Community Forums

Rexhall97 · 11-18-2022, 06:27 PM

1997 Aerbus 3650xl on P30 chassis with Chevy 454

1. Control panel not working. Water pump and other switches work fine, fuse tested good. Ideas on where to start? Hard to know tank levels or battery charge.

2. How can I determine if the house batteries are getting a charge?

3. New engine battery discharges in only a few hours when vehicle is off. Disconnect switch clicks something , but light stays illuminated and battery drains.

4. Anyone know what size, voltage and AH coach batteries are correct for this coach?

Thanks to anyone that can help

Ed in NE PA

MrMark52 · 11-19-2022, 09:02 AM

1. On your control panel - Start looking for a bad ground.

2. To determine if the house batteries are getting charged from the convertor - with the coach electrical tether disconnected, put a DC voltmeter on one of the batteries and get a reading.
Then plug the tether in. You should see the voltage jump up.
FWIW - your coach may or may not have a BIRD system that allows chassis battery charging when the coach batteries are fully charged.

3. Typically the coach and chassis 12VDC circuits are separate, or at least have very little crossover. That said - your chassis battery could be something as simple as the dash radio being on but not turned up.
If your voltmeter can read DC current then put it in series with either the battery ground or hot, to see how much current is being drawn - from that you might get a clue of where to look. But whatever it is that’s consuming the power should only be chassis related.
Some users will install a knife switch on their chassis battery.
If the disconnect switch your speaking of is the coach battery isolation panel (usually by the entry door), that light is powered by the coach batteries. The click your hearing is probably the battery isolation relay/solenoid in the BCC (battery control center). It’s typically a device that is powered open or closed when you hit that switch, and once powered, it is mechanically latched in the open or closed position.

4. Depending on your coach builder you’ll typically have room for 2 or 4 Group 27 batteries, when I replace coach batteries, I typically only use AGM’s. Last ones I replaced were Duracell 27M’s 100 aH

5 - FWIW - a coach as old as yours, the original convertor will eat your batteries. You need to upgrade it to a microcontroller, 4 stage charging design. Progressive Dynamics makes a drop in replacement for what you have.

Rexhall97 · 11-19-2022, 09:15 AM

Great information and thank you. Coach is in for ebrake repair and when I get it back I'll do some of the things you suggested. The battery disconnect switch is located inside the door and has buttons for the coach and engine battery. The coach disconnect works fine. The engine button clicks the relay but it stays on/connected. I have to manually disconnect the engine battery under the hood. The converter you mentioned, will it be plug and play, or will I have to figure out wiring. I'll start googling progressive dynamics to see what I can find. Thank you again for the reply, I'll keep you updated once I get my old bus back lol

MrMark52 · 11-19-2022, 09:46 AM

Quote:

Originally Posted by Rexhall97

Great information and thank you. Coach is in for ebrake repair and when I get it back I'll do some of the things you suggested. The battery disconnect switch is located inside the door and has buttons for the coach and engine battery. The coach disconnect works fine. The engine button clicks the relay but it stays on/connected. I have to manually disconnect the engine battery under the hood. The converter you mentioned, will it be plug and play, or will I have to figure out wiring. I'll start googling progressive dynamics to see what I can find. Thank you again for the reply, I'll keep you updated once I get my old bus back lol

The PD convertor (and there are others, but PD is probably best) is Plug’n’Play. Just match the model number of what you have to their replacement chart.
I’ve found the best pricing, delivered, through Amazon.

Your chassis battery issue for the light staying on and it appearing the that the disconnect isn’t disconnecting typically means the relay/solenoid needs to be replaced (it has welded itself together internally).

If you don’t know the service history of the coach - replace the rubber brake lines and then do a complete brake system flush and bleed.

If you have the Independent Front Suspension - make sure the bell cranks have been replaced. My driver side was worn out at just 17k miles (actual miles! - the coach hadn’t been driven much in 27 years when we got her).
I replaced the pitman arm and all the tie rod ends at the same time (ball joints were all good).

This book will be your friend - https://www.irv2.com/forums/downloads.php?do=file&id=68

Replace the shocks if the ones on the coach are over 5 years old.

I’ve got more recommendations if you want them.

Oh, and if your coach has AutoPark on it, then go to the Files|Chassis section (above) and find the AutoPark thread and downloads.

Rexhall97 · 11-20-2022, 07:12 AM

Gladly accept any/all input, thank you. I have the hard copy of the book you referenced which is great. I see auto park indicator on dash, I will look for the threads you mentioned next. Hope to have the old bus back from the shop soon.

MrMark52 · 11-20-2022, 08:01 AM

Quote:

Originally Posted by Rexhall97

Gladly accept any/all input, thank you. I have the hard copy of the book you referenced which is great. I see auto park indicator on dash, I will look for the threads you mentioned next. Hope to have the old bus back from the shop soon.

Well, if for sure you do have AutoPark - here is where you should probably start - Oemy's Web Site - J71 Autopark .

I don’t think I have AutoPark on our current W22 chassis, and 99% sure it wasn’t on our ‘91 P30 chassis as the emergency brake was lever/cable driven.

As one of the posts I’ve read about AutoPark - it’s not a matter of if, but when, it fails. Good to read up on it so should it fail on you going down the road that you know what to do.

Thanks to Oem’y and oldusedbear for their contributions!

As for other things on your chassis - and I may have mentioned before - replace all your coolant/radiator hoses, including the little crooked hose between the intake manifold and water pump.
I found that due to improper care that the radiator had sprung a leak where the core attached to the end caps. I wasn’t happy with what I was finding for a replacement - so I pulled the radiator and took to a radiator shop that had been around since the late 40’s. They recored the radiator using the old end caps - and add an additional row to improve cooling performance. There was plenty of room to thicken the core and doing so didn’t pose any clearance issues when reinstalling back into the chassis. Cost was about what a new radiator would have been, but quality of the end product was superior to what they sell new today.

We put 10k miles on our coach in 2 years. It was our first foray into the cult, and we quickly found we didn’t have enough room.
But being 27 years old, I did a lot of work to her - rebuilding the brakes, replacing rubber hoses, upgrading electronics for anything related to coach comfort and convenience (TV’s, generator, furnace, water heater, etc.).

Let me know if you need help - will be glad to share my thoughts.

Rexhall97 · 11-22-2022, 06:03 PM

Thank you for all the advice. I’ll start working on it this weekend

garry1p · 11-22-2022, 06:25 PM

This is a site that has lots of information that you will find helpful as you go forward.

https://bryantrv.com/docs.html

George Schweikle · 11-23-2022, 07:00 AM

The stock autopark switches are known to fail. Brazel's has this upgrade that I used on a previous motorhome with autopark;
https://www.brazelsrv.com/US21-Ultra...ch-Upgrade-Kit

Quote:

Originally Posted by Rexhall97

Gladly accept any/all input, thank you. I have the hard copy of the book you referenced which is great. I see auto park indicator on dash, I will look for the threads you mentioned next. Hope to have the old bus back from the shop soon.