Hissing brake chamber

I have put new 3030 brake chambers on & a week later both had very, very small leaks. took about 20 min for the soap to bubble in tiny bubbles. even NEW is not what it used to be.

 

Daiphrams go out a lot. It happens and it's normal. I had 3 of them replaced in a matter of a month. Finally got sick of it and and put a new brake chamber on. Seems like it happens a lot more often in the winter. I've got a list for what's going to get done to my truck within the next couple months before winter hits and 6 new brake chambers are on the list. For the cost of putting a diaphram in the chamber I can buy a new chamber and put it on myself. I don't care to start ripping brake cans apart personally. And by the time it goes to the shop and I get charged parts plus an hour labor I can put a new chamber on myself.

Good catch watch those gauges constantly and listen. You can always tell when you're leaking air by listening to the compressor cut out going down the road and how long it takes you to build your air pressure. I build air every 15 miles usually thanks to a ride height control valve issue on my tractor. If I can't make it that far before it builds air and it takes more than 20 seconds to build air at highway speed my rig gets pulled over at the closes safe place to stop and I start walking around and looking for an issue. Know your truck and be aware. Also take into account what KWcujan said. Keep your foot off that brake pedal with the air valves pulled. I watched a guy pull the johnny bar down to check his tail lights with the emergency pulled...and then heard a few cuss words I didn't know existed. 2 diaphrams and 2 hours labor later he was back on the road...lesson learned.

 

Good point 379exhd. I skipped including the johnson bar, when your red/yellow knobs are pulled out.
That has the identical effect as the brake pedal being applied, except it will "only" damage the trailer's chambers.
I say "only" like it's something cheap and easy to fix. lol

 

You could always pull the red button (supply line popout button).

 

It's all good. Damaging a trailer isn't as bad as a tractor IMO. Yes it's still bad but trailer brake chambers are pretty easy to replace as opposed to a tractor chamber. Although you have 4 chambers to replace on a trailer and usually on 2 on a tractor. But it's easier for me to replace chambers on the trailer being spread axle. That brings me to my next point of why we as drivers should always carry vice grips. When you have a diaphram leaking you can always push in the air valve cage the spring brake and then pinch off the air line. Yea it leaves you with 9 brakes instead of 10 but it eliminates the air loss through the diaphram and stops the air leak. What's more dangerous driving down the road with a bad brake can or only 9 brakes? I don't know for sure I've driven on 9 brakes and with an air leak personally I'll pinch off the line from now on. It's not that bad getting it stopped but I'll be ###### if I'm going to risk having that emergency pop going down the road.

 

True, but at that moment I was too busy watching traffic & amazed at how fast it was dumping all my air.
As I was pressing harder & harder on the brake pedal, I watched my air pressure plummet to nothing, within seconds.
My spring brakes worked very poorly, at best. Brake adjustment was good, but the cans were old and I believe had significantly weakened springs.
That sound feasible?
Not sure if setting the spring brakes any earlier would have helped much, in this case. They didn't even lockup the wheels or work well, at slow speed.

 

I understand it happens real fast, but next time you will be ready. By shutting down the air supply quickly to the trailer, it saves your air for the tractor brakes.

Also if on a steep hill stab braking works best in this situation, stab until you can shift to lower gear then stab easily to allow compressor to build up pressure.

Same thing happened to me on a long icy hill in the middle of the night. Only by analyzing what I could have done better after the incident was I prepared if it ever happens again.

 

http://www.youtube.com/watch?v=LmrP_BxMfOI


Ever heard of a an anti compounding valve, it prevents overload from pushing brake pedal with spring brakes applied, all trucks should have one!

 

Bingo, it just hit me (thanks to your post).
Being that my service line came loose, I had been thinking pulling my trailer supply would only dump my emergency (trailer) air and only activate my trailer spring brakes, but had completely overlooked that pulling my supply (red) valve would ALSO be shutting off air for the "open" service line to the trailer. Duh, on me!
I did a "modified" stab, lol, in that it began as a normal brake application but within a second I was pressing hard to the floor. Seemed like the air was going out... way faster than the pressure to the pedal was increasing. I was watching the gauges during most of it, as well as traffic ahead.
Granted a true stab, quick and hard, would have been best, under these circumstances.
That's whats great about TTR. Always learn something new, even if you knew it before at one time! lol
Thanks Crossroads!

THAT'S the protection valve that CondoCruiser had mentioned! Great informative video. Thanks for posting.
I never knew they had a newer safety valve to prevent pressure overload from applying brakes while you have your spring brakes on.