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Air Systems questions

i found 3 air tanks on my coach. One is a slender cylinder located just behind the Gen box. The other two are less cylindrical and a bit further back. i believe they are for brakes. what is front tank for? What is best process to track and locate leaks. Are there places that are common and typically leak that should be checked first. Where is the six pack located? What is max air pressure I can put into system? Any help or suggestions are much appreciated
2001 4010 U320
Build 5875

Re: Air Systems questions

Reply #1 –
Small tank is for slide bladders.

There is a lot of previous discussion about tracking down air leaks, how to rebuild six packs. etc.
Recommend you try hovering over "Community", click "search" and put in search terms.  There is a ton of useful information on the forum and Search makes it relatively easy to find.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Air Systems questions

Reply #2 –
Quote from: Spiderhitch –
What is max air pressure I can put into system?
Your engine air compressor should cut out (stop pumping air) at around 120-130 psi.  This then is your normal maximum system air pressure.  The exact cut out pressure is determined by the D2 governor.  See link below explaining how the D2 works.

Your air system will have a safety relief valve on the wet tank that should open at about 150psi.  Try to avoid having this happen.

Air Governor [ForeForums Foretravel Motorcoach Wiki]

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Air Systems questions

Reply #3 –
Spider, you are correct, the aft 2 tanks are the brake tanks, right:rear and left:front.

In a 2001 40' slide room coach: the forward (thin) tank is the HWH tank.  It only supplies air to the slide seal manifold to inflate or deflate the seal, and should only be pressurized by the 12v aux air pump. The front 6-pack hides above that HWH tank and the tank must be removed to access the pack.  4 bolts and two air lines and the tank drops out. The rear 6-pack is mounted above and forward of the differential.  Several good threads in the forum on how to rebuild 'em.

Chasing air leaks has become my most favorite pastime.  Always use safety "blocks" when under the coach and a bottle of "Snoop" leak detector is a must have, however, there are 6 check valves in a 2001 air system, and they can leak and never blow bubbles.  I'm in the process now of replacing every check valve in the system.

Whenever I find the last leak in my coach, that'll be the day that politicians start telling the truth.  Woody.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold