electric air compressor tied into air system on bus

[kevink1955]

DOT allows school busses to have belt driven compressors. I feel safer with the Harbor Freight compressor and the operator glued to the air gauge than being around an International powered school bus.

Come on guys, I do not even own a bus. I joined because I have a intrest in restoreing old vehicles and this site impressed me greatly with the members that always helped out others when broken down.

Advise has been given, I am sure the original poster knows what he did with the external compressor may not have been right but was it any worse than an original compressor failing while out on the road?

I am sure the original low air warning still worked and if the bus has spring brakes they work also.

Move on and restore the site to the loving,helping that has drawn most of us here.

[gumpy]

Wow!

I guess it was probably wrong of me to fix my air system with a wine cork and continue on down the road, huh?

[thomasinnv]

If your going to act like you know every thing and claim it to be law, then don't get pissy when someone asks for the facts to back it up. 

I was trying to inject some humor into it.  "Is THIS your card?" is a running Penn & Teller gag.

if that be the case i must then apologize for my comments.  i failed to pick that up.

[Melbo]

Gumpy A WINE CORK -- I remember that post and I was mostly distressed that you didn't use a cork from IMPORTED wine but a cork from domestic wine --- these buses are IMPORTED from Canada and we need to use corks that are imported.

Melbo

[gumpy]

Gumpy A WINE CORK -- I remember that post and I was mostly distressed that you didn't use a cork from IMPORTED wine but a cork from domestic wine --- these buses are IMPORTED from Canada and we need to use corks that are imported.

Melbo

I was mostly distressed that I had a cork on the dash, and didn't have to open and finish a new bottle first!    Not that it's necessarily akin to import, but it was a cork from my
homemade wine. Maybe that's even more domestic than domestic wine.

[Busted Knuckle]

OK I admit I don't know the cfm rating on these compressors!

But I do know for a fact that the MCI 96A3 & 102A3 up through D models spec a TU-Flo 750 and not some 500, 550, or 600 found on any truck shop in the country!

And I know that in order to get one it takes 2-3 days we've had more than one fail and that is why I bought the great take out from Gumpy to have a core to send in for the re-maned that sits on the shelf now!

Just telling a truck shop it's for a 6V92TA means diddly squat except that the person on the other end of the phone knew less than you and I SURE wouldn't be buying from them! (must have been the same shop that told Cody "we don't work on weedeaters" when asked if they had any mechanics that knew about working on 2 strokes!)
  BK 

[Nusa]

I'm not taking sides, but I am interested in what the law actually says on the subject of air brake compressors. This is what I've found so far, at least at the Federal level:

Part 393.40: Required brake systems. http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.aspx?reg=393.40

(b)(2) Air brake systems. Buses, trucks and truck-tractors equipped with air brake systems and manufactured on or after March 1, 1975, and trailers manufactured on or after January 1, 1975, must, at a minimum, have a service brake system that meets the requirements of FMVSS No. 121 in effect on the date of manufacture. Motor vehicles which were not subject to FMVSS No. 121 on the date of manufacture must have a service brake system that meets the applicable requirements of §§393.42, 393.48, 393.49, 393.51, and 393.52 of this subpart.

What I find interesting here is that standard 121 doesn't even apply to older vehicles...they have to pass some performance tests, but are otherwise grandfathered.

Part 571.121: Standard No. 121; Air brake systems. http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.aspx?reg=571.121

S5.1 Required equipment for trucks and buses. Each truck and bus shall have the following equipment:

S5.1.1 Air compressor. An air compressor of sufficient capacity to increase air pressure in the supply and service reservoirs from 85 psi to 100 psi when the engine is operating at the vehicle manufacturer's maximum recommended r.p.m. within a time, in seconds, determined by the quotient (Actual reservoir capacity×25)/Required reservoir capacity.

S5.1.1.1 Air compressor cut-in pressure. The air compressor governor cut-in pressure for each bus shall be 85 p.s.i. or greater. The air compressor governor cut-in pressure for each truck shall be 100 p.s.i. or greater.

I fail to find any written requirement that air compressors be original equipment, engine-driven, or DOT certified, so long as they meet the performance requirements. I realize an actual DOT inspector could give you grief regardless of the law, but if there's an actual regulation/law against it, I haven't found it.

Perhaps I'm not finding the right documents? What else should I look at?

[Dreamscape]

Some of you might remember when our compresser failed when I was in Palm Springs moving to Texas back in 06. I was lucky to have a HF compressor, tapped it into the front port used for towing. I moved it off the Exit ramp and across the freeway to wait for help. It took forever to build air, but it did. Clifford and Sonja supplied me with a new compressor and I was on my way to Abilene to meet up with my wife and in-laws on Christmas day.

I was a amazed that it worked and thank goodness I had one. I would do it again the same way if it ever happens again. I got rid of the HF and bought a larger one from Sears. I haven't tapped into the air yet, but plan to.

[ruthi]

BK, that is funny about the weed eaters, but I believe it with the experiences we have had with truck stops. 

[artvonne]

  Ive read through this thread and many others, including the one by the guy whos leaving. Ive been on a few other forums, and after a while you see the same garbage, people so anal about things they make everyone want to leave.

