Starter Selenoid alternate uses?

[67EB_in_619]

Can a starter selenoid be used as a battery isolator? Any other uses? I have one mounted to a 2.3L Ford 4Cyl.. on the block .. and there is another one mounted on the firewall. Just looking for explanation.. I am pretty positive there was a second battery at some point.. but not sure what this extra hardware is from.

Thanks for the help!

 

[76Broncofromhell]

Starter solenoids aren't rated for continuous duty so in short, no. That solenoid is probably for raising and lowering the outdrive in the boat.

 

[74bob]

They use solenoids in some motorhomes as isolators but that is the cheap way ??? not the right way. I see this mistake all the time and it doesn't make any sense. If you are planning to run a second battery for winch use don't isolate the batteries. The electric winch needs all the amps as can be delivered for maximum pull power. Just use common sense while winching and you won't have dead batteries.

 

[67EB_in_619]

Everything (seems to) work with this thing not hooked up... it cranks... but dont run... (see other posts). I will just ignore this thing. I am sure it was some cheap arsed way of doing dual batteries.
(outdrive lift works without the thing hooked up.. i thought of that one too )

 

[72_EB]

Maybe he was running some extra lights with it???
I've got this but haven't used them in a while.

 

[68beast]

My painless dual battery kit came with a solenoid (called an isolater solenoid by painless) are you sayin this is the wrong way to get dual batteries ???

 

[67EB_in_619]

I think I figured it out.... It seems that there were some accessories that you would want to use with the motor off... so perhaps there was a battery that was used for the accessories but isolated from the battery used to crank the engine.. so you can always start up... it looks like a starter selenoid... but could be something else.. like the painless setup. The cranking battery was only engaged when the ignition was on. Clever.

 

[Broncobowsher]

A starter solenoid is only rated for intermittent duty. I tried to use one as a battery isolator 10 years ago. Burned it out. But you could use it for something like a horn relay if you needed it.
If you have 2 batteries with one of those diode isolators, you could use it to give yourself a jumpstart.
But if you want to use it to isolate 2 batteries, you can get some that are rated for continuous duty. Try RV or Boat shops. Make sure it is rated for continuous duty.

 

[chuck]

The continuous duty sol. is not the cheap way to isolate batterys. You get a full charge with solenoids but not with diodes. And with a push of a button both batteries are tied togather.

 

[67EB_in_619]

I am not sure exaclty what this solenoid is (continuous vs intermitent) nor am I sure it was used as an isolator in the pure sense of it all...

My guess is that the PO wanted to only engage the second battery when the ignition was on, so that the accessories could drain the first one with out worries that there will be nothing left to start.... so once ignition was on, the batteries would be wired in parallel and I assume both would charge off the alt. Maybe it is a continuous sol?? any easy way to check?

 

[jcmessing]

I had on eon mine for a horn relay.

 

[mtn_bronco]

used by every snow plow manufacturer to run the plow pump