Missing air tank - 4108a

richard5933 · November 02, 2017, 03:36:05 PM

I'm working my way through getting familiar with my new 1974 4108a, and right now I'm stumped. I can't find one of the air tanks mentioned in the Operator's Manual (pg 58).

PRIMARY RESERVOIR

Primary reservoir is mounted horizontally on front axle rear bulkhead. Drain valve is located
just behind the left-front tire just above and on the same side if the bulkhead as the front axle splash
apron. Drain valve is closed with handle parallel to valve body and open when handle is at right angle to valve body.

The manual lists the Main Reservoir (wet & dry sides), Primary Reservoir, Secondary Reservoir, and the Parking Brake Reservoir. I have found all the tanks and drain valves except for the Primary.

Anyone have a clue what the manual is talking about and where this tank & drain valve are located? Maybe someone with one of the variants of this model will be able to confirm whether or not the manual is correct. I'm starting to wonder if a change was made in the design that is not reflected in this manual.

chessie4905 · November 02, 2017, 04:14:35 PM

My 4905 has: one under driver in compartment, two above batteries in compartment right behind passenger front wheel and one on bulkhead rear of rear axle mounted vertically with several of the brake system valves mounted next to it. It has a drain valve on bottom.

richard5933 · November 02, 2017, 04:33:01 PM

Quote from: chessie4905 on November 02, 2017, 04:14:35 PM
My 4905 has: one under driver in compartment, two above batteries in compartment right behind passenger front wheel and one on bulkhead rear of rear axle mounted vertically with several of the brake system valves mounted next to it. It has a drain valve on bottom.

Thanks

Those all I have. Even was able to get them drained. There is the one additional tank listed in the manual that I can't find. Curious if your Operator's Manual also shows the tank on the front axle bulkhead? Maybe they changed things in production but kept using the same manual?

buswarrior · November 02, 2017, 04:42:05 PM

Date of the manual pages?

The world changed a lot in 1975 for air systems...

happy coaching!
buswarrior

chessie4905 · November 02, 2017, 05:02:00 PM

Unfortunately I'm in hospital right now with a knee replacement, so I can't check my manuals till I get out of here tomorrow or Saturday, but I'll check when I get home. Some of the change they did in those years were dual brake system and antilock systems. Also they had Special equipment options, referred to in manuals breifly and also in my wiring diagrams. They all had hub piloted wheel option. Believe it or not, you can convert if desired to the correct studs and wheels. The hub diameter is the same; convert the mms to inches, they're the same.
Coach net manuals list CDs for the early and late models produced, but have same part number. Also check out one that lists parts needed to convert to a V730, Sheppard power steering, in 4106's and 4104's, etc.

richard5933 · November 02, 2017, 05:10:25 PM

Quote from: buswarrior on November 02, 2017, 04:42:05 PM
Date of the manual pages?

The world changed a lot in 1975 for air systems...

happy coaching!
buswarrior

No idea. There is not a date on the Operator's Manual. It was not in the bus when I got it, so I ordered it online from Coachinfo.com

Perhaps my '74 model and the manual are not the same?

buswarrior · November 02, 2017, 06:09:49 PM

A world of difference in the air system plumbing between a 1974 and a 1976, and a fine scalpel needs to be used in the transition over the top of 1975.

A few GM's also got optioned with DD3 brakes, just to screw things up further...

Got to have the right pages for the right bus.

happy coaching!
buswarrior

Scott & Heather · November 02, 2017, 07:34:38 PM

Richard, I wish I knew something about your bus but I don't. So I'm here just to say I'm impressed with how fast you're getting back into this after such a recent scare. You have my respect sir. Carry on. Hope to meet you someday.

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richard5933 · November 03, 2017, 02:02:38 AM

Quote from: Scott & Heather on November 02, 2017, 07:34:38 PM
Richard, I wish I knew something about your bus but I don't. So I'm here just to say I'm impressed with how fast you're getting back into this after such a recent scare. You have my respect sir. Carry on. Hope to meet you someday.

Sent from my iPhone using Tapatalk Pro

Thanks! If your travels ever bring you through SE Wisconsin, you've always got a place to park and plug in here.