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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: pennuja on September 22, 2014, 12:24:53 PM

Title: 4104 unable to move
Post by: pennuja on September 22, 2014, 12:24:53 PM
I tried to pick up my new to me 4104 today and it went much better than I anticipated with one exception.

We installed 2 new batteries and were able to get it started without too much trouble, it has been sitting for five years. After running on high idle for a few minutes the air pressure came up to 110 and I tried to release the parking brake, from what I can tell there was not a service brake like I have seen on some other coaches. The coach was sunken into the ground from sitting so we pulled it a few feet back so that I did not have to try to move it out of the ruts (The PO had just installed a new clutch before parking it and I did not want to
chance messing it up getting out of the ruts) and it seemed to move fine, I do not know enough about the brakes but it would seem that the brakes are not locked up. I did try to set and release the brakes by picking up on the parking brake switch to the right of the drivers seat, I also tried pressing and releasing the regular brake pedal. I do not remember seeing a specific procedure in the operators manual but could easily have missed it.

Does anyone have any suggestions on what to try when I go back tomorrow, maybe something to look for I really do not want to damage something by doing something stupid?

Thanks in advance,
Jim
Title: Re: 4104 unable to move
Post by: mung on September 22, 2014, 01:25:58 PM
If you can move the bus by pushing it while it is in neutral and the tires are turning, it isn't the brakes.  Is the engine lugging when you let out the clutch?
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 01:38:14 PM
When I let out the clutch the bus starts to move (very slightly) but the clutch starts to chatter, I am not applying the accelerator pedal at all just slowly releasing the clutch.

The engine does seem to slow when releasing the clutch, I did not try very much I was afraid of doing damage. I figured it best to ask here first and try again tomorrow when I have more time.


Title: Re: 4104 unable to move
Post by: luvrbus on September 22, 2014, 01:46:11 PM
You released the pedal all the way at idle and it did not stall the engine ?
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 03:22:01 PM
No not all of the way out the bus started to shake and seemed like it would stall and I stopped at that point, I was running out of time and needed to get back home so I figured I would just make sure I released the brake correctly before trying farther.

Title: Re: 4104 unable to move
Post by: luvrbus on September 22, 2014, 03:32:30 PM
It's a high geared 1st in a GM the chatter is normal for a bus setting for 5 years even here in the desert you get rust on the clutch disks and flywheel on a GM go for it you will be fine that 6-71 does not have enough power to tear up anything 

I can almost guarantee the engine will stall first before it moves at idle ::)
Title: Re: 4104 unable to move
Post by: bobofthenorth on September 22, 2014, 03:34:41 PM
You could possibly have pulled it back against an applied brake - unlikely but possible I guess.  Did you try pulling it ahead?

(I see Clifford - AKA BusYoda - has already told you what to do - trust his word.  He's forgotten more about buses than I will ever know)
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 03:34:58 PM
Should I try to give it some accelerator pedal to move it or see if it stalls first?
Title: Re: 4104 unable to move
Post by: luvrbus on September 22, 2014, 03:40:09 PM
To get it to move it will need throttle it's going no where at idle
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 03:42:11 PM
Thanks so much for the info!
Title: Re: 4104 unable to move
Post by: eagle19952 on September 22, 2014, 03:48:00 PM
just because....check the clutch adjustment...how much free pedal ?
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 03:51:55 PM
Thanks eagle I have the manual I will look it up.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 22, 2014, 04:12:46 PM
Quote from: pennuja on September 22, 2014, 03:51:55 PM
Thanks eagle I have the manual I will look it up.

and linkage.... ;)
Title: Re: 4104 unable to move
Post by: bevans6 on September 22, 2014, 04:27:24 PM
If you can stall the engine with the clutch, then you have some clutch.  It won't hurt anything to stall the engine.  Then, put the whole dead throttle start away for a minute, and try to move the thing like it was a Toyota.  Rev the engine, in gear, balance the clutch against the load, and see what it can do.  Dead throttle starts are fine with a great engine and clutch on flat ground, but I have my idle set low and I can't do dead throttle anything if there is a 1% grade or a dead squirrel in the way...

Stop when the clutch either makes smoke or you can smell it, that is getting to the too much point...

Edit; clutch smells like "oh crap what have I done" and "that is going to be expensive"...  It usually isn't, they built these things for ruder guys than we are...  You'll probably just clean off the rust.

