Air brakes

[Gator48]

We are in our 3rd year of ownership and traveling in our 2006 Itasca Horizon. Retired last year and now have the time for the longer trips.

I always like to have a lot of stopping room so everything doesn't end up front because of a panic stop.
Last trip I had to make two rather short stops for brake lights and noticed if I feathered the brakes rather than hitting them hard I ran out of pedal at the end of the stop. In other words the pedal was hard on the floor with no travel left and the wheels were not feeling like there was anything left if I need to lock them up.

Will "pumping" air brakes give better braking or just use up air? With 36,000 miles I don't think the linings should be used up. I will probable get them checked, but I wondered what you all think.

input please.


Dave

[Ray_IN]

Gator48 wrote:
We are in our 3rd year of ownership and traveling in our 2006 Itasca Horizon. Retired last year and now have the time for the longer trips.

I always like to have a lot of stopping room so everything doesn't end up front because of a panic stop.
Last trip I had to make two rather short stops for brake lights and noticed if I feathered the brakes rather than hitting them hard I ran out of pedal at the end of the stop. In other words the pedal was hard on the floor with no travel left and the wheels were not feeling like there was anything left if I need to lock them up.

Will "pumping" air brakes give better braking or just use up air? With 36,000 miles I don't think the linings should be used up. I will probable get them checked, but I wondered what you all think.

input please.


Dave

I'll begin with asking, how long since you performed an air brake check? This should be performed every day of driving. The procedure is simple and only takes a few minutes. You'll find many online videos of how to perform an air brake check.
You are right, your automatic slack adjusters will not work with light pedal pressure. You must make several slow speed hard stops to activate them, as they only move one notch at a time.

[racecarfan]

Gator48 wrote:
Thanks for the input all.

I didn't get a chance to check for air leaks today. Yes I am very gentle on the brakes, mostly using the engine brake then light pedal pressure till stopped. My wife was a CDL examiner, and sometimes it's like being tested. LOL. I think I will also check the slack adjusters as maybe I AM too light on the pedal and they aren't adjusting themselves.

I am not against having the brakes looked at, but I would like to exhaust some things I can do before spending the $$$.


Dave

you actually have a engine brake ?

[Gator48]

Thanks for the input all.

I didn't get a chance to check for air leaks today. Yes I am very gentle on the brakes, mostly using the engine brake then light pedal pressure till stopped. My wife was a CDL examiner, and sometimes it's like being tested. LOL. I think I will also check the slack adjusters as maybe I AM too light on the pedal and they aren't adjusting themselves.

I am not against having the brakes looked at, but I would like to exhaust some things I can do before spending the $$$.


Dave

[racecarfan]

Terryallan wrote:

racecarfan wrote:

mabynack wrote:
Pumping air brakes is NOT recommended because every time you pump them you use up some of the air reserve. Pump them too many times and your brakes will lock up. You should apply them with smooth, steady pressure.

You should have your brakes checked if they aren't working correctly. They may need an adjustment or you may have a weak air line.

you would have to pump your air brakes many times in quick succession to deplete your air supply to the point of brakes locking up/
I have never personally read of or heard of this happening
I have thousands of miles driving air brakes and I will pump/stab mine lots of the time and find its quit effective

When I took my CDL test. I had to pump the brakes until the air was gone, and the buzzer came on. Was a test to see if the brakes were working properly. Didn't take all that long to do it really.

Driving down a hill and pumping the brakes is a ton different than sitting at idle and rapidly pumping brakes to make the low air pressure buzzer come on.we are not really talking the same conditions here at all

[Terryallan]

racecarfan wrote:

mabynack wrote:
Pumping air brakes is NOT recommended because every time you pump them you use up some of the air reserve. Pump them too many times and your brakes will lock up. You should apply them with smooth, steady pressure.

You should have your brakes checked if they aren't working correctly. They may need an adjustment or you may have a weak air line.

you would have to pump your air brakes many times in quick succession to deplete your air supply to the point of brakes locking up/
I have never personally read of or heard of this happening
I have thousands of miles driving air brakes and I will pump/stab mine lots of the time and find its quit effective

When I took my CDL test. I had to pump the brakes until the air was gone, and the buzzer came on. Was a test to see if the brakes were working properly. Didn't take all that long to do it really.

[FormerBoater]

Before you spend any $, take your coach to a large vacant parking lot. Put the coach in neutral with the engine running...fully stroke your brakes 10 times holding the brake pedal to the floor for 30 seconds each time.

Next, put the coach through some hard/panic type stops to remedy any brake glazing that may have occurred and to see if the step above put your automatic slack adjusters back in adjustment/calibration.

Based upon your narrative, you are very easy on the brakes (can cause glazing) and have not calibrated your slacks (should be done regularly).

Let us know if this helps.

[racecarfan]

mabynack wrote:
Pumping air brakes is NOT recommended because every time you pump them you use up some of the air reserve. Pump them too many times and your brakes will lock up. You should apply them with smooth, steady pressure.

You should have your brakes checked if they aren't working correctly. They may need an adjustment or you may have a weak air line.

you would have to pump your air brakes many times in quick succession to deplete your air supply to the point of brakes locking up/
I have never personally read of or heard of this happening
I have thousands of miles driving air brakes and I will pump/stab mine lots of the time and find its quit effective

[dave17352]

I checked the link above and it answered my question!

[mabynack]

Pumping air brakes is NOT recommended because every time you pump them you use up some of the air reserve. Pump them too many times and your brakes will lock up. You should apply them with smooth, steady pressure.

You should have your brakes checked if they aren't working correctly. They may need an adjustment or you may have a weak air line.

[ncrowley]

I was told to never pump air brakes. Just push down hard.

[Dennis_M_M]

Definitely have the system checked by a competent mechanic.

Good info on air brake systems here

and here

[FIRE_UP]

charlie good time wrote:
Air pressure RELEASES brakes.Brakes are applied by strong springs as air pressure is released.That is why you can not move until air pressure is adequate at start up.Slack adjusters might not be working correctly . In any case have them checked.

Charlie,
You are correct about the parking brake operation on air brake equipped coaches. However, he's not having difficulty in moving from a parked position, he's having troubles doing what appears to be a harder stop. The pedal on an air brake equipped coach should definitely not go to the floor, heck, on any coach for that matter.

If it were mine, I'd park in a parking lot some place, or at home, if you have a level spot and, build up air pressure, DO NOT APPLY THE PARKING BRAKE, have a partner apply the brakes hard while you maybe kneel down along side the coach at various points to see and or hear, if you can detect an air leak of some sort.

Our coach is very similar to yours . It's an '04 Itasca Horizon 36GD with the C-7 330HP CAT. It presently has 62,000 miles on the clock and, at present, it has around 90% still left on the brake shoes. Yours SHOULD be even better in what's remaining in brake shoes.

The fact that your pedal is traveling to the floor is not good and, fanning the brakes or pumping the pedal will not help. You've got an issue some place and it needs to be checked out pronto. Good luck.
Scott

[charlie_good_ti]

Air pressure RELEASES brakes.Brakes are applied by strong springs as air pressure is released.That is why you can not move until air pressure is adequate at start up.Slack adjusters might not be working correctly . In any case have them checked.

[lanerd]

Yep...air leak for sure. Never, never pump air brakes.

Ron

[Sully2]

Terryallan wrote:
honestly. It sounds like you have a air leak.

...sure sounds that way!