| Author | Message | ||
| Austin Scott Davis (Zimtok)
Registered Member Username: Zimtok Post Number: 340 Registered: 9-2006 Posted From: 216.37.73.226  Rating: N/A |
What type of brake chambers are these? REAR CHAMBERS http://i411.photobucket.com/albums/pp194/Zimtok/Buses%20Cars%20and%20Bikes/RearBrake-001.j pg http://i411.photobucket.com/albums/pp194/Zimtok/Buses%20Cars%20and%20Bikes/RearBrake-000.j pg FRONT CHAMBERS http://i411.photobucket.com/albums/pp194/Zimtok/Buses%20Cars%20and%20Bikes/FrontBrake-000. jpg http://i411.photobucket.com/albums/pp194/Zimtok/Buses%20Cars%20and%20Bikes/FrontBrake-001. jpg | ||
| Dallas (Dal300)
Registered Member Username: Dal300 Post Number: 213 Registered: 3-2006 Posted From: 75.88.242.228 Rating: N/A |
The front brakes are standard service air brakes and the rear look like MGM piggyback combination service/spring brakes. Check out this link. http://www.schoolbuspartsco.com/WebPages/brake/mgmshort.html (Message edited by Dal300 on June 30, 2009) | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1546 Registered: 10-2003 Posted From: 71.58.110.9  Rating: N/A |
You should be able to get replacements for these at any truck supply house. It should be a 30-30. They are made by three or four companies and are interchangeable. The new ones have crimped on rings. They are much cheaper than you would believe. They come with a long threaded actuator rod that you cut to the same size as the one on yours. You should check the overall length of yours, as the replacements vary in length up to approx an inch. I'm assuming you were going to replace one. If not, never mind.  | ||
| Randy Davidson (Rdavidson)
Registered Member Username: Rdavidson Post Number: 22 Registered: 7-2006 Posted From: 166.217.216.186 Rating: N/A |
Just today I had one of these replaced on the drive axil by Pocono Peterbilt. I could not hold air pressure in the primary system. Replaced my MGM with Bendix look-a-like at a cost of $97 (for the can) and 3 hours labor (rusty stuff) and misc stuff. Out the door for $426. I'm please because I could not have done this myself and I was in the shop watching the whole time. Much cutting and fitting. FYI, Randy | ||
| Austin Scott Davis (Zimtok)
Registered Member Username: Zimtok Post Number: 345 Registered: 9-2006 Posted From: 216.37.73.226 Rating: N/A |
I did want to know what kind they were and how easy they were to get parts for to rebuild/replace. It looks fairly straight forward as long as I can get the parts. I think one or more may have a diaphragm leak. When I apply the brake and hold it I can see the air pressure drop slowly and as long as I hold the brake the air will continue to slowly drop. I plan on getting under the bus and checking for air leaks while someone applies the brake. It could be the chambers or the air lines feeding them. Soapy water and some time will tell the tale.... . | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 375 Registered: 2-2001 Posted From: 69.77.157.8 Rating: N/A |
Austin, I use a piece of garden hose abour 5 feet long like a stethoscope to look for air leaks even before breaking out the soap spray. The hose won't find teeny ones, but the size leak you mention should be easy. It can locate where the air is leaking from on a particular component. Unfortunately, you still need someone to step on the brakes though I have had some success with sticks if they are the smarter ones! | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1548 Registered: 10-2003 Posted From: 71.58.110.9 Rating: N/A |
Don't forget that the safety brake portion has a powerful spring that you need to cage before dis assembly, so it doesn't take your head off when you remove the clamps. The diaphragms themselves are cheap and readily availability at any truck parts supply. Anti-seize the bolts on reassembly. Even if they aren't bad, you might as well do them anyway since you are under there. | ||
| Ralph Peters (Ralph7)
Registered Member Username: Ralph7 Post Number: 25 Registered: 3-2004 Posted From: 206.251.14.87 Rating: N/A |
If you change a pancake be certain to recheck for leaks at the clamp area of the new pancake, soapy water needed, leaks happen all the time. Most leaks, with regular (not DD3) are a diaphragms, worn hose, pin hole in hose, even a quick release valve may have dirt in it. Diaphram leaks normally start small. When foot peddle is applied it must be held steady, otherwise the qr valve will begin releasing air. |