Brian

Title: Re: 4104 unable to move
Post by: mung on September 22, 2014, 04:40:14 PM
You know, probably the most important thing here.  Where is the bus and what is the serial number?  Is it a conversion?
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 04:41:26 PM
Thanks Brian, like usual I think I ended up doing too much research, and was being way to safe.

Hopefully tomorrow I can bring it home.
Title: Re: 4104 unable to move
Post by: pennuja on September 22, 2014, 04:49:47 PM
Quote from: mung on September 22, 2014, 04:40:14 PM
You know, probably the most important thing here.  Where is the bus and what is the serial number?  Is it a conversion?

It is a conversion from the 70's it is bus number PD4104-3856 I will post some pictures once I get it home, I was so busy working on it today that I forgot to get them.

I think that I am the 3rd owner since the conversion and neither of the PO's did any updating cosmetically to it, just mechanical maintenance.

Here is a picture from around 10 years ago it currently looks exactly the same just more faded and the paint is flaking off on the roof and side stripe.

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2Foldpictures140.jpg&hash=c0b08902ca3382d19851d61b6fbb720a78db311c) (http://s76.photobucket.com/user/pennuja/media/oldpictures140.jpg.html)
Title: Re: 4104 unable to move
Post by: mung on September 22, 2014, 04:59:27 PM
Looks nice.
Title: Re: 4104 unable to move
Post by: Jim Eh. on September 22, 2014, 07:48:43 PM
If you burn out the clutch just moving it from that point, it is likely a bad clutch to start with. Those suckers last hundreds of thousands of miles.
Title: 4104 unable to move
Post by: pennuja on September 23, 2014, 12:01:51 PM
Tried again today and it would seem that there is an injector that is not working correctly. Yesterday the bus ran ok after being in high idle for a minute, but today I was unable to put it on high idle whenever I did lots of black smoke would come out and the engine would idle very rough.

We replaced the fuel filter and added in some kerosene when we primed it. After doing this twice the engine would idle very well but still no high idle and stepping on the accelerator pedal would just smoke as well.

Does this sound like a stuck/clogged injector? What would be the best course of action at this point?
Title: Re: 4104 unable to move
Post by: gumpy on September 23, 2014, 12:46:25 PM
Did you trip the emergency shutdown flap?


So, I'm guessing you bought this bus without ever test driving it?  You must have got one screaming good deal on it. Either that, or you're just about a crazy as the rest of us!
Title: Re: 4104 unable to move
Post by: pennuja on September 23, 2014, 12:58:29 PM
Quote from: gumpy on September 23, 2014, 12:46:25 PM
Did you trip the emergency shutdown flap?


So, I'm guessing you bought this bus without ever test driving it?  You must have got one screaming good deal on it. Either that, or you're just about a crazy as the rest of us!


I did not trip the flap, is this how it would run if you did?

Definitely crazy like the rest it is a good bus and ran well a while ago but you know how that goes after sitting all bets are off.
Title: Re: 4104 unable to move
Post by: Rick 74 MC-8 on September 23, 2014, 01:24:05 PM
Most likely lack of air. Check the air breather and blower intake. Might of sucked in a rodent
  Rick
Title: Re: 4104 unable to move
Post by: Lin on September 23, 2014, 01:29:57 PM
Activating the emergency shut down would act like that.  It's just a big disk in the air intake that closes off air flow to stop a runaway.  However, enough air does get by to let it idle.  You just reset it by hand in the engine bay.

I assume you will have DD3 brakes.  Just in case you did not know, merely releasing the parking brake valve does not release the brakes.  You need to apply full force to the service brake pedal after the parking valve is released to unlock it.
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 01:34:07 PM
Was that parking brake setup something on later 4104s?  Mine has the handle that controls 2 huge pads on the output shaft.
Title: Re: 4104 unable to move
Post by: pennuja on September 23, 2014, 01:42:02 PM
Thanks Lin I read that yesterday about the brakes and was going to try that today. I will definitely check the emergency shut down.

