Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 09, 2025 ...

Update Isolator/Auxiliary Start Panel

February 13, 2025, 12:37:10 pm

This was how our panel started.

We decided to replace and renew a few things in ours, which is located on the far wall inside the engine compartment.

1)  Like many others have done, use an Orion DC/DC charger in place of the isolator. Using an Orion made sense for us because we have switched to Victron equipment and LiFepO4 on the house side. You can add specifications for the batteries you are charging with the Orion; these can be obtained from the battery manufacturer. In addition to Bluetooth, it supports VE.Direct communications, which allows you to control it and monitor the condition of the batteries.

Additionally, we were experiencing indications of low dashboard gauge voltage one day and normal the next, which was another reason for the replacement. After ruling out connections and the alternator, the next possibility was that perhaps  the Isolator was starting to malfunction and was preventing voltage from reaching the batteries.

2) Replace the boost solenoid; the connections on it were crusty, and it was beginning to resemble a geode after 25 years in the engine compartment environment.

3) Clean up the relays/breaker wiring. At some point this area had been modified by moving the voltage sense/remote start wiring from the A/C comp. breaker to a dedicated one. This new breaker and its wiring were just "hanging out.".

4) Replace the 90A fuse and remote start relay, just for good measure. This fuse feeds the dashboard power relay panel in front of the passenger seat; after 25 years in the engine compartment, it has done its job. The remote start relay worked,  but I had one in much better condition (from when I replaced the dual ignition solenoids with a single Blue Sea solenoid).

5) Clean up the mounting plate and the component mounting. It had a mixture of through bolts/nuts, rivnuts, and self-tapping screws. Additionally, the way it was secured to the rear wall caused a side to side bow in the plate.

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Re: Update Isolator/Auxiliary Start Panel

Reply #1 – February 13, 2025, 12:53:01 pm

Here is the updated panel all back in place.

As I was replacing most of the parts, I simply unmounted each component separately, leaving the wiring intact.. I then attached all of the new components to the cleaned plate and did what interconnect wiring I could. I did reuse, after cleaning the lugs, some of the existing cables. I reinstalled the plate and transferred wire by wire from the old components to the new ones. This was easier (for me) than labeling everything.  Due to the length of existing cabling, things could not move much, at least without extensive effort, so they went back in the original locations.. Of course the house and chassis batteries were disconnected!

We followed what @Tommy D  did and used his picture as a guide. Attached is my crude diagram of that wiring; no guarantees it's error-free.

The fuses on either side of the Orion XS 50 are Blue Sea Systems 7721 Fuse Blocks. These use the same mega fuses that I used in all of the Victron updates.  These have a fuse post and a wire post on each end which make the connections easy.

The boost solenoid was replaced with a more robust Blue Sea Systems 9012 unit.

The remote start relay was a Tyco V23232-D0001-X001, and I replaced that with a Bosch 0-332-002-150 that I had saved from my ignition relay update.  The old Tyco is in the spares box should I ever need it.

The 90A breaker that feeds the ignition relays was replaced with a new one, Klixon SDLA-90.

Rivnuts were installed at all mounting points on the plate, so everything mounts to the plate the same way. I also added standoffs on the two ends so when installed in the coach, it no longer has a bow.

The remaining re-settable fuses were mounted to the plate and connected with a bus bar to eliminate the extra wiring that had been added. These are all new components as well; the original ones had too much rust/corrosion to reuse.

re-applied power, and no magic smoke was released   Dash voltage gauges now respond normally as well. We will be making a few battery maintainer updates, actually they are almost done but since the coach is now getting a spa treatment they will not be finished for a bit.

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Re: Update Isolator/Auxiliary Start Panel

Reply #2 – February 13, 2025, 01:21:19 pm

Nice writeup Steve!

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Re: Update Isolator/Auxiliary Start Panel

Reply #3 – February 13, 2025, 02:46:25 pm

Wow! Wish you had owned my coach before I bought it. Big reliability upgrade without introducing a new problem. That shows a lot of thought, knowledge, and experience.

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Re: Update Isolator/Auxiliary Start Panel

Reply #4 – February 15, 2025, 07:51:38 pm

Really like all the updating to that area. It looks fantastic and is a true update of old components, that don't live in best environment. I wish I got royalties off that picture TommyD posted of the battery to battery install. I used as my guide as well. I am patiently waiting to hear about the updated inverter and house battery install. I'm sure to be impressed.
Tom

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