General Questions About Air Lines/Fittings

[luvrbus]

Belfert, I wasn't clear but he told me a coupling is not allowed no place in the braking system now per DOT. 
Not a big deal to us anyway if the DOT ever pulled most of us here on the board over for a check we would be sitting there with the nice sticker on the windshield LOL

good luck

[Melbo]

Any truck supplier has the DOT air line. Also as mentioned it is usually available at truck stops.

The price is also very reasonable the expense is the fittings.

Also as mentioned be sure to use the brass inserts when making connections.

Melbo

[buswarrior]

Find the leaks,
repair them,
use proper DOT materials,
take a course/read a book about air brakes.

Please don't drive the bus again until it has been confirmed to be safe.

If you feel the effect of those little loads in the braking, you've got no braking left.

happy coaching!
buswarrior

[zubzub]

shop around for the best supply place for DOT lines fittings. I found a local place that charges the same prices as the best
I can find online and the parts are there ready to go.  Also it's nice to support local business. 
i see no reason that there should be air leaking from a relay unless you have DD3 cans and associated relays.
As others have mentioned read up on adjusting brakes,slacks  etc...it's not rocket science....even I have woRked it all out.
BTW the dot comp fittings usually have pipe thread fittings on the other side....usual sizes 1/4" 3/8" 1/2" 3/4".  I have been using
a Loctite product for the pipe thread fittings, can't remeber it's name but it's spec'ed for air lines.  I actually would like to know the name of the orange stuff the dot fittings come with as it seems more"Dotty"(Dotish?).
p.s. don't use thread locker/sealer etc on the comp side of fittings.

[Depewtee]

Thanks for all of the replies to date.  I spent this afternoon finishing my ramps, so I can safely crawl under the bus and start troubleshooting/repairing air lines and fittings.  I did manage to reach under the bus and snap a few pictures of the trouble area.  Forgive the focus, but I could not look through the viewfinder with the limited amount of room I was working with.  I have posted the pictures on photobucket.

[zubzub]

The small line with the kink in it looks like it's running to the air levellers, but make sure that is the case.   Mostly you need to get up in there (after safely blocking the bus/ I also put blocking between axle and body so if an air bag looses pressure the bus does not sit on me) and work it out.  
BTW my previous post did not consider that the relay itself could be at fault, if it is just pissing air all the time I would imagine it was the diaphragm in the relay.  It is inexpensive to by a new relay...any truck store, look up what kind you have online with pics etc...
If you want to be really cheap maybe you can rebuild the one you have ...but I wouldn't and I am pretty inexpensive.....but these are brakes and I don't mess around with being cheap on safety stuff.

[kyle4501]

Someone mentioned the 'push-in' fittings. We use them at work on the machinery we build.
While there are DOT air brake approved "push-in" fittings, they'd be my last choice. The compression fittings are better due to the way they seal the fitting to the hose - the nut compresses a ferrule into the tube. A push-in fitting relies on an o-ring to seal against the tube.

Push-in fittings are more prone to leaking due to:
- When the o-ring dries out.
- The tube scratches the o-ring.
- Scratches in the tubing.
- If there is any twisting on the air line, the push-in fittings tube retention clamp can dig into the tubing . . .

We use the push-in fittings because they are cheaper for us. The assembly labor is where we save $$, they seal OK at first, but develop leaks faster over time than the quality compression fittings. And besides - we aren't the ones paying for air leaks in the field. . . . 

[zubzub]

and they are hard to open and reuse.

[Depewtee]

After replacing the air line that had the kink in it I started the bus, let the air pressure come up, and watched the rear bags fill.  I consider this a temporary fix, as the rest of the lines and fittings need to be redone/replaced (thanks Bob for the PM).  As you can see in the picture below, taken prior to fixing the kink, the original leveler valves have been bypassed.



The levelers have been replaced with a valve and switch system that allows the rear bags to be deflated to level the bus while parking.  I have a lot of work to do on this system, but I am now leaning towards keeping it (I know at a minimum it needs the clear lines replaced with DOT approved lines).  Any thoughts on this system versus the stock leveler system?



My newly built ramps work really well. 





The tires on the tag axle are suspended in mid-air and I noticed they spin freely.  Should this be the case?  Or should the brakes be applied on them when the park brake is engaged? 