Mung you are right I am pretty sure mine had the handle and someone removed it but I could be way off.
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 01:48:35 PM
Are there any big vehicles on site that you can use to pull it out or at least help to pull it out?  Otherwise, what about using a come-along or winch?  If you can get it to move with some other source of power, then it isn't the brakes or anything like that.  Are the tires nice and aired up?  Get them as full as possible if you want them to roll easy.

http://www.harborfreight.com/8000-lb-cable-winch-puller-543.html (http://www.harborfreight.com/8000-lb-cable-winch-puller-543.html) should be beefy enough to pull you out.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 01:52:57 PM
In your original post #1...you said you pulled the bus out of the ruts....were the wheels turning ot were they dragging ?
Title: Re: 4104 unable to move
Post by: pennuja on September 23, 2014, 02:25:17 PM
I have it on flat ground now and aired up the tires today they were quite low. I think it should move now once I get it running again, I am going back again tomorrow and the first thing that I am going to check Is they emergency shut off. I also have a mechanic coming to check things out so hopefully I will get it going.
Title: Re: 4104 unable to move
Post by: pennuja on September 23, 2014, 02:26:17 PM
Quote from: eagle19952 on September 23, 2014, 01:52:57 PM
In your original post #1...you said you pulled the bus out of the ruts....were the wheels turning ot were they dragging ?
I was told that they were all turning, I was steering the bus so I was unable to see.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 03:45:50 PM
Quote from: pennuja on September 23, 2014, 02:26:17 PM
I was told that they were all turning, I was steering the bus so I was unable to see.

I believe they were too...so eliminate locked brakes/brake problem as the problem...
as far as engine speed....do you have a tach ?
i assume that it was screaming....so regardless the color of smoke ,assuming it was running on at least all but one cylinder....it should move.
IMO that leaves the clutch.
I'll re read your post..
Title: Re: 4104 unable to move
Post by: pennuja on September 23, 2014, 04:22:07 PM
Quote from: eagle19952 on September 23, 2014, 03:45:50 PM
I believe they were too...so eliminate locked brakes/brake problem as the problem...
as far as engine speed....do you have a tach ?
i assume that it was screaming....so regardless the color of smoke ,assuming it was running on at least all but one cylinder....it should move.
IMO that leaves the clutch.
I'll re read your post..

That is the thing, I do have a tach and I tried today to rev the engine to move it but when I push on the pedal it moves to the floor but does not make much of a difference other than lots of black smoke. I am hoping that the emergency shut off flap is closed and that solves it but it seems too easy. I had the PO get in back and watch when I push the pedal and you can see the cable move on the governor but very little reving happens, the more I describe it the more it does sound like it could be the shutoff.

I found the emergency stop choke switch in the operators manual so I know what to look for. There is a switch on the right instrument panel that says emergency stop does this activate the same flap because if is very possible that someone could have pressed it while it was not running.

Edit... Since I have been thinking more about it I guess that the issue could also be air filter related since it idles but does not rev up, we never opened up the air filter to even check if it was ok.

Thanks again for everyone taking the time to help me out it is very much appreciated.
Title: Re: 4104 unable to move
Post by: chessie4905 on September 23, 2014, 05:33:55 PM
   You have to reset the flap manually at the engine. It is spring loaded. Flipping the emergency stop switch releases it, but does not reset it. You need to rotate the little wheel till it latches behind the pin on the solenoid(about the size of a GM starter solenoid; mounted vertical with a shaft pointing down. at the inlet housing. Sure sounds like your problem.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 07:06:09 PM
here's a flappper latch....yours will be solenoid applied and hand reset...this one would be cable activated, hand reset.
this one is not loaded/cocked....it has been applied.

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.thedieselstop.com%2Fforums%2Fattachments%2Ff33%2F14158d1335566600-detroit-diesel-6v53-img_8717.jpg&hash=4beab01e207a00d505ee99103b4c59a6d022abf8)
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 07:18:49 PM
That doesn't look anything like mine on my 4104.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 07:22:27 PM
then find a better picture....it's atypical... :-\ better yet go take one..

ps it takes air to make black smoke...

Note:  the black smoke of both the push truck and the Phoenix is normal.  They over fuel the engine to produce the huge amounts of power.  The first time I saw the Phoenix run, I thought it had caught fire.

