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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: trey on August 28, 2007, 11:17:54 AM

Title: Are my breaks going out?
Post by: trey on August 28, 2007, 11:17:54 AM
My brakes started acting up a drive or two ago.. they still work i guess... kinda.. but you have to push the pedal all the way to the floor before they start breaking and when the bus finally starts to brake, it hits all at once, kinda slams'em on or something. Are my breaks going out? is it dangerous to keep driving my bus?

also... i dont know if this is connected to the brakes or not but when my bus slows down to stop, just before stopping, at that really low speed the bus kindof shutters.. I rolled to a stop to see if it still did it when i didnt use the brakes and it does. It didnt do it when i first got the bus.
thanks! ???
Title: Re: Are my breaks going out?
Post by: TomCat on August 28, 2007, 11:27:13 AM
If you have air brakes, they will need to be adjusted often to perform consistantly.

Jay
87 SaftLiner
Title: Re: Are my breaks going out?
Post by: FloridaCliff on August 28, 2007, 11:33:49 AM
Trey,

First thing I would do is adjust the brakes.

They have slack adjusters and must be checked regularly.

Have you ever adjusted your brakes?

Its not hard to do, but you MUST do it safely or squish to You.

Is your air pressure holding when your braking?

Yes, it is Dangerous to drive it with those brakes

Cliff
Title: Re: Are my breaks going out?
Post by: gus on August 28, 2007, 12:36:18 PM
Shuddering can be caused by not pushing in the clutch soon enough when you stop, or, if you have an AT, the torque converter can be causing it.

The driveshaft and U joints are another possibility but they usually don't show up except under power.
Title: Re: Are my breaks going out?
Post by: FloridaCliff on August 28, 2007, 01:46:01 PM
I sent this in response to an IM from Trey, wanted to post it here in case I missed something important.

Trey,

Do you have the maintenance manual for your coach?

Really helps to see the description and pictures.

Getting the rear up on ramps makes it a lot easier.

Chock wheels so it can't move, using wood, block up to body at lift points(In da books), I use 2X12's,  block up chassis stops so body can't come down, I use 4x4's's this is usually over axle, flat plat on top of axle.

This is EXTREMELY important to protect yourself if airbags should deflate.

Release parking brake

Slack adjusters look like a bolt head with a spring loaded side cover near the bottom of the drum towards the brake can.  You push in with a socket and then you can turn the bolt.

You should be able to see you pads turn in, you turn them until you feel resistance and then back off 1/4.

I have not tried this but have heard that you can tap on the brake drum and it will sound like a bell until you have it adjusted in, then back off until it rings again.

Cliff

Title: Re: Are my breaks going out?
Post by: Hi yo silver on August 28, 2007, 02:39:25 PM
Also, it seems to me that you can eliminate the possibility of the shuddering being from the automatic transmission by carefully shifting into neutral before allowing the bus to coast to a stop without applying the brakes. Ya better fix those brakes or you'll be trying to hit something cheap!

Dennis
Title: Re: Are my breaks going out?
Post by: TomC on August 28, 2007, 02:46:54 PM
First adjust the brakes- tighten down all the way then back off 1/4-1/2 turn-and make sure the coller is back up around the nut or else it will back off again.  Then look inside to see how much lining you have-should be at least 1/2".  Also check to see if any oil is leaking into the brakes.  DO NOT drive the bus again until you fix the brakes.  If you can't figure it out yourself, have it towed to a repair shop.  Good Luck, TomC
Title: Re: Are my breaks going out?
Post by: Don4107 on August 28, 2007, 02:50:30 PM
Always makes me nervous when someone asks this kind of brake question and gets a couple sentences or paragraphs on how to adjust brakes.  I think the only answer should be to have a professional inspect the entire brake system and repair as needed.  If the owner can get a true pro to teach him about adjusting and just as important inspecting brakes, great. 

"is it dangerous to keep driving my bus?"  Yes!

Trey, sounds to me like you may have some other problems and I would get it fixed before you drive it more.

Good luck. 

Title: Re: Are my breaks going out?
Post by: Sammy on August 28, 2007, 03:00:27 PM
Yes, it is dangerous to drive your bus.
Take it to a pro to have it repaired. Now is not the time to start learning.
Learn from the pro, as it is repaired - this time.
The brake system is a complex one, many valves, protection devices,etc, before the brakes actually touch the brake drum.
Please do not be offended by my post, I mean no disrespect.
I am a bus maintenance professional, over 25 years in the bus industry.
Brakes and Steering are the 2 most safety sensitive systems on the bus, or any vehicle.
You can get hurt,killed,or injure others.
My answer is only based on your original question.
Best of luck with your bus.
Sammy
Title: Re: Are my breaks going out?
Post by: buswarrior on August 28, 2007, 04:16:23 PM
Yup, me too. Don't drive anymore.

Get the pro to show you, buy books to learn.

You'll be ok!

Good for you to ask!

happy coaching!
buswarrior
Title: Re: Are my breaks going out?
Post by: TomC on August 28, 2007, 08:13:16 PM
ONCE AGAIN- DON'T DRIVE IT UNTIL THE BRAKE ISSUE IS RESOLVED!!! HAVE THE BUS TOWED TO THE REPAIR SHOP!!! Good Luck, TomC
Title: Re: Are my breaks going out?
Post by: gus on August 28, 2007, 09:45:09 PM
trey,

It just occured to me that since you are a newbie you may not have driven with air brakes before this.

If so please be advised that air brakes have a definite lag before they take effect.

What you have described fits exactly with pushing the brakes too far too fast and then when they do start working they are on with full air pressure, this will certainly cause some pretty impressive results.

This might have damaged the brake linings or warped the drums.

Try using the brakes gently at low speed to see if they work better.