pin for rubber boot equipped pushrods, all the way to an in-cab indicator that shows in the moment stroke.
That one is neat, you'll see a slight lngthening of the stroke if you put some serious heat to the drums.
Google "brake stroke indicators" and click on images to see a forest of them.
Spectraproducts.ca is where Big Transit here got theirs for their extensive support truck fleet.
Happy coaching!
Buswarrior
Quote from: Fred Mc on April 21, 2019, 07:45:05 PM
What is involved in installing stroke indicators.
Put a tie wrap around the push rod at the face of the chamber with the brakes off, apply the brakes (parking brake is fine for the rears, stick on the pedal for the fronts), measure how far the tie wrap is from the front of the chamber. Chock at least two tires front and rear if you crawl under to look at the rears. When I took my air brake course it was pointed out that if I was ever stopped by DOT for a roadside check (quite common in certain places and times in Ontario) I would be in some trouble if I didn't have a push stick for the pedal because checking the brake stroke is part of the mandatory daily inspection on trucks (less so on buses, which in Ontario get mandatory inspections every month/10,000 KM, from memory). I bought a brake pedal push stick (hook for around the steering wheel, adjustable length, I use it to hold the door open mostly) at my local truck parts store.
LOL there is a lot more to a air brake system than adjusting the brakes ,someone told me Bendix had a on-line course now it's probably cheaper than 400 bucks for the hands on course and cold sandwich some Utube stuff I ?
I took the air brake coarse ( weekend coarse cost $ 350 and inc. the licence ) and this is the type of clamp I use . you reverse the end of the clamp so it push's the brake peddle and the other end push's under the steering wheel . I think mine is 30 " long . it works great for other things and as of yet have never been asked to use it when on the road
https://www.amazon.com/dp/B07K9ZV8MZ/ref=sspa_dk_detail_2?pd_rd_i=B01H63VLPG&pd_rd_w=qO5yE&pf_rd_p=8a8f3917-7900-4ce8-ad90-adf0d53c0985&pd_rd_wg=5oWn9&pf_rd_r=7T73EH1M2HBRMW9M30S8&pd_rd_r=efd9594b-6518-11e9-9f49-5707d913d0fd&th=1
dave
Thanks for the pic. I probably have a couple of those.
Jim
Don't mind the water... we're under flood conditions...
Here's the zip ties used on a truck. With brakes released, the zip tie would be against the chamber, so a quick glance, and all is fine.
Happy coaching!
Buswarrior
Update:
Pasted from my thread on greasing in case someone needs it here in the future:
We got the jacks, ramps and stands out to grease up the rear end of the bus yesterday. This was our first time lifting the back of the bus up and it went very well. I flipped the dash switch to drain the tag axle air then flipped the valves in the engine compartment to finish draining the tag airbags. Then I backed over two 2x12s and chained up the tag axles. I don't think the chains I've put together were the right size (none came with the bus) as they weren't tight when the bus was up.
We ran up on 2x12 treated ramps. Those were made from an 8' on each side. We normally a board of two for leveling when we're parked. Then we used two 20-ton HF air jacks to lift the bus using the jacking points. We placed the jacks on 12"x12" squares of 1/4" steel channel we'd painted blue with tractor paint to keep them from rusting. (they have 1" lips on two sides and are often used for stair tread in industrial applications but we found them in the steel yard scrap bin. These steel squares were on top of 16x24ish 3/4" plywood to help spread the weight because we were on asphalt. Once we got it up high enough we let the axle down on the ramps and the body rested on the 22-ton jack stands (I love those things). We kept most of the axle weight on the jacks. So we had a some redundancy in case one should fail.
Adjusting the Drive Axle Brakes:
We adjusted the rear brakes yesterday. After greasing the rear end, we double checked the front wheel chocks and got to work. The wheel chocks are absolutely necessary because you need to release the parking brakes to adjust them. I found out I have manual slack adjusters on steer, drive and tag axles. I expected to find autos on the drive but nope.
We lifted the axle off the ramps and started by measuring the brake chamber stroke lengths. The DD3 chambers were adjusted first. The lock sleeve that needs to be pushed down to adjust the slacks were all stuck but freed up easy with a lil' PB Blaster, a wrench and a some light hammering. The drive axle slack adjusters we kind of a pain to reach as the bus wasn't high enough to sit up under it so I had to do some gymnastics to reach them. I tightened them down tight and then backs off 3 notches (per the manual) aka 1/2 turn. I did it multiple times to "practice" and make sure I did it correctly. Then I measured the stroke length. They were good. The angle formed by the slack adjusters and chamber push rods were all over 90 degs when applied which is what you want. I tested my work by spinning the wheels and having my wife hit the brakes (this job is a lot easier with a partner).
Adjusting the Tag Axle Brakes:
Compared to the drive axle, the tags and front axle are super easy to access. When I got to adjusting the tag axle slacks, I noticed an obvious air leak out of the passenger side brake chamber when the brakes are applied. I sprayed lots of soapy water then realized it was coming out of a hole on the side of the chamber. From what I've read this is likely to be a leaking diaphragm. The brakes still applied forcefully. I ordered new diaphragms for both sides. I might just replace the chamber as they are super cheap.
We're gonna do the steer axle brakes today.
Nice post. I'm needing to do the same soon and just got some inspiration. Like the safety consciousness and measures to make the repair goes as safely as possible.
When you test the brakes, you do this without air I assume? Doesn't seem right to have to run the bus or get the air tanks full but maybe so.
Glad I could be an inspiration!
The bus does need to be aired up to adjust the brakes. I used a few alt 200 psi, 5 cfm @ 90 psi compressor which works pretty well. See attached photo. I believe it should be kept at above 100 psi. This is so the parking brakes release ( don't forget to chock the front tires!) and so that when you press the brake pedal the brakes activate. It is possible to adjust them by pulling the brake chamber push rod out with a pry screwdriver and measure, but it doesnt seem to be as accurate. The pulling force you can make manually doesn't come close to the pushing force the brake chamber would make. People do it both ways, though.
Hope that helps!
Oh man! We had our first drive today after doing the brakes. What a difference! I'm gonna be honest with everyone and tell you that I should've done this probably a couple thousand miles ago based on everything I know now. I was beginning to have to compensate for the weaker brakes by using my jakes and downshifting. Don't be like me.
I'll adjust them once a year now which is about 2500 miles for us. It's a good time to check for leaks and proper function of the brake systems.
I'll feel much more confident driving through Vegas this fall!
Quote from: GnarlyBus on June 27, 2019, 01:00:22 PM
Oh man! We had our first drive today after doing the brakes. What a difference! I'm gonna be honest with everyone and tell you that I should've done this probably a couple thousand miles ago based on everything I know now. I was beginning to have to compensate for the weaker brakes by using my jakes and downshifting. Don't be like me.
I'll adjust them once a year now which is about 2500 miles for us. It's a good time to check for leaks and proper function of the brake systems.
I'll feel much more confident driving through Vegas this fall!
People don't use brakes in Vegas do they ?
Ha, no the brakes are for when they dip in front of me to make the last minute off ramp! And I'm in the second lane!