  Here is the deal, and for those who wish we all followed the letter of the law read carefully. Laws are written more often to keep bureaucrats busy than anything else. Someone got hurt, a bunch of Mommy's got upset and said "there has to be a law", and there you go.

  But this is NOT Soviet Russia, and there is no Politico riding shotgun with me. I am free to do what I want, when I want, how I want. If you dont like it, tough. Call the law on me. Boy that would be funny. Officer, there is a bus running down the road with a non DOT approved air compressor on his RV running off a two bit air compressor. Boy, Ican see the blue light special coming after me from here.

  If and when I get a bus, I will endevour to make it fully roadworthy and fully road safe, as I do any vehicle. But dont read me the law about how best to get the damned thing to where I feel I want to get it to. If I could get it home safely using auxillary equipment that "I" determine to be adequate, I will do it. And thats it in a nut shell. Freedom to make your own decisions. If your an idiot, everyone will find out sooner or later. Id much rather have someone with a brain driving an antique bus down the road with a makeshift compressor with his eye on the gauge, than some moron millionaire in his million dollar coach that doesnt have a clue, regardless how "DOT" perfect his rig is. Some people just have no common sense.

[PSmith]

What he said !  (artvonne)

Maybe some of us that haven't posted much because of the Scrutiny.  I may decide to participate in the forum more often.  We're not a bunch of wreckless dingle-berries !.   I've spent 13 wonderful years working on my bus making sure that things are Safe and Fun.

  My judgement on things is All I need.  Reading others' opinions on different subjects gives me 'food for thought' and enhances my knowledge and makes me better informed - But that information will be weighed against what I already know and how it applies to my circumstances.  Not everything that is spewed from the 'almighty informers' will be correct

But I hesitate to chime in when there are 'over-bearing' - 'abrasive' - 'judgemental' folks who insist that everyone else 'tow the line' or be subject to their ridicule.

I say it'll be better now - (cautiously optimistic)

phil

[artvonne]

  So just how failure prone are these air compressors? Good idea to carry a spare? whats the going rate for a quality rebuilt?

[gumpy]

 So just how failure prone are these air compressors? Good idea to carry a spare? whats the going rate for a quality rebuilt?

Well, I bought a spare and carried it for about 8 years.  Never needed it. Needed a spare alternator, which I didn't have. But have not needed the spare air compressor.
So, the spare air compressor is now sitting in the garage. I'm going to box it up ready to ship. Then, if I need it while I'm away from home,
I can call my neighbor and have him ship it to me.

Oh, and I'm also going to get my HF air compressor installed in the bay and connected into the air system, so I can avoid the high shipping charges on that spare! 

[Paladin]

  Ive read through this thread and many others, including the one by the guy whos leaving. Ive been on a few other forums, and after a while you see the same garbage, people so anal about things they make everyone want to leave.

  Here is the deal, and for those who wish we all followed the letter of the law read carefully. Laws are written more often to keep bureaucrats busy than anything else. Someone got hurt, a bunch of Mommy's got upset and said "there has to be a law", and there you go.

  But this is NOT Soviet Russia, and there is no Politico riding shotgun with me. I am free to do what I want, when I want, how I want. If you dont like it, tough. Call the law on me. Boy that would be funny. Officer, there is a bus running down the road with a non DOT approved air compressor on his RV running off a two bit air compressor. Boy, Ican see the blue light special coming after me from here.

  If and when I get a bus, I will endevour to make it fully roadworthy and fully road safe, as I do any vehicle. But dont read me the law about how best to get the damned thing to where I feel I want to get it to. If I could get it home safely using auxillary equipment that "I" determine to be adequate, I will do it. And thats it in a nut shell. Freedom to make your own decisions. If your an idiot, everyone will find out sooner or later. Id much rather have someone with a brain driving an antique bus down the road with a makeshift compressor with his eye on the gauge, than some moron millionaire in his million dollar coach that doesnt have a clue, regardless how "DOT" perfect his rig is. Some people just have no common sense.

X2

[Rick59-4104]

 My attempt to turn this thread back to the positive, I can see the wisdom in replacing the compressor on my 4104 with a rebuilt one or pulling the one in the bus and having it checked out as I have no idea how long the one I have in has been in service...
I second and add to Artvonnes question, has any one rebuilt the original compressor in a 4104 or are you better off to buy a rebuilt one? What are the thinks to look for to tell if your compressor is in need of attention? If I was are getting a lot of oil in the drain tanks I know this would be a concern but what else should I look for? How much oil in the first tank is acceptable? The PO of the bus had been on 2 long cross country trips in my 4104 in the past 2 years and had just drained the tank in the front and did not know about the rear drain, when I drained it I got about 2 quarts of water and probably a half quart of really nasty looking oil.  Is this acceptable? I am thinking pulling the compressor and going thru it and maybe even the generator might be a good winters project.

Lets turn this into a helping thread for those of us new to these old buses. I, like a lot of people here do not have really deep pockets but am very much interested in the safety of my passengers and the other people on the road.

Artvonne, I enjoyed our visit and thanks for the kind words about my bus and place, keep in touch.

Rick