help, i'm stuck in the driveway - park brake won't release.

[gumpy]

OK, I found it!  If anyone wants a copy of the DD3 seminar Ewen did at Bussin' 2006, I will email it to you. Although it would be much better with Ewen included, that is up to you.  It is in .pdf format and is 1.44 M.  You can PM or email me direct.  Jack

If you want to send it to me, Jack, I'll post it on my website and then put a link up here for anyone who would like to download it.

craig

[JackConrad]

Craig,
   It is on its way to you.  Jack

[pvcces]

Thanks, Jack and Craig.

Tom Caffrey

[Dallas]

Here's a PM I wrote to one of the other members.
I posted it here once, but it got lost out in the ozone of the Cyber Super Slab.

John was kind enough to send it back to me so I'll try again.

Hiya John,

It's possible that weak return springs can cause an otherwise functioning brake to freeze to the drum, however, in my experience, what usually happens is that when a driver comes in, his brakes are in a 'warm' state, which allows the moisture to stay on the drum and on the brake shoe.

Over 25 years ago, I learned that to stop the problem all that was required was to ride the brakes for 20 seconds or so before coming into the yard to park. this allowed the shoes and the drums to heat up enough to evaporate the moisture. This is a great trick to use when you are planning to leave again in a few hours or even a day.

For long term sitting, like when parked for the Christmas holiday, (or at a campground for an extended period), I was taught to keep the brakes released and stop the engine with the transmission in gear, chocking the wheels as needed of course. This allowed the shoes and the drums to come down to the ambient temperature and freeze solid before contacting each other. It's kind of like having frozen ice cubes together, as long as they are frozen, they won't stick to each other, but if you allow them to heat up to above freezing, they'll create a sheath of water which will cause them to become one piece.

The other cause of frozen brakes is the lack of air system maintenance. Even if you have an air dryer, it is a good idea generally to release the air from the wet tank at least once a day.

Most people don't even think about the air dryer as long as they cn hear it release. They seem to think that as long as it makes a noise, it's working. This is far from the truth. The desiccant cartridge needs to be replaced every year or 100,000 miles depending on use. Many times, even the company that owned the bus to begin with never changed the cartridge, even after 4-500,000 miles.

Just recently I replaced the air dryer on an Eagle 10 that was so far out of spec that it couldn't, even when new, keep up with the volume of air generated by the compressor. It originally had a Bendix AD-9 that at some point along the way had been swapped out for a Wabco medium truck version. This air dryer was meant for use in small dump trucks and delivery vehicles or car haulers using 1 ton trucks pulling 3 car trailers.

When we went to order a new cartridge, we found it was cheaper to swap over to a rebuilt Bendix AD-4 than to try and fix the other unit.

The AD-4 is a much larger unit than the Wabco and is even larger than the AD-9. I felt that with the inexperience of the owner/driver, the upgrade was worth it, since the recommendations for replacement and service on the AD-4 are at 300,000 miles instead of 100,000.

Hopefully, this will give the owner many years of trouble free use, since it will take him a couple of decades to drive that far and if he keeps his compressor in good condition, along with the air tanks drained, he should have fewer problems than he has in the past.

I think, since I typed all this while coughing, hacking and blowing my nose from a rotten cold, I'll go ahead and post it to the board instead of doing it all over again.

I hope this helped answer a few questions for you.

Have a great Christmas and a better New Year,

Dallas

[gumpy]

Craig,
   It is on its way to you.  Jack

Jack,

I didn't get this. Did it bounce?

craig

[JackConrad]

Craig,
   I just sent it again to your bcmagbb at gumpydog.com address  Jack

[gumpy]

OK. I got it, and it's loaded. The url is http://bus.gumpydog.com/miscellaneous/The_DD3_Safety_Actuator_Bussin_2006_presentation.pdf

[belfert]

I had an interesting experience this past spring when I thought my brakes were not releasing.  I couldn't get the bus to go after storing for months and assumed the brakes were stuck.

I went and got chocks and a hammer and tried to knock the shoes loose by crawling under the bus with the brakes released.  (I don't have air suspension.)  I tried moving again after that and no go.  Finally noticed in my mirror that the wheels were moving, but the bus wasn't going anywhere.  I looked over the situation and realized my wheels had sunk 4 to 6 inches into the gravel parking lot over the winter.  I was finally able to back up out of the holes I was in by carefully applying the throttle slowly.

The moral of the story is the problem is not always what you may think it is.  I'm not sure the brakes were ever actually stuck, but wouldn't be suprised if the pads rusted to the drums considering other rust issues I had after driving on Minnesota's salty roads to get the bus to the storage lot.

[cody]

Unfortunately, the inexperienced owner/driver that is refered to in this thread is me, with the air dryer problem, the much more experienced 'master' mechanic diagnosed the problem of my air throttle as a faulty air dryer and a lack of maintenance on it, the wabco unit refered to in the post was in fact a rockford unit and was correctly sized for the application and proved to be still fully operational, according to john at the napa store where the core was returned to, so several hundred dollars later and the next time the bus was used, the air throttle was again not functioning. I realize that mistakes can be made not only in the diagnoses of a problem, that is fully understandable.  Sometimes the easiest solution is over looked in the quest to complicate and teach a person bus mechanics.  A simple thing like a kinked air line can rob the throttle of the required air to operate as it should.  I fully understand how something like a pinched airline can be overlooked, especially when it is in plain sight, directly over the motor, mounted on the bulkhead, often the tree's can't be seen because the forest is blocking the view lol, but thats what makes life worth living. cody

[Gary '79 5C]

Cody,
Hey go easy on yourself, as I am right behind you on the learning curve here. Very enlightening for me as I have alot to learn on bus systems.
One thing I learned early on is that Experience is something you recieve just After you needed it. Tend not to forget that way.....

