| Author | Message | ||
| Prather Ellsberry (Prather)
Registered Member Username: Prather Post Number: 1 Registered: 10-2006 Posted From: 207.69.137.207 Rating: N/A |
Bus air started cycling between 120 & 114 lbs, changed governer, same problem. I have a AD 2 air dryer, thinking now this may be the problem. Has anyone had this problem and what was the fix. Thanks in advance for any help. Prather | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 935 Registered: 12-2000 Posted From: 65.92.191.246 Rating: N/A |
Hello Prather. The cut-in and cut-out points are determined by the air compressor governor. The air dryer does as it is told by the governor. Unusual that a new governor is not showing you somewhere 20 to 25 lbs between cut-in and cut-out. Who else has an idea? happy coaching! buswarrior | ||
| Chuck Lott (Chuckmc8)
Registered Member Username: Chuckmc8 Post Number: 186 Registered: 5-2004 Posted From: 72.152.148.123 Rating: N/A |
Prather, go to the Bendix web site...WWW.Bendix.com, the contact info will have a toll free phone # to the bendix tech help line. Call them and tell the tech whats going on and what you've tried. Bet they can help. Always nice folks. HTH, Chuck | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 335 Registered: 10-2003 Posted From: 71.58.126.56 Rating: |
Make sure that the problem isn't a faulty gage before you spend a lot of time on the problem. Cycling..... do you mean cutting in and cutting out? Is it holding pressure when it hits 120 or is there an air leak causing it to drop right away? The 114 could be the gage sticking on it's way down and is actually getting down to 105 before kicking in. Try tapping the gage at 114 and see if it jumps down to 105. | ||
| Prather Ellsberry (Prather)
Registered Member Username: Prather Post Number: 2 Registered: 10-2006 Posted From: 207.69.139.9 Rating: N/A |
Called the Bendix Tech. He said two things to check were the inlet pressure to the governer, if that wasn't the problem to spray some WD 40 on the unloader valves located in the air supply to the compressor. Put a gage in line to the air supply to the govener, compressor was working as it should, unloading at 120 lbs started compressing again at 105 lbs. So I have a air leak somewhere. After shutting off engine and letting air decay off for about 20 minutes, still had 119 lbs on gage at dash and 0 lbs on gage at compressor. So I am searching for the air leak, my old ears makes it tough, can't hear it but know it is some where. Thanks for all the input. | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1095 Registered: 12-2000 Posted From: 67.181.163.170 Rating: N/A |
Prather - Got a fifth or sixth grade boy in the neighborhood? Grandson maybe? If so, see if they can hear the air leak and help you trace it. If not, time to break out the spray bottle with soapy water! FWIW & HTH. . .  | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 337 Registered: 10-2003 Posted From: 71.58.126.56 Rating: N/A |
Another option would be to use a mechanic's stethoscope with the metal tip and amplifier removed, listening through the hollow tube. Works for larger leaks that you can't hear. | ||
| Phil Smith (Phil_smith)
Registered Member Username: Phil_smith Post Number: 32 Registered: 3-2006 Posted From: 24.117.40.105 Rating: N/A |
I think it's the Dash gauge sticking or defective. Just another opinion from the peanut gallery ! Phil in Az. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 226 Registered: 11-2005 Posted From: 63.97.117.41 Rating: N/A |
Sometimes air gages get moist and rust at the inlet hole which is very small to start with. Happened to me. | ||
| Prather Ellsberry (Prather)
Registered Member Username: Prather Post Number: 3 Registered: 10-2006 Posted From: 207.69.137.202 Rating: N/A |
It was the AD-2 dryer, specifically the dryer outlet check valve was leaking. Prather | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 937 Registered: 12-2000 Posted From: 70.48.195.211 Rating: N/A |
Hello Prather. If the system reached cut-out, when the governor signals the air dryer to purge, the line from compressor to air dryer purges along with the volume inside the air drier. The line beyond the drier, towards the wet tank, should stay pressurized. If the compressor is still cut-in when you shut down, and the line leaks out the air drier purge valve, there is a problem with the purge valve. If the wet tank pressure drops over time when the compressor is cut-out, and the rest stays pressurized, the air drier valving is suspect. The AD2 is a fine drier, and rebuild parts are readily available. happy coaching! buswarrior | ||
| Prather Ellsberry (Prather)
Registered Member Username: Prather Post Number: 4 Registered: 10-2006 Posted From: 207.69.136.204 Rating: N/A |
Buswarrior I don't know about all that but when I discovered the check valve was leaking back into the Dryer I just got a rebuilt AD2 and everything works fine now. Prather | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 938 Registered: 12-2000 Posted From: 64.228.91.228 Rating: N/A |
That works! happy coaching! buswarrior |
