Design Flaw

[dave lowry]

Today I learned that, at least on my '76 Royale, the battery boost switch
is useless if the cranking battery is completely dead (as mine was this
morning because the right access door had been left unlatched allowing the
emergency light to burn for several days).

The Battery boost switch is powered by the starting battery. If the
starting battery is LOW, hitting the boost switch will bring the house
battery bank on line to help start the engine. However, if the starting
battery is DEAD, you can't activate the boost solenoid.

Fortunately, the fix is easy. Replace the hot lead to the boost switch with
a fused hot lead (16 ga.) from the house batteries. Now you'll be able to
start the motor even if the starting battery is completely dead.

I'd call this a design flaw. Any contrary opinions?

___________
Dave (& Dege), '76 Royale /_][__] [_] | "SR JAMES"
Santa Barbara, CA *0-------OO--* (our hobby)

 

[john dolan]

>I'd call this a design flaw. Any contrary opinions?

I agree it is a problem, but I think they designed it for what they
considered the most common failure mode, and decided to forget about your
situation. An alternative solution would be to include a switch to power
the solenoid from either battery bank that had juice.

- --
Regards,
John 74 Glacier

 

[dave lowry]

I agree it is a problem, but I think they designed it for what they
considered the most common failure mode, and decided to forget about your
situation. An alternative solution would be to include a switch to power
the solenoid from either battery bank that had juice.

Good suggestion, John. And it should be fairly easy to put the switch under
the hood in case it's ever needed.

Thanks,

___________
Dave (& Dege), '76 Royale /_][__] [_] | "SR JAMES"
Santa Barbara, CA *0-------OO--* (our hobby)

 

[john dolan]

> And it should be fairly easy to put the switch under
>the hood in case it's ever needed. Thanks, Dave

Thanks for bringing the issue to the floor... I believe it is one of
those things that one just doesn't think about till it happens.

- --
Regards,
John 74 Glacier

 

[patrick flowers]

>
> Good suggestion, John. And it should be fairly easy to put the switch under
> the hood in case it's ever needed.

Not to mention, just running a wire from both batteries to the relay
post will provide a path around the isolator allowing discharge of both
batteries. An power diode in each wire would fix that, but the switch
is probably a better fix.

Patrick
- --
Patrick Flowers
Mailtoatrick

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