Spring Brakes with ICC Brake Valve?

[luvrbus]

Are the ICC brakes just a service brake pod as we call it today ?,brakes are fairly easy to upgrade not a rocket science I have seen on old GM's the lever replaced the with a air parking brake 

I installed a hydraulic parking brake on the wife's S&S tied to the braking system push the pedal down flip a switch locks the drum on transmission and both axles brakes

[Dave5Cs]

Clifford, IYHO
So would it be a good idea to upgrade from DD3 to spring brakes on my MCI 5C and if so what am I look at parts and Labor aprox or just parts.

Dave5Cs

[artvonne]

4103s and 4104s came with only the mechanical drum parking brake. The result is that it is very tight fit to install spring brake chambers, but it is well worth the trouble. I don't think I could ever trust those drum parking brakes.

  Not recommended, don't try this at home...25 years ago and not as wise, I drove a GMC PD3751 home without air brakes, just the driveshaft hand brake. I could lock the rear axle if I hauled back on it hard enough and would leave rubber and smoke. It was a very powerful brake, one I wish this newer Bus had.

[buswarrior]

The colour of the knob matters not. The function of the valve it is screwed onto is of more concern.

This thread scares me in some respects.

If you own a bus conversion, you need to know how your brakes are supposed to work, and then check them to be sure they do. Or, be prepared to locate a reliable agent and purchase that service. Regularly.

This has to do with your responsibility to yourself, your family and the rest of us, the traveling public.

Please, proudly purchase current airbrake training materials, spend several evenings reading everything you can find from REPUTABLE SOURCES, not this or other internet BBS. What do you know? What do I know? Ignorance didn't stop either of us from typing words on here.

Bendix has an extensive library and lots of technical articles.

I am quite fond of "Practical Airbrakes" found here from the CVSA:  http://cvsa.stores.yahoo.net/pracairinhan.html

Strongly consider taking a proper air brake course at an educational establishment. A course for a technician would be even better than one for a driver, but both would be good.

For the MC5 question, it is a big job to swap spring brakes into an MCI, MCI took full advantage of the smaller size of the DD3 brake chamber in their suspension design. There is insufficient room to mount a spring brake chamber in the same place. Modifications involving heavy welding of new mounts is required, as well as hardware.

There is nothing wrong with a DD3 system, MCI was using it up into this millennium.

As for reliability, if a busnut changes out the inversion valve as part of their new bus preventive maintenance, give the chambers one pull of grease each, the chamber diaphragms are no worse at aging than those in a spring chamber, and may be changed out, unlike a spring chamber, which must be thrown away, and has a dangerous coiled spring contained inside.

Don't leave them lying around to maim the kids or the dog when they rust through.

happy coaching!
buswarrior

[RJ]

Amen, BW, Amen!

[Dave5Cs]

BW thank You for the info.

"if a busnut changes out the inversion valve as part of their new bus preventive maintenance"

Meaning a new or to rebuild one. Not to something else or newer correct?

Dave

[buswarrior]

Sorry, remove and replace the inversion valve with a fresh one.

Maybe $100 or so? For busnuts, I recommend just purchasing a ready to go valve. We lack the knowledge to make the crucial decision on whether a valve core is in suitable condition for rebuild or not. And the spread on the cost of the kit and a fresh valve isn't worth the time to most of us. No large fleet that I know rebuilds anything anymore, not worth the time, and the potential for error and having to redo it again.

The maintenance manual recommends changing the inversion valve on some periodic basis, which you can be absolutely sure that it hasn't been. Achilles heel, very few fleets change them, and the last commercial operator wouldn't even know that there was one...

It's function is critical to coach operation, as a DD3 system must be pressurized one way or the other to both park and to drive.

You control the inversion valve with the push/pull valve by the driver. The inversion valve switches where the parking air is directed, to the chamber parking portion to park, and to the chamber locking rollers to go for a drive.

When it has decayed sufficiently, and starts leaking, or refusing to fully switch between the two modes, you've got trouble that could have been avoided.

Mounted on the differential, a sawzall run vertically down the side of the valve body tight to the threads will quickly dispatch the large corroded nut that holds it on. Be sure to stop before you cut through the mount.

Also a great time to gather up all the hoses and have some fresh ones made up. If they are seized, easiest to label them, and just cut them to make removing the remains easier. And while you are there, and this far along, swap out the the rear service relay valve and the parking circuit regulator for new ones, and there's little left to worry about back there for a decade or more.

