| Author | Message | ||
| Jim Rink (Fakeguy)
Registered Member Username: Fakeguy Post Number: 122 Registered: 1-2005 Posted From: 70.61.17.72  Rating: |
I still have the original brake system on my '62 4106 (air applies brakes...no air, no brakes and will roll freely). I want to convert to MAXI's....looking for how-to and part resources. All help appreciated. Thank you in advance | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 295 Registered: 3-2007 Posted From: 71.55.199.152 Rating: N/A |
Jim; I had an 06 and had a problem and I like you said I'll just put on maxi's. NOT. They wouldn't fit without $$$$$. so drawing board here I come. Found out the dd3 chambers needed to be rebuilt and that solved ALL my problems. Now there maybe available replacements for them now but then NOT! Maybe someone will be able to assist you further in this matter. gomer | ||
| Jim Rink (Fakeguy)
Registered Member Username: Fakeguy Post Number: 123 Registered: 1-2005 Posted From: 70.61.17.72 Rating: N/A |
Marvin...not sure what you mean. I do not think I have DD3...Mine are original where air applies brakes not holds them off like maxi's. It takes air to have any brakes at all unlike maxi's that uses air to release brakes...or may I am just confused. Not sure what DD3 brakes are...either way, thank you for the reply | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 514 Registered: 10-2006 Posted From: 151.199.126.23  Rating: N/A |
I believe the rear mounting bracket will have to be moved. I don’t think it is all that expensive and absolutely worth every penny. I can try to take photos of mine when I have the wheels off but that might be awhile. If I locate any photos on the web I will post a link. | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 515 Registered: 10-2006 Posted From: 151.199.126.23 Rating: N/A |
Special note: This photo is not of my bus, I only wish it was. GM4106 spring brake conversion:  http://webpages.charter.net/schula/bus9.htm Taken from: http://webpages.charter.net/schula/index.htm | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1224 Registered: 5-2001 Posted From: 65.74.65.209 Rating: |
Jim, there have been quite a few people who thought it was worth going to spring brakes, like you want. Since they were not an option for original equipment, some modifications are needed that increase your liability if a failure in your installation plays any role in an accident. We were faced with the same choice around 8 years ago, and we considered DD3, but I coudn't stand the price those chambers brought. I inquired about fitting spring brakes on ours and got a shop to modify the brackets that the cans bolt to. These have to be shortened about 2 inches to accept the spring pots. Since the brake on a wheel end will fail if one of these mounts should break, they have to be very strong. With the shorter brackets, there should be about 1/2" of room between the pot and the bulkhead when installed. Do not cut a hole in the bulkhead to make room for these cans. I have seen a bus that had this done and the bay floor wrinkled and cracked from the loss of support. Be sure that the air for the parking brake valve comes from the brake side of the system, not the auxiliary. Your air gauge should be on the auxiliary side. We have never regretted going to spring brakes, and I could not accept the stock equipment with Johnson bar and ICC valve. If you should be going down a long mountain grade at a pretty good clip and blow the diaphragm on either rear pot, you would lose both the service brakes and the ICC circuit. The Johnson bar by itself would be inadequate, in my opinion. The stock pot has one hose, the spring brake has two hoses and the DD3 has three hoses. That should end any confusion about which equipment you have. For what it's worth and YMMV. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 479 Registered: 10-2006 Posted From: 208.100.193.170 Rating: |
"and I could not accept the stock equipment with Johnson bar and ICC valve. If you should be going down a long mountain grade at a pretty good clip and blow the diaphragm on either rear pot, you would lose both the service brakes and the ICC circuit. The Johnson bar by itself would be inadequate, in my opinion." Well I guess the size of the hill is the key here. I have sucessfully slowed (at a reasonable rate as most traffic does) with ONLY the Johnson bar as an experiment on the interstate. It will bring the bus to a normal stop should the ICC system fail at the same time as the regular breaks.Might not on the Grapevine tho. I prefer the stock system as with a failure the coach can still be owner moved , not require the wait for the hook. I have read of folks that lost the air compressor , ran the noisemaker and a small air compressor and were able to run home (a few days travel) to repair. Different strokes, FF | ||
| Kyle Brandt (Kyle4501)
Registered Member Username: Kyle4501 Post Number: 450 Registered: 9-2004 Posted From: 65.23.106.193 Rating: N/A |
When installing the spring brakes, make sure you have room to install the "cage" bolt. (It retracts the spring mechanically, no air needed.) Otherwise, towing it may prove interesting.  | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 516 Registered: 10-2006 Posted From: 151.199.126.23 Rating: N/A |
At normal ride height there is very little to no room to access the cage bolt on a 4106 that has been modified to spring brakes. The reason one needs access to the cage bolt is that it allows you to back off the spring so you can move the bus or work on the brake chamber (There are other ways around that, but it requires a lot more work, time, etc.) Depending on what type of leveling system you have, you can raise the bus a few inches to obtain access to the cage bolt. Without a leveling system, disconnect the leveling valve rod and manually adjust it to accomplish the same result, you only need a few inches. For those reading this that might not be familiar with air ride buses, it is absolutely life or death critical, that you properly block your bus up while you are under it. Also, do not work on the brake can unless you have educated yourself on the dos and don’ts. That spring can make them as dangerous as a cocked pistol if not handled correctly; it can maim and kill also. | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 296 Registered: 3-2007 Posted From: 71.55.199.152 Rating: N/A |