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Frvsafetysystems.com%2FPhoenix%2520and%2520Peterbuilt%2520%28Small%29.jpg&hash=ad079b5992a8ffa68107cede2ec92e477336fcad)
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 07:30:22 PM
Hopefully you can see this.  On the right side of the blower intake there is a solenoid and below that is the cam for the flap.  When the solenoid lifts the cam is released and closes the flap.  You lift on the solenoid plunger, then with the little handle on the cam rotate it past the plunger on the solenoid and drop the plunger so that it holds the cam.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 07:33:24 PM
looks like your engine fell on it's face .... ;D
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 07:34:34 PM
Yeah, trying to get it to go in the right direction.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 23, 2014, 07:37:37 PM
horizontal, crankshaft perpendicular to the wheels in 4104....not atypical ...  ::)
Title: Re: 4104 unable to move
Post by: mung on September 23, 2014, 07:40:46 PM
It is part of that whole angle drive thing.
Title: Re: 4104 unable to move
Post by: uncle ned on September 24, 2014, 01:51:40 PM


Dang  that truck looks like huggy

uncle ned
Title: Re: 4104 unable to move
Post by: gus on September 24, 2014, 04:01:02 PM
The original 4104 has a black button that is strictly for emergencies. It uses air and is not for parking.

If the bus is aired and this button pulled out the rear brakes are locked. With no air they do nothing.

This is not a spring parking brake.

A Maintenance Manual is absolutely essential to answer questions about this bus and a Parts Book is almost as important to give you a picture of problem assemblies.
Title: Re: 4104 unable to move
Post by: luvrbus on September 24, 2014, 04:41:42 PM
4104 and early 4106's had ICC brakes if your brakes say not for parking then you have the ICC brakes like Gus said no air no parking brakes 
Title: Re: 4104 unable to move
Post by: mung on September 24, 2014, 05:15:39 PM
Do you know when they started that on the 4104s?  I don't see any sign of that on mine.  I have a big handle to the left of my seat that pulls back.  Did the later ones have that?
Title: Re: 4104 unable to move
Post by: eagle19952 on September 24, 2014, 05:56:46 PM
somewhere back in the thread/post he said that they pulled the bus and the wheels turned....would seem that the  brakes are released...
Title: Re: 4104 unable to move
Post by: pennuja on September 24, 2014, 05:57:46 PM
Thanks to all of the help from here I have my bus safely at home. The emergency shut off was definitely the cause of the bus not moving and not running correctly. After reseting the emergency shut off it started right up and reved up perfectly, however I do have a small issue with idling my idle seems to go up and down constantly.

I can without a doubt say that the black switch is not an parking brake or mine is not working correctly. I was cleaning out the basement storage and the bus started to slowly roll away after about an hour of it sitting there, luckily I was able to jump in quickly enough to put it into first gear and stop it.

I also found out that I am completely unable to downshift from any gear. I read RJ's shifting guide but due to where my bus was I did not have a chance to even try to figure out the shift points. I will need to read through it again and practice by my house where the roads are empty. I can without a doubt say that it was the most fun that I ever had driving I am sure I was smiling ear to ear the whole time.

Thanks again everyone that helped me out!

Jim
Title: Re: 4104 unable to move
Post by: eagle19952 on September 24, 2014, 06:04:39 PM
i still think you have shifter linkage and/or clutch adjust problems...
does this have a twin disc or single disc ?
does it have a clutch brake ?
i guess i could go read the book cuz i don't have a 4104 to look at... ;D
Title: Re: 4104 unable to move
Post by: pennuja on September 24, 2014, 06:08:23 PM
Quote from: eagle19952 on September 24, 2014, 06:04:39 PM
i still think you have shifter linkage and/or clutch adjust problems...
does this have a twin disc or single disc ?
does it have a clutch brake ?
i guess i could go read the book cuz i don't have a 4104 to look at... ;D

I am not sure about the single/double disc but it does shift up really well, I think I just need to learn to down shift. I tried everything but I stink at it. I am able to get it to go into first when I am rolling slowly but that is it. There could certainly be something wrong with the clutch adjustment I will try to check it out tomorrow night.

I am uploading a few pictures of it from tonight, I will post them soon...
Title: Re: 4104 unable to move
Post by: gumpy on September 24, 2014, 06:15:07 PM
Downshifting is an art of matching the engine speed to the gear speed. Most likely, you are not applying enough throttle when downshifting. Eventually, you'll get it.

