I just bought a 72 silver eagle conversion bus, it has been sitting for several yrs and I thought the brake shoes were stuck to the drum. But I think the parking brake won't release, the brake light on the dash is still on when I try to release brake. Air gauge reads about 67 psi, is this normal? the parking brake button says to release brake at 100 psi, there is no air leaks that I can hear. Anybody have any ideas? Thanks for reading this HELP!!
air should go to aprox 120 max before stopping.
air goes to the 67 mark pretty quick and just stops no matter how long you run the engine, but I don't hear any air leaks. Is there an adjustment to the air pump or is it bad?
Things could just be stuck (if your lucky ) from sitting. Make sure all tank drain valves are closed. Ck supply side to your air compressor for blockage(not very likely) Broken lines---leaking fittings---brake diaphragms..combinations of all or compressor. If you ave a portable compressor see if your system will hold air otherwise. sitting is often worse enemy. Bob
add stuck Governor to that. maybe a slight tap with hammer would loosen it up.
Ronnie: up top search line put in not building air pressure and hit search. Mike refers to governer also. Bob
Stuck governor on the compressor or the AD2 air dryer on the drivers side in the engine compartment needs servicing disconnect the 1/4 inch tubing on the bottom of the dryer it should start pumping.
That model of Eagle has DD3 brakes it will take over a 100 lbs to release the parking brakes if you are lucky, you may have a job on your hands lol
good luck
Hope it ends up simple. Happy bussin! Clifford(luvrbus) is the Eagle guy!
thanks for the advice, I'll try everything tommorrow
You are leaking air.
Period.
There are all sorts of valves in the system to explain why you get to 67 lbs and can't find the leak when you shut off the engine. That comes later.
You will need a set of maintenance manuals for the coach, start looking online now.
You will benefit from a decent oil-filled compressor as an accessory for the coach, get it now to help you find leaks without the roar of the engine drowning them out.
Get a spray bottle and some dish soap and make up some soapy water to spray around. When you find the leaks, you will need to replace the offending components.
Check the exhausts on all valves that have them. Check the lines and hoses.
Once you can get it to go to 120 lbs or so, and stop there and sit for awhile, then we can move on to the next challenge.
happy coaching!
buswarrior
our old eagle did that occasionally, then when least needed a problem, it would not build over 70 lb. turned out to be the govenor, $22.00 for a new one, that anyone can replace and it was fine to go.
I agree that if the compressor is pumping, you have an air leak. Clifford's advice will verify that. I also agree a good a good shop air compressor along with manuals specific to your coach should go in your tool box.
That said, in addition to other suggestions, something to look at is the discharge line and fittings on the bus air compressor to the drier and the wet tank. If you have an air leak between the compressor discharge and check valve you won't find it building air pressure in your system with an external air source. This can be done with the engine running. Spray soapy water on the discharge line to make sure it isn't leaking through the jacket.
Make sure the windshield wipers aren't turned on too.
Keep in mind it is a process and it may be more than one leak and just because you found one doesn't mean that there aren't more.
Clifford means that you need to make a 100+ psig brake application with the foot valve, after you push in the dash valve, to release the parking brakes on a DD3 system which is what your coach is equipped with.
Good luck and have fun.
Larry
I have a big compressor I can plug into the generator, can I plug into the air port behind the front bumper. I have'nt looked at the port yey, does it have a quick connect or do you have to use bushings to get the right connection. Can I run the portable compressor on the front port at the same time the engine is running the coach pump to hopefully make enough air to get the coach home, have about 10 miles to get home.
Where you at??? could be a busnut close by to help. Bob
Could have a quick connect but most have a plug from the factory where you can screw a quick coupling into and you can run the portable with the engine running won't hurt a thing
Check the pressure with the portable without the engine running if it airs it up to 120 lbs you have minor problems and not many leaks
good luck
Can't answer to fittings on the port but I doubt you will find a QD fitting and if there is one it will be one that won't fit anything you have. That's my luck.
I know a guy that drive his Eaggel from Colorado, to Michigan, all around Wisconsin and back to New Mexico on the oiless pancake compressor bought at a big box home improvement center. It was run off the inverter/gen set for the duration. (I'm not recommending this)
You should be able to get 10 miles to home to work on it before you go anywhere else. Make sure that it builds to 120 psig and maintains pressure there.
Test the brakes by making a brake application and make sure that you don't have any ruptured/dry rotted brake diaphragms. It will be a gross air leak and a big drop in air pressure. If they release and no leaking diaphragms, drive slow and all the disclaimer stuff so you can't say...but they told me it was OK...
I think you are on the right track to get it in to friendly territory to work on as long as you have and maintain 90+ air pressure you should have brakes
Good luck and no I'm not the guy that made the trip. It was a leak on the fitting to the inlet of the air drier and it took multiple governors and compressor change outs to get to that end.
Congratulations on your purchase
Larry
hi Bob, I missed your post about my location, Crestview, florida
lots of bus nuts in Florida.. I winter in Silver Springs Good luck. If you modify your profile put you location and you will find guys close to you that will like to help. Bob
Several nuts in your area: Destin Ft Walton Beach.
are you revving up to 1000rpms. mine just sort of sits when i'm idling (@500rpms), at about 70lbs. finally, it will start filling the front tank, then both will go up normally. Seems to have a bump at 70psi at idle. rev it up a little and everything goes up fine the rest of the way.
On my bus the gauge reads the pressure in the dry tank - the main brake tank. There is a pressure protection valve set at around 65 psi between the dry tank and all the rest of the air system. When filling from scratch, the pressure builds up to 65 psi or so fairly quickly, since only the wet tank and the dry tank are getting filled at that point. Then, when the pressure protection valve opens, the rest of the air system starts to fill. It is quite a large volume - the emergency tank, the accessory tank and the whole air suspension system - and it must fill to 65 psi before the gauge starts to move again, and at idle that can indeed seem to take forever. On my bug, again, the fast idle system is part of the accessory system and it won't bring the bus on to fast idle until the accessory system has around 70 psi in it. If the original poster's bus gets up to 70 psi OK, then can't get over than, suspect a leak in the suspension or accessory or emergency systems.
Brian
Quote from: bevans6 on December 04, 2011, 05:54:43 AM(snip) If the original poster's bus gets up to 70 psi OK, then can't get over than, suspect a leak in the suspension or accessory or emergency systems.
Brian
Yeah, that's about right - failure to air up past the protection valve setting is a pretty obvious clue. For what it's worth, I had to entirely redo my brake system -- everything from the governor (remote) to the S-cams is new. I have a wet tank, two brake tanks (all these are plumbed "direct" except for one-way valves) and an accessory tank. The accessory tank has a 70 PSI protection valve. My system airs up to ~ 115 in a little over a minute; I can hear the protection valve open when the main tank gauge reads 70 but it doesn't appear that the filling rate slows down much at that point. I have rigged up a gauge for each tank, to get the system going, I had to use a couple of old gauges temporarily until I can get new ones. I can hear a tiny air leak in two of the old gauges but if I air up to 120 pounds, it only falls 7-8 psi in an hour. So, there must not be any substantial air leaks.
Eagles have 5 tanks they will hang around 70 lbs till the 2 front tanks fill White Eagle has it figured out no jello bags on the suspension to fill he can go from tank to tank and see if they are filling or has a valve stuck each tank has a automatic air drain if one leaks the air stops there if one is leaking unscrew it plug it or install a manual type drain and fwiw they will not pressure up till all 5 are full
good luck