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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Paladin on August 31, 2010, 03:17:35 PM

Title: My singing bus!
Post by: Paladin on August 31, 2010, 03:17:35 PM
I have a question. I ran by bus today and noticed that it sings more in the air lines today. Is this just thermally related?
Do others have a bus that sings for a while after shut down? Should we form a group and go on tour?

-Dave
Title: Re: My singing bus!
Post by: robertglines1 on August 31, 2010, 03:26:34 PM
does your bus air stay up when shut off?sounds like a leak around a ck valve or another pressure regulating device...front or rear? tank drain?  BOB
Title: Re: My singing bus!
Post by: fe2_o3 on August 31, 2010, 03:31:45 PM
What key does it sing in?  Mine is between E and F...Cable
                          Equalizing? Ping?
Title: Re: My singing bus!
Post by: Paladin on August 31, 2010, 03:35:05 PM
Quote from: robertglines1 on August 31, 2010, 03:26:34 PM
does your bus air stay up when shut off?sounds like a leak around a ck valve or another pressure regulating device...front or rear? tank drain?  BOB


It doesn't stay up forever but it usually stays up for a day or so slowly losing. The 'singing' is the air lines running fore to aft. I'm just not sure what causes it besides temp or maybe humidity.

-Dave
Title: Re: My singing bus!
Post by: steve wardwell on August 31, 2010, 03:59:34 PM
Is she off key? If she is , squeeze her tires.
Title: Re: My singing bus!
Post by: robertglines1 on August 31, 2010, 04:12:32 PM
my 78 had a air dryer in system does yours?if so does it sound off?purge..moisture in system can cause problems,corrosion,sticky valves and relays and ck valves. had a ck valve on a air tank sing...prob low C..replaced all is quiet now..
Title: Re: My singing bus!
Post by: FloridaCliff on August 31, 2010, 05:35:45 PM
If you have a brake diaphragm with a slow leak,
it could make a singing sound through the brake relay valves exhaust port.

Cliff
Title: Re: My singing bus!
Post by: Paladin on August 31, 2010, 06:44:31 PM
You guys are scaring me. It sounds like and feels like the copper lines running under the chase making sounds but now I'm more worried.
Title: Re: My singing bus!
Post by: RickB on August 31, 2010, 07:06:52 PM
If she starts demanding double scale and her own dressing room that's when you need to get scared.

Send her to a vocal coach that'll fix her
Title: Re: My singing bus!
Post by: JackConrad on September 01, 2010, 05:04:06 AM
I think you are hearing air moving through an air line. Once the system is full, if air is moving it has to be getting out somewhere. We hear that type of sound on startup as the system fills. I think it is caused by the air flowing through the check valves (valve flutter). I think our coach sings in the key of L. At least a friend said it sounded like L?   Jack
Title: Re: My singing bus!
Post by: gumpy on September 01, 2010, 05:58:34 AM
Yes, it's air moving through a valve. You have a leak somewhere. I get that when I attach shop air to mine. It's caused by the air moving from the shop air into the bus system to
replenish the air that is leaking out. I have two or three small leaks I know about (blower belt tensioner, radiator shutter filter), and some I don't (aux system)
It's a never ending battle to get all the leaks fixed.