I am concerned for your safety (and that of others), though, if the bus started rolling away after you had parked it. I do hope you chock the wheels until you get the whole parking brake
thing figured out.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 24, 2014, 06:15:44 PM
keep your rpm's up....and your chin... ;)
i will look in the book here soon

edit. no clutch brake, single disc..do you recall the free pedal amount ?
Title: Re: 4104 unable to move
Post by: pennuja on September 24, 2014, 06:23:39 PM
Quote from: gumpy on September 24, 2014, 06:15:07 PM
Downshifting is an art of matching the engine speed to the gear speed. Most likely, you are not applying enough throttle when downshifting. Eventually, you'll get it.

I am concerned for your safety (and that of others), though, if the bus started rolling away after you had parked it. I do hope you chock the wheels until you get the whole parking brake
thing figured out.

Yeah chocking the wheels is a definite until I figure out a better solution. It was a frightening experience and will never happen again, if I did not get in there at that moment the bus would have ended up in the lake (no one would have been hurt). The PO had used that as the parking brake but it obviously is not.

Definitely not enough RPMs I know that for sure, I was also in traffic going light to light so there was a lot going on and to much to safely try anything that kept me from concentrating on the road.
Title: Re: 4104 unable to move
Post by: eagle19952 on September 24, 2014, 06:31:25 PM
one thing that works for some .... concentrate shifting between 1st 2nd 1st till you get it then add 3rd... the add 4th... ;)
Title: Re: 4104 unable to move
Post by: pennuja on September 24, 2014, 06:39:34 PM
Here are some current pictures...

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8541.jpg&hash=5174513898ccdeafe96af51e109c0d140bf9c769) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8541.jpg.html)

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8543.jpg&hash=331382bdb3d55318ce88ae65e9cf4c9a33bebb49) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8543.jpg.html)

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8545.jpg&hash=454a5a7cc7f417add8c851e892da613c645233f6) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8545.jpg.html)

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8549.jpg&hash=901c332967d9885cff74c8e2c2c961f37815cdca) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8549.jpg.html)

I believe that the area that the silver mesh covers is the location of the real parking brake.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8552.jpg&hash=1b6e15e5c7af4a99ee0772e9159124f319ffac6b) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8552.jpg.html)

Here is a horrible picture of the two air brake buttons that I have, only the one does anything.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8550.jpg&hash=613bed9522c92be4c21c587b6aba56969fb0ffff) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8550.jpg.html)

Here is a very dark picture of the front of the bus.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi76.photobucket.com%2Falbums%2Fj2%2Fpennuja%2F20140924-DSCF8553.jpg&hash=97110fd0704ffb1868b544c13c01e0de1f79d9d1) (http://s76.photobucket.com/user/pennuja/media/20140924-DSCF8553.jpg.html)
Title: Re: 4104 unable to move
Post by: luvrbus on September 24, 2014, 06:46:49 PM
You are not the 1st to chase a 4104 when the air pressure drops  ;D
Title: Re:
Post by: digesterman on September 24, 2014, 07:01:36 PM
Good luck with your new project, you're fortunate that others here with experience with your bus model are so willing to share their knowledge, you're in good hands.
Title: Re: 4104 unable to move
Post by: usbusin on September 24, 2014, 08:27:35 PM
From the position of the driver side mirror it was never a hound!

GaryD
Title: Re: 4104 unable to move
Post by: mung on September 25, 2014, 04:24:09 AM
Why do you say that Gary?
Title: Re: 4104 unable to move
Post by: usbusin on September 25, 2014, 06:14:14 AM
Hounds had the drivers side mirror low like on the passenger side.  See my avatar picture; drivers side mirror high; never was a hound.  Original customer was a private bus company.

GaryD
Title: Re: 4104 unable to move
Post by: chessie4905 on September 25, 2014, 07:45:13 AM
See this:http://www.busconversions.com/bbs/index.php?topic=972.0;wap2

