Author Topic: Closing off A/C Air Valve (SOLVED)  (Read 2572 times)

Offline GnarlyBus

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Closing off A/C Air Valve (SOLVED)
« on: March 12, 2018, 12:52:23 PM »
I removed the OTR A/C Compressor from the engine compartment and now there's a slow leak on the pressure  valve that was feeding it. It tried to close the loop with the original hose but now I'm thinking I need to close this valve off completely from the air system and be done with it. What's the best way? Is there a way to close this valve completely without removing it?
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline gumpy

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Re: Closing off A/C Air Valve
« Reply #1 on: March 12, 2018, 01:08:39 PM »
Remove the supply line and plug it. Problem solved.
Craig Shepard
Located in Minnesquito

http://bus.gumpydog.com - "Some Assembly Required"

Offline GnarlyBus

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Re: Re: Closing off A/C Air Valve
« Reply #2 on: March 12, 2018, 01:43:43 PM »
Remove the supply line and plug it. Problem solved.
Thanks, when you say plug it do you mean with a brass fitting of some sort or some type of rubber plug?

These questions feel kinda dumb but I've never messed with the air system before. I want to do it right the first time.
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline Jim Eh.

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Re: Closing off A/C Air Valve
« Reply #3 on: March 12, 2018, 06:50:52 PM »
Brass or steel fitting. Depending on where you plug it you will need either a pipe thread plug (or cap) or an SAE (has an angled contact area) threaded plug (or cap). Just be careful when you undo ANY air fitting. Always assume the gun is loaded. Safety glasses are a good idea. Contaminants in an air system can turn into projectiles. If you can let the bus sit for a couple of days the air system will probably drain down. Just undo fittings slowly.
"Some days it's just not worth chewing through the restraints"
Jim Eh.
1996 MC12
6V92TA / HT741D
Winnipeg, MB.

Offline bevans6

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Re: Closing off A/C Air Valve
« Reply #4 on: March 13, 2018, 07:58:06 AM »
I think (I removed this stuff from my bus many years ago) the hard line going to the twist handle valve is the feed line.  If you trace that hard line it will go back to an air manifold (a little hex shaped block with several lines connected to it) mounted on the rear wall of the engine bay.  If you take the hard line off at that manifold and remove the adaptor that screws into the manifold itself, you can replace that adaptor with a 1/4 NPT plug, and some teflon tape or paste.  You can then remove that whole setup from the engine bay and toss it (or save it, the same pieces are used for the fan belt tensioning system so you would have spares).
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

Offline GnarlyBus

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Re: Closing off A/C Air Valve
« Reply #5 on: March 13, 2018, 12:40:56 PM »
Thanks everybody! This is just what I needed! Found the manifold and capped this line there. One small leak down who knows how many to go?!
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

Offline buswarrior

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Re: Closing off A/C Air Valve (SOLVED)
« Reply #6 on: March 13, 2018, 01:41:15 PM »
It is nice when we get to see the conclusion of these posts.

And that the original poster contributes something back to the collective knowledge.

You can stay.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline GnarlyBus

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Re: Closing off A/C Air Valve (SOLVED)
« Reply #7 on: March 13, 2018, 01:57:42 PM »
Thanks I try to finish my threads. I hate reading old threads where someone posts a problem like "bus broke down, please help" and then people suggest all these great diagnostic options and the OP is never heard from again!

I've got a Jake brake thread I'm itching to call solved after all I've done to fix them and share exactly what was wrong but I've got to road test them first!

Thanks for letting me stay! ☺
1984 MC-9 w/ 6v92TA & Allison 740
Oregon Summers & Arizona Winters
Full-Time since 2015

 

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