Ok - it happened again, and our theory yesterday is wrong - it is not the high pressure safety valve.
Slowing down at an intersection just after leaving camp this morning, there was a pop, and now I know that the noise was our air brakes popping and engaging (simultaneous with the air warning alarm going off).
The pressure had dropped instantly to 30psi again. I got safely off the road, and unlike yesterday - this time the air pressure did not climb back to 110psi on its own.
Revving the engine to 1500rpm, I can barely get the air pressure back up to 55psi. If I drop to idle, the pressure drops down to 30psi.
Walking around the coach - the governor on the air compressor may be the issue. It is leaking air, and continues after the engine stops. There are three plug holes on the back of the governor. The bottom is not plugged, and has air coming out. This was also open yesterday - I have no idea if it supposed to be this way, or whether the plug fell out.
Anyway - we now can't build up pressure to drive, and are on the road right outside Monument Valley. We had made an appointment at the diesel garage in Durango this afternoon, but now are about to call in Coach Net.
Any help appreciated - call 408-667-9022.
- Chris
Some more observations...
When I first put the new air compressor air filter on, I was impressed with how much quicker our bus aired up. But yesterday morning, the bus aired up slowly - it stuck at 30psi for a while, until I put the bus in fast idle. Once it got to 110psi, it was fine and held pressure.
Today - the same thing happened - the bus sat at 30psi for a long while until I gave it a lot of throttle to air it up.
I am certain this is related to the failure we've experienced the past two days.
I am thinking the governor's over-pressure relief valve may be sticking open. Yesterday it popped back shut. Today it isn't.
I am going to saturate the governor with WD-40, and try to find the manual to figure this one out.
But if you have ideas - please call. Thanks!
- Chris
Hey Chris,
Are you sure that the governor is your only leak? When you say air brakes popping and engaging I'm wondering if one of your air brake cans is bad? I'm around this morning so give a call if I can be of help. I'm looking for my governor manual now....
Steve
Chris, don't you have a governor on the spare compressor that is in the bay the port that is leaking is the exhaust port it is open no plug
good luck
We just checked that actually, Clifford - there is no governor on the spare compressor. (Good memory!!)
- Cherie
Ok.. lubbed up the exhaust port on the governor, did a little percussive maintenance... turned the engine on. And she's airing up normally, and no more whooshing of air out the governor.
*crossing fingers*
- Cherie
everything you ever wanted to know about a D2 governor (D2A is just non-adjustable D2)
http://www.bendixvrc.com/itemDisplay.asp?documentID=5644 (http://www.bendixvrc.com/itemDisplay.asp?documentID=5644)
The only time air is supposed to come out the exhaust port is when the governor is transitioning to cut-in, when it has to dump the air in the unloader port to let the compressor start to compress again. If it is dumping air continually, then it is broken. Probably the inlet/exhaust valve has some junk in it, or an o-ring has cracked.
I would get a new one, it's about the most common air thing that you can possibly ask for at a store. If it's a D2, that is.
Brian
The D2A is adjustable Brian you do it with shims they can be set to cut in at 5 lbs below max pressure used in construction equipment where there is not much tolerance for air pressure drop on the air controls,I ran one on my bus for years because I didn't like the cut in pressure for the D2 mine was set on 125 cut in was 117
good luck
Just as a side note, how often should I replace my governor? Seems like a read a lot of posts where these go out!
TM
Tm, those are supposed to be part of the pm if you service the D2 they don't give problems most neglected item on the air system so they go south,only cost you a 1.25 and 15 minutes of time but people wait till they quit on the road lol
good luck
Luvrbus,
I read the D2 service manual and it sounds like the PM consists of testing the unit for proper operation and checking for leaks. Is there anything else you do? Would you replace this unit on a time schedule or wait until it fails a test?
Thanks
TM
You should carry one in the bay. Cost me $12/15 at NAPA>
TM, they will show when they are going bad just like Bendix's SD-01-16 says, me I cleaned mine 1 time a year and replaced the o-rings 1.25 is abetter to me than 15 or 20 bucks and looking for one knock on wood never had a failure or replaced a D2A like you read here Bendix has to love these guys here lol
good luck
coach net will pay for a service call. You are responsible for labor and materials @ around $125 + or -
Don & Sheila
Rather than opting for a service call I'd have coach net tow it to the shop they already had an appointment at for service.
Other wise they could be paying a service guy to "chase" parts all day time and mileage.
Just my way.
;D BK ;D
Percussive maintenance worked, and got us to Durango. Just spent the afternoon at Vandegrift Diesel. They were absolutely awesome, and seemed delighted to work on a bus.
We had them adjust the brakes, replace all the drain valves, Lubed anything with a zirk and got a new governor to put on later.
- Cherie
Did you watch them do the brake adjust? The next time its yours to do. Then you can show someone else. Remember - See one, do one, teach one.
How about the greasing? Did you watch and learn?
Nice job figuring out the governor. There is a rule about hammers - if a bigger hammer doesn't fix the problem then the part needed replacing anyway, ;D
Good luck and thanks for the after action report.
Bill
Oh yes, we did :). They let us play in the pit with them and taught is as they went - so much fun, and educational. Very much looking forward to the preventative maintenance workshop at the Choo-Choo rally, and getting confident with all this stuff.
I'm loving grease and oil on my clothes. Besides, oil is a nail color, right?? :).
- Cherie
One of my grandfather's favorite expressions was "give it a hit with a hammer."
Right on guys, glad to see that you got rolling again. I am making a note of that shop, always good to know of a place that wants to work on an antique! Oh, and put that new governor on and rebuild the old one! That is what I am going to do with mine.
Safe travels,
Steve
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Your Welcome.... :( :o :( :o :( :o :( :-*
PS. Rude is not acknowledging an apology.
Sorry now i did that too.
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Quote from: technomadia on September 30, 2011, 05:56:21 PM
and got us to Durango. Just spent the afternoon at Vandegrift Diesel. They were absolutely awesome, and seemed delighted to work on a bus.
Oh yes, we did :). They let us play in the pit with them and taught is as they went - so much fun, and educational. Very much looking forward to the preventative maintenance workshop at the Choo-Choo rally, and getting confident with all this stuff.
I'm loving grease and oil on my clothes. Besides, oil is a nail color, right?? :).
- Cherie
??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ???
Sorry eagle, had a lot going on and very limited bandwidth in which to do it. We are seriously behind on a lot of stuff as a result.
Quote from: technomadia on September 30, 2011, 07:24:15 PM
Sorry eagle, had a lot going on and very limited bandwidth in which to do it. We are seriously behind on a lot of stuff as a result.
Got your message.
In all seriousness,earnestly and sincerely GOOD LUCK and BEST WISHES.
On the Road,gypsy,vagabond and human since 2004
donald and Deborah