I notice that you have two buttons? One maybe just for holding on a hill and the other is a true parking/ emergency brake.
You also need to remove the screen and see if the rear brake chambers have three hoses going into each one. Do you also have an emergency brake lever? If so, it applies shoes to a brake drum on drive shaft. If it does, don't apply it for the FIRST time where you don't want to be stuck in case it freezes up from lack of use.
The shifting characteristics change as the transmission warms up to hot. Faster shifting when cold and slower towards hot. When pushing in the clutch when hot, it can take 20 to 30 seconds for gears to stop turning so you can engage first. They should eventually stop with clutch in(sooner when cold). If not, then some clutch adjustment or more to stop it from dragging. A dragging clutch can exasperate changing gears. Is that a tach in top center of dash cluster?
Title: Re: 4104 unable to move
Post by: mung on September 25, 2014, 08:02:07 AM
High and low like the ones on my ex-greyhound?  I guess there is an exception to every rule. 
Title: Re: 4104 unable to move
Post by: luvrbus on September 25, 2014, 08:03:54 AM
I help the GM guys with the ICC brakes we just remove the old bar weld brackets for a spring brake, reline the old drive line brake install a Bendix toggle switch on the dash and be done with it then when you lose air pressure the brake applies on it's own plenty of room to install a spring brake canister on a 4104 and the pre DD3 4106 systems
Title: Re: 4104 unable to move
Post by: eagle19952 on September 25, 2014, 08:55:46 AM
Quote from: luvrbus on September 25, 2014, 08:03:54 AM
I help the GM guys with the ICC brakes we just remove the old bar weld brackets for a spring brake, reline the old drive line brake install a Bendix toggle switch on the dash and be done with it then when you lose air pressure the brake applies on it's own plenty of room to install a spring brake canister on a 4104 and the pre DD3 4106 systems
good idea....i don't do so well in the 40 foot dash any more  ;D
Title: Re: 4104 unable to move
Post by: mung on September 25, 2014, 08:59:47 AM
Why did they stop using the hand brake on the 4104s? 
Title: Re: 4104 unable to move
Post by: luvrbus on September 25, 2014, 09:05:18 AM
They never did it carried over into the 4106's
Title: Re: 4104 unable to move
Post by: mung on September 25, 2014, 09:24:19 AM
So I guess someone took his hand brake out?
Title: Re: 4104 unable to move
Post by: eagle19952 on September 25, 2014, 09:42:43 AM
Quote from: mung on September 25, 2014, 09:24:19 AM
So I guess someone took his hand brake out?

perhaps the maxi mod is already in place...and the extra button is not yet deciphered...??
Title: Re: 4104 unable to move
Post by: luvrbus on September 25, 2014, 09:46:06 AM
The maxi will hold without air but you apply pedal pressure before setting the other knob is for the front brakes 
Title: Re: 4104 unable to move
Post by: pennuja on September 25, 2014, 11:41:19 AM
So do I need to either hold the pedal down and apply the button, or try the many many buttons that I still do not know what they do.

Where would the maxi mod wire connect to maybe I can back trace it to a button.
Title: Re: 4104 unable to move
Post by: luvrbus on September 25, 2014, 12:31:05 PM
Maxi brakes don't use electricity I doubt you have the maxi brakes they were just a miniature version of the spring brake a photo of the front and rear air chambers it's easy to tell what you have
Title: Re: 4104 unable to move
Post by: chessie4905 on September 25, 2014, 12:41:16 PM
   We installed spring brakes on our 4104. Easy to do and clear the body unlike the 4106 and later models. We also removed the brake drum and hardware off the driveshaft, which was a pita any time you wanted to service the driveshaft, u-joints, diff. transmission or clutch. That other button may have been used to hold coach on a hill while waiting for a stoplight.
Title: Re: 4104 unable to move
Post by: mung on September 25, 2014, 12:54:20 PM
On the note of holding the brakes for a long time at a light or something, is the correct procedure to engage the hand break so you don't eat up all of your air?
Title: Re: 4104 unable to move
Post by: luvrbus on September 25, 2014, 02:34:44 PM
No the only pressure drop should be at first application then it should start building up again if the pressure keep dropping you have major leaks ::)
Title: Re: 4104 unable to move
Post by: eagle19952 on September 25, 2014, 07:20:33 PM
Quote from: luvrbus on September 25, 2014, 02:34:44 PM
No the only pressure drop should be at first application then it should start building up again if the pressure keep dropping you have major leaks ::)

double  ::) ::)
fix the leaks and measure the recovery time....or forget seattle and san francisco...or better yet, follow me... ;D
Title: Re: 4104 unable to move
Post by: mung on September 26, 2014, 05:05:49 AM
I haven't really tested it yet, I will do that today.  Just like other things, I need to learn how not to drive again.  I tend to pump breaks on cars and that won't work on the bus.
Title: Re: 4104 unable to move
Post by: yvan on September 26, 2014, 05:14:54 AM
Vern in this months magazine there is a good article on Air Brakes.