Barn Owl; Is that a new 4106 or what? I ain't seen one that clean since I went on a tour of a conversion company in Indiana. Wow that is cool and I do like the set up. When I had mine they didn't make anything that would work SAFELY and I would not take a chance. Gomer | ||
| John and Barb Tesser (Bigrigger)
Registered Member Username: Bigrigger Post Number: 103 Registered: 9-2007 Posted From: 24.179.147.233  Rating: N/A |
If your going to upgrade, I would suggest going all the way to modern maxi brakes and not DD3's. I can get a replacement maxi can for my truck for $50-75 and just the two diaphrams for these DD3's cost me $183! | ||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 24 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
All trucks and buses now have Maxi brakes-where air pressure is used to release the brakes and no air will apply them. If you haven't experimented to see how well they work, do it in a parking lot. Get up to 20mph and apply the brakes. Should be a sharp braking effort. To install maxis on a non maxi bus, you just need an air supply to the yellow pull valve, air line back to the rear axle, a T to the two cans. No air relays needed-simple install-but very effective. Good Luck, TomC | ||
| Jim & Linda Callaghan (Jimc)
Registered Member Username: Jimc Post Number: 55 Registered: 2-2004 Posted From: 66.175.206.159 Rating: N/A |
Marvin, I think that picture came from Al Schultz's (Southern Wis) bus, he did the work himself, and the rest of it is that clean also, check out the link by the pictures. Jim | ||
| Jim Rink (Fakeguy)
Registered Member Username: Fakeguy Post Number: 124 Registered: 1-2005 Posted From: 70.61.17.72 Rating: N/A |
WOW...thanks for all the replies. I am reconsidering my decision based on all the input, but now with lots of info Thank you to all | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 517 Registered: 10-2006 Posted From: 151.199.126.23 Rating: N/A |
Gomer, I can honestly say I have never seen a GM that clean. I truly don't know how people do it. Laryn | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 518 Registered: 10-2006 Posted From: 151.199.126.23 Rating: N/A |
I need to mention that just because you convert to spring brakes doesn’t mean you need to remove the manual parking brake although most people do. The PO of my bus left it in and it still works. Here in the mountains I take my bus places most people wouldn’t, and I wouldn’t want to depend totally on just a manual parking brake. That might just be my own paranoia but so be it. | ||
| Jim Rink (Fakeguy)
Registered Member Username: Fakeguy Post Number: 125 Registered: 1-2005 Posted From: 192.88.212.44 Rating: N/A |
Barn Owl: what's a PO? | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 572 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Previous Owner | ||
| marvin pack (Gomer)
Registered Member Username: Gomer Post Number: 298 Registered: 3-2007 Posted From: 71.55.193.233 Rating: N/A |
I checked out the pictures of the coach and that is awsome. Was he totalled retired? I barely have time to work on mine let alone wash it LOL If you haven't seen the pics GO DO IT NOW!!!! You will be ashamed of yourself after that. Gomer | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 737 Registered: 11-2005 Posted From: 208.54.200.110 Rating: N/A |
Jim, As I remember the brake pots come in two sizes and the smaller ones have to be used on a 4104 so I assume the 06 needss the same size. Barn Owl, My guess is that the spring maxi wheel brakes are about four times as effective as the original hand one brake drum on the drive shaft. There is almost no way both spring brakes can fail at the same time unless they are grossly out of adjustment. I have a few antique trucks with those drive shaft hand brakes and they are pretty useless. | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1228 Registered: 5-2001 Posted From: 65.74.65.209 Rating: N/A |
Gus, we have 30-30 pots installed on our coach. There are smaller ones made. It's always possible for a spring to break, so parking on a steep grade is not a good idea. I also noticed an Australian government spec to test spring brakes. They were required to stop a full load on a 20% grade and set the parking brake. If it held, the brakes passed the test. If one spring was broken, then the parking brake would not hold. If the brakes were way out of adjustment, they wouldn't hold, either. Years ago, when we bought a pump truck, we had to replace pots because the springs were broken. The replacement pots had vinyl coatings on the springs, probably to slow down the rust. I know of at least one case of someone loading a dumptruck with a backhoe and the truck took off down the hill when it was heavy enough. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Patrick levenson (Zubzub)
Registered Member Username: Zubzub Post Number: 27 Registered: 5-2007 Posted From: 64.229.55.234 Rating: N/A |
My handbrake stops the bus from 50 mph quite agressively. It's in good shape and adjusted well. I like the belts and suspenders lookm so when I have installed maxis I will keep the drive shaft brake as well, can't be too safe. | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1208 Registered: 10-2003 Posted From: 71.58.110.9  Rating: N/A |
The shorter pots will not fit in the space on 4106 or later models. They have about two inches less room than the shortest available pot requires.DD3's would be the best bet if you don't mind getting all the other components that go with that system from a donor vehicle. Could be expensive. Re fabricating the brake mounts is one possibility if done properly. The addition of recesses in the baggage compartment is quite feasible and will work well if done by someone that can perform the modification without causing weakness to the compartment. Remember to allow for clearance of brake cans when suspension is at full height, such as going over a big bump. BTW, that pic looks like the maxi's won't clear the bulkhead. Might be the angle OR maybe not. |
