rebuild air compressor while still on engine

richardkillmon · 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

luvrbus · 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

richardkillmon · June 23, 2020, 05:02:19 PM

thanks
what are the chances that is a simple fix?

Thanks

Rick

luvrbus · 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

Raymond smith · 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

Raymond smith · June 23, 2020, 06:36:01 PM

Fiber drive hub

Dave5Cs · 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

luvrbus · 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

Dave5Cs · 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.

luvrbus · 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

Gary Hatt - Publisher BCM · 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.

freds · 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.

Are your comparing the motorcycle mechanic with the heart surgeon?

TomC · 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

luvrbus · 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