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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: richardkillmon on June 23, 2020, 04:34:37 PM

Title: rebuild air compressor while still on engine
Post by: richardkillmon on June 23, 2020, 04:34:37 PM
Hello,

Has anyone rebuilt their air compressor while the bottom piston half is still on engine?
I have disconnected all air lines and put a gauge directly on the compressor - no reading - zero.
I can't go through the top/floor to remove the unit. I don't want to remove engine yet.

MCI 5B 1976 8V71 Detroit.
any help?

Thanks

Rick
Title: Re: rebuild air compressor while still on engine
Post by: luvrbus on June 23, 2020, 04:56:49 PM
It will need to be removed because it could be a key on the compressor drive striped or the drive it's self could be striped 
Title: Re: rebuild air compressor while still on engine
Post by: richardkillmon on June 23, 2020, 05:02:19 PM
thanks
what are the chances that is a simple fix?

Thanks

Rick
Title: Re: rebuild air compressor while still on engine
Post by: luvrbus on June 23, 2020, 05:05:19 PM
It is simple with compressor off if the key sheered  but there is usually a reason one sheers ,I feel for you removing that compressor not a easy task but doable
Title: Re: rebuild air compressor while still on engine
Post by: Raymond smith on June 23, 2020, 06:34:51 PM
If it is like mine on my 6-71 the finer drive hub let go where the steel keyway attaches to the hub. It wouldn't pump nothing. Replaced with an all steel hub. Easy job on a 4104. Raymond
Title: Re: rebuild air compressor while still on engine
Post by: Raymond smith on June 23, 2020, 06:36:01 PM
Fiber drive hub
Title: Re: rebuild air compressor while still on engine
Post by: Dave5Cs on June 23, 2020, 07:02:54 PM
Luke told me that they move the engine out 6 to 8 inches to get it out on the 5's
Title: Re: rebuild air compressor while still on engine
Post by: luvrbus on June 23, 2020, 08:46:50 PM
Quote from: Dave5Cs on June 23, 2020, 07:02:54 PM
Luke told me that they move the engine out 6 to 8 inches to get it out on the 5's

I removed mine from my 5B without moving the engine it wasn't to bad. going back in was a bitch,the compressor needs to be removed and the drive checked even the steel drive coupling can strip
Title: Re: rebuild air compressor while still on engine
Post by: Dave5Cs on June 24, 2020, 12:42:05 PM
Maybe but thats what he told me. I know my 5C has a 1/2" between the compressor and the bulk head and I don't fit in the side rear door and from the top in the bedroom is 8x 8" hole and have used it before but not to comfortable LOL. ;)
Title: Re: rebuild air compressor while still on engine
Post by: luvrbus on June 24, 2020, 01:29:10 PM
If it has bolts, not nuts and studs it will come out in that tiny space, removing 1 stud took me 3 hours lol a bolt went back in the studs place just in case I had to do it again
Title: Re: rebuild air compressor while still on engine
Post by: Gary Hatt - Publisher BCM on June 24, 2020, 01:31:21 PM
If you decide to do that, it is recommended that you shut down the engine during this process.  ;D
Title: Re: rebuild air compressor while still on engine
Post by: freds on June 24, 2020, 08:31:16 PM
Quote from: Gary Hatt - Publisher BCM on June 24, 2020, 01:31:21 PM
If you decide to do that, it is recommended that you shut down the engine during this process.  ;D

Are your comparing the motorcycle mechanic with the heart surgeon?
Title: Re: rebuild air compressor while still on engine
Post by: TomC on June 25, 2020, 10:24:32 AM
My air compressor stopped working because the fiber gear failed. I had it rebuilt with steel gear. I know that if it fails it will take out the gear drive-but how often does an air compressor fail? Good Luck, TomC
Title: Re: rebuild air compressor while still on engine
Post by: luvrbus on June 25, 2020, 12:17:18 PM
When a air compressor fails with the steel drive it shears the key on the compressor, the fiber drive was a good idea if it failed the chunks went through the gear train without damaging the gears only problem was they failed a lot