Merry Merry,

Gary

[Dallas]

Cody,

If you will recall, When we operated the air system, the Rockwell-Wabco air dryer did not purge as it was meant to.
Since there was no oil in the supply line from the compressor, and since there was water in the wet tank, the dryer was Not doing it's job, along with the fact that the heating element and thermostat weren't even hooked up.
You and I went to Napa together and looked for an AD-9 cartridge and overhaul kit. And yes, that was a mistake on my part, since the unit was actually a Wabco part, model 1200 if I recall correctly, even though the AD-9 was the original dryer installed in that bus, as evidenced by the mounting bolts.
With that particular model of Wabco air dryer, I stand behind my original statement that it was built for light applications, small dump trucks, 1 1/2 -2 ton 5th wheel puller car haulers and hotshots. It would even be serviceable for light semis and non air ride buses, if they were serviced monthly or on a known service schedule.
John at Napa told us that AD-9 parts would need to be shipped in at an added cost. We then looked for an alternative  and picked the AD-4 for your application. 1.) because service time could be extended. 2.) because it was less than $25 more than a rebuilt AD-9. 3.) the combined total to overhaul the existing air dryer was almost as much as purchasing one already rebuilt. 4.) It would be there the next morning at no added cost since it would come on the normal delivery truck.

The pinched air line to your air throttle I did point out to you before another technician decided to take over the job. It was suppose to be changed before you left.

It's very easy to second guess after the fact.

But then to use your phrase, you got exactly what you paid for.

Dallas

[cody]

The nice thing about this board is that we can disagree at times and still remain friends, after I had asked several times what I owed you for the work, you said for me to pay you what I wanted to pay, I offered you money ($400) and you wouldn't take it, you told me to keep my money, even tho it had not corrected the problem, I felt that you had done work over the course of several days and rightfully earned it, but I did enjoy meeting you and cat and wish you guys a happy holiday season and I'm sure we'll meet up again in our travels.

[Dallas]

It hadn't corrected the problem because the job was not finished.
However, you decided to stop in the middle and have another tech work on it, who obviously didn't fix it either, since it was stuck in Fl with the same problem.

DF

[Busted Knuckle]

Well to be totally honest here Dallas, another technician did not step in and take over! You'd asked me on Thursday as mom & dad left on their charter trip to look at Cody's starting problems and showed me the switches that you questioned which were which. At that time I told you I wasn't sure, that dad was the one who had lots of Eagle experience & was good with electrical systems and that we'd get him to help us with it when he came home Sunday. At that time you said ok, and I made the mistake assuming you were OK with that!  Well Sunday he didn't feel good and he did not touch it, of course niether did you! On monday around 2 PM dad started looking at it and found that a mouse had mad a comfy suite in the electrical panel box and chewed a wire into. Also the switches were old and corroded and stuck. so dad fixed the wire and changed the switches. Not once did you attempt to work on that bus on monday even after dad had asked if you wanted to back it in over the pit so you could do what you needed/wanted! Yes I admit I misunderstood you asking me about those switches and what I tought of Cody's starting problem as you asking for our help. Especially when you said OK to us getting dads help when he came home. If you were not ok with it you should have said so! But no you waited until after dad looked at it and started fixing it, to throw a temptantrum and walk off from finishing what YOU told Cody you wanted to do! I waited until late tuesday afternoon to back it in and change the oil as Cody wished to get done sometime this year, by whoever! Dad or I never intended to take over any of the job, but somebody needed to finish what Cody wished to be done and you made it obvious that you were done with it & US! I have no knowledge of the air dryer system's condition & like Cody agreed with you that if you said it needed replaced, it needed replaced!
I didn't know that John at Napa had told Cody that they discovered it was in working order when they cleaned it and tested it before returning it as a core, until just before Cody & Libby left when he told me so. So please don't go accusing me off taking over the job just because I stepped in and finished what needed done so Cody & Libby could make it to Jack & Paula's for Christmas as planned. I still like and respect you and Cat both very much, and wish the both of you good luck and great success in what ever you do! Again I did exactly what they say you do when you @$#~u~me something as I did on the starting system, but hey you are a grown man and could have said no I'll do it myself when I said we'd get dad to help us when he gets home! You were standing right next to me when I called mom & told her we wanted dad to help sunday when they got home!
  BK 

PS after receiving my whopping bill I'm surprised Cody & Libby could afford the fuel $ to make it the rest of the way!

[gumpy]

Gentlemen,

This is obviously a personal issue that you should be resolving amongst yourselves, not hashing and dragging each other through the public forum on Christmas Day.

Merry Christmas, and may Peace and Love be with each and every one of you. You're all my friends, though I've only met one of you. I do hope you'll take a few moments to consider the BIG PICTURE today.

Craig