Use the anti-seize of your choice during assembly, everything with threads and mating surfaces, careful to keep it out of the inside of the airlines, but under the mating surfaces of the fittings, cuz you'll be very mad at yourself the next time...

happy coaching!
buswarrior

[luvrbus]

You guys not all spring brakes are a throw type or tamper resistance as they are called now that has just come into play in the last few years spring brakes are easy to service not like the DD-3 and the SD-3 

You cage the spring with the bolt that comes with those and the spring is not a problem replacing a $5 diaphragm compared to $100 diaphragm for the DD-3 or the SD-3 

If a spring brake canister has a V type band with a bolt like a service brake pod it is serviceable problem came when some nut twister releases the band before caging one and hurt himself.

To many moving parts in a DD-3 for a brake system IMO that is why Bendix sent those to the big house in the sky and refuses to support or supply parts for the DD-3 or SD-3 any longer long live the springs lol

good luck

[buswarrior]

You would re-use, or attempt to disassemble, a spring brake chamber typically found on one of the coaches that we busnuts end up with?

I am lacking in that courage now.

happy coaching!
buswarrior

[luvrbus]

Good point lol but I have seen some bad looking DD-3's come off these buses no way could you rebuild one

[buswarrior]

Yes, no matter which way a busnut goes, worn out, rusted up parts, assembled in unorthodox manners is the mainstay of the early years of troubleshooting.

happy coaching!
buswarrior

[gus]

Rick,

You owe no apologies. The 4104 brake system when modified with spring brakes and, like mine, keeps the ICC valve plus the yellow spring brake valve, can get very confusing. I never did figure out the plumbing on mine. Tried to remove the ICC valve and nothing worked! Gave up and left it!

It appears yours uses the ICC valve to set the spring brakes, a simpler system than mine and not as dangerous since pushing IN my ICC valve locks the brakes - really weird!!

On top of this the DD3 is another parking brake system altogether, but works fine, not as simple or trouble free as spring brakes though.

The original mechanical parking brake has nothing to do with any part of the air system. That whole system must weigh 300 lbs.

[bevans6]

Wow, what a thread!  I am away for a day and so much happens.  Hopefully it's now clear, but for the record DD3's are completely and totally different from spring brakes, the only similarity is they both are parking brakes, and they both work with a knob that the driver can push and pull.  One correction I did not see any one else catch - in many, if not all, installations they do not apply automatically when the service air pressure drops to 60 psi, or even zero.  That is because the  parking/emergency function is based on air provided by the independent, protected by check valves, parking/emergency brake tank.  Only when it gets down to the pressure dictated by the spring inside the push/pull valve - (20 - 45 psi per BW, I never bothered to test mine) - will the valve pop and the brake apply with the remaining pressure.  The way to test this is a two step process - first air up the bus, drain the wet tank then the dry tank to zero.  See if the valve has popped - if the check valves that protect the parking brake tank are working right the valve will not have popped because the parking tank will have full pressure in it.  Next drain the parking brake tank and the valve should pop when the pressure gets down.  If you want to know at what pressure the valve will pop at, just drain the entire system from the parking brake tank.  The pressure in the whole system will drop and the pressure gauge will follow the pressure down, so you can go look when the valve pops and see what the pressure is at.

One other note - brand new DD3's are available from REI.  I bought a pair and was quite happy with the quality, and the service was great.  I would go a long way to avoid replacing the brakes on an MCI like mine with spring brakes.  Clifford says he's going to, but I won't (and didn't) if there is a reasonable alternative.

Brian

[Oonrahnjay]

Print out the Air brake Handbook and study it thoroughly.  Just about everything you need to know is there.  Every bus nut should have this available.

http://www.wsafc.org/WSFMA/Shared%20Documents1/Bendix%20Air%20Brake%20Handbook.pdf

       That version is marked " (C) 2004.  I have two version on my harddrive marked 2008 and 2009.  I don't know where I got them (I'm guessing the Bendix site) but it would seem best to go with the latest issue.

[gus]

There is one really bad fault with mechanical drum parking brakes and with no air, if the U joint fails you have nothing!!

Even 25 years ago I wouldn't have had the guts to drive with only this brake!

I have a few antique heavy trucks with this setup and this part always worries me.