I looked around at the rest of the brake system trying to familiarize myself with the different components. I am going to have to do some reading to figure everything out.  I will heed the advice of many and take the bus to a professional garage and have them inspect the brake system before taking it back out on the road.

With the rear of the bus elevated I had a better chance to look at the valve that is leaking air.  I noticed that it looks like the center section of the valve is held in place by a clip. Is replacing this part as simple as removing the clip, sliding out the old center section, and reinserting a new one?





While looking around under the bus I also noticed what appears to be a plug missing from the area of the flywheel.  Should this hole be empty?  The engine is a 6V92-T with an Allison automatic transmission.



Thanks again for all of the advice to date,

Brian S.

[Busted Knuckle]

OK first is the question on the brakes.
The only brakes that are "set" by the parking brake are the "Drive" axle brakes.

On the valve question no it is not that simple (too bad, it's be nice). The clip youy see is there to hold part of it in place and can be removed to rebuild the valve if you had a "kit", which is sometimes a better option of just replacing if it is a hard to find part.

The plug missing in the bell housing is common, and OK. Many yrs ago some buses came with "wet" clutches, and on one of those if the plug was missing you would be in serious trouble by now!

On the leveling system if it were me, I'd definitely rehook the valves adn use the stock system while traveling. But I would tie your system into it also for leveling it while camping! (there are others on the board who have done great things with air leveling systems!) 

And on the clear tubing, yes I would replace it with DOT approved tubing!
FWIW   BK 

[John316]

On that relay that is leaking...That sounds to me like one of your diaphragms in one of your brake can's has a hole in it. The pic confirmed what I thought, that it is the same relay.

We have been there, done that, and I do know what you need to get the brakes fixed.

God bless,

John

[Bestekustoms]

Brain,  GREAT TOPIC, GREAT POSTS.

You Seem Like The Kinda Guy That Will Get It Fixed RIGHT.
Your Curious And So Am I.
As You Go Through Your Air Problems...We ALL Learn From That. I Have Really Enjoyed All Of The Posting On This Thread. I Am Also Kinda New To Some Of The Systems And Makeup Of Our Great Hobby.I Had My Air Brake Endorsement Many Years Ago When, I Drove MCI Coaches For A Charter Company Here In Colorado.So,This Is A Great Refresher For Me.
If You Dont Use It....You Loose It.!!  10-4

Hey,By The Way....Great Looking Ramps You Have There

Good Luck.  I Look Forward To You Posting More Pictures And Getting The Ole Girl Back On The Road Safely..
JOHN

[Depewtee]

Hi Everyone!

I took the advice of many on this board and took my bus to a professional bus garage to have the brake system inspected. I picked it up today and I must say I am pleased with the results.  The garage I used was located at Good Time Tours in Pensacola, FL (about an hour drive from my house).  Mr. Roy Wassmer is the Service Manager - 850-476-0046.

To recap the story and this thread, I am going to copy/paste from portions of the service request I provided Mr. Wassmer.

Dear Mr. Wassmer and Good Time Tours Service Technicians,

Short Version: The TR-2 Inversion Valve is releasing large amounts of air causing the bus to lose all air within five to ten minutes of being shut off.  I have been told this may be the result of a leaky diaphragm in a brake canister.  Please inspect the brake system and adjust/repair for safe operation.

Long Version:  I bought this bus back in July.  It is the first bus I have owned and, although I am somewhat mechanically inclined, I believe working on the brake system should be left to professionals.  I bought the bus from an individual in Minnesota and drove it back the 1,400 miles with no issues.  Since July, I have driven it once every week or two in the local area (usually no more than 50 miles).  On one my outings I had to make a quick, hard brake application causing one or more of the rear wheels to lock up momentarily (not sure this has anything to do with any problems, but I thought I would mention it in case it did).  Last month I drove the bus to Talladega for the weekend.  It is the first time I had the bus loaded (100 gallons of water, 140 gallons of fuel, 4 adults, and enough food/supplies to survive in the infield of Talladega for four days).  I noticed when driving the bus that it seemed to take longer to stop than before.  I attributed this to the loaded condition.  After unloading the bus it still seems to take longer to stop than it did before, although it could just be my imagination.

The main reason for me bringing the bus to you is to inspect/repair/adjust the brake system.  There are some other issues with the bus that I would like an estimate on repairing.  The previous owner disabled the automatic levelers and installed a series of switches and air valves to allow the bus to be leveled while camping.  What would it cost to install new levelers and hook the factory system back up?

The valve that adjusts the tension on the fan blower belt is leaking air.  What is the cost to inspect/repair/replace this valve?

I was told by the previous owner that all filters were changed in December 2008.  While they look new, I cannot attest to the accuracy of this claim.  What is the cost to replace the fuel filters? Oil filters? Air filter?  Any I am missing?

The previous owner also stated that he did regular oil analysis on the motor oil, but he did not provide copies of any of the results.  What is the cost for an oil analysis?

Please call (XXX-XXX-XXXX) or e-mail with any questions.  Also, please feel free to call or e-mail if you notice anything unsafe and/or in need of repair on the bus.  I cannot afford to make the entire bus new, but I do want it to be safe.  We do not plan on putting more than 3,000 to 5,000 miles per year on the bus (waiting for retirement to do the big travelling).  We are planning our first family trip for the middle of December that should be less than 1,000 miles. 

Thank you in advance for all of your assistance,
Brian

Mr. Wassmer was very good about calling me and providing me updates and estimates.  Below is a list of some of the work done.

1. Replaced rear air tank with used one.
2. Replaced brake shoes, wheel seals, hub seals, and axle gaskets on drive axle.
3. Replaced brake chamber on left side drive and replaced four air hoses going to both brake cans on drive axle.
4. Replaced governor.
5. Replaced valve for belt tensioner.
6. Replaced R-12 valve for brake system.
7. Changed oil and oil filter.
8. Replaced both fuel filters.
9. Added one gallon of Dexron III to tranny.
10. Greased coach.
11. Replaced left side drive axle brake drum.
12. Rebuilt brake chamber on right side drive axle.

It turns out the left side drive axle brakes were frozen in the open position.  Apparently years of ice, snow, salt, etc. took a toll on them.  Upon further inspection they found that the left side drive axle brake drum had a crack in it.  Mr. Wassmer said it was not a stress crack, but appeared to be a crack caused by someone striking the drum with a hammer or similar object (likely trying to loosen the brakes).  He had an old coach in his yard and pulled a brake drum off it and sold it to me for $140.  They also found that the air tank for the brakes had a lot of rust and actually had a hole in it.  Again, they went to the old coach in the yard and pulled the air tank from it and sold it to me and installed it for $100.  I have a parts list two pages long of other smaller items they changed (i.e., bolts, washers, diaphragms...).  The total bill was quite high (don't ask), but I was kept informed the entire time of the charges and approved them as new issues were found.  The bus stops really well now. 

Mr. Wassmer stated that the engine sounded good, idled well, and had a lot of power.  He went on to recommend a Detroit Diesel shop in Panama City in the event I ever needed any engine work.  He also mentioned that my coach "rode rough."  He attributed it to the levelers not being hooked up.  He also mentioned a slight hesitation in first gear when starting after coming to a stop (the previous owner told me of this and insured me an Allison transmission service center inspected it and found nothing wrong.  Additionally, Mr. Wassmer did not find it to be an issue, although he did advise me to monitor it).  I will make separate posts for the "ride" and the "transmission" issues later and seek advice on those separately. 

The labor rate charged was $30 per hour.  As an example, they charge $180 for an oil and filter change (that includes the oil and filter - $87.18 for 24 quarts of Dello 400 SAE 40 and $16.39 for a B95 oil filter).

Brian S.

[JackConrad]

The missing plug in the bellhousing is so you will know if you have a transmission front seal or torque converter or engine real seal leaking. That is how I knew I needed to replace my front seal. Jack

[buswarrior]

Sounds like you have found a good shop manager.

Communication is key, and being able to work with you on prioritizing a budget is hard to find.

Would you mind posting the total, with the taxes noted?

Never mind what price someone can get from their lodge buddy to do half the job, if you are happy, were well treated, lots of advice and knowledge shared and the job done thoroughly, that doesn't come free,  stay happy!

Other busnuts would benefit to see what this collection of good repairs, to get the coach road ready and SAFE, will cost.

happy coaching!
buswarrior