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auto bilge pump

Could be the dash switch, a fuse in the switch lead, the float switch, or the wiring connecting the auto side.

The float could be built into the pump or separate but near the pump.

Best approach is a thorough inspection; fuse swap is easiest - if that isn't the issue, get a test light with a long enough grounding lead and start probing.
 
If your boat is equipped with the Auto/OFF/Manual helm switch, and if you leave the boat unattended and moored, please understand that these are dangerous.

If you need more info, I'd be glad to explain why.
 
Why is this Dangerous (in addition to Battery Drain) if properly Fused ?

If your boat is equipped with the Auto/OFF/Manual helm switch, and if you leave the boat unattended and moored, please understand that these are dangerous.

If you need more info, I'd be glad to explain why.
 
The draining of a battery is not the problem. If a bilge pump needs to remove water in our absence, let's give it all the battery power we can.
The issue is where the Auto/OFF/Manual helm switch receives it's power.
These typically receive power at the helm, which is dependant on the hull harness, which is dependant on the MBSS making a battery bank selection. When we leave our boats unattended, we usually turn the MBSS off. Now the helm power is also off, so how is the "Auto" mode able to power a float switch?
Answer: It cannot!

Even if this was a good idea, the other issue is remebering to leave it in the Auto Mode and/or accidentally bumping it off.

Rule 101: A main bilge pump "Float Switch" power should come from an "un-interruptible" power source..... I.E., Non-Switchable.

No matter how you slice it, no matter how you try to rationalize it......., this type of Auto/OFF/Manual switch is a bad idea.
These companies that make and sell these switches should be ashamed of themselves.:mad:
 
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I totally agree !

My Primary Pump was hooked up this way with an Auto/Manual switch w/Indicator (at least it has no OFF) at the helm.
But when the Perko Battery switch was set to OFF......All Bildge Pump operation where suspended.

Instead of rewiring it !

I added a slightly smaller (more Energy efficient) Bildge Pump & Float Lower in the bildge.
It's always connected directly to one of the batteries in Dual Battery set-up.
If it was a heavy rain period (Lots of Battery drain), I could use the other battery for starting.

FYI: I was resistant to Not putting a fuse (others recomended) on this New primary pump line (I finally went with a fuse that 2.5X it's pump recommended fuse rating).

Hence, the old Primary pump is now my Secondary pump !





The draining of a battery is not the problem. If a bilge pump needs to remove water in our absence, let's give it all the battery power we can.
The issue is where the Auto/OFF/Manual helm switch receives it's power.
These typically receive power at the helm, which is dependant on the hull harness, which is dependant on the MBSS making a battery bank selection. When we leave our boats unattended, we usually turn the MBSS off. Now the helm power is also off, so how is the "Auto" mode able to power a float switch?
Answer: It cannot!

Even if this was a good idea, the other issue is remebering to leave it in the Auto Mode and/or accidentally bumping it off.

Rule 101: A main bilge pump "Float Switch" power should come from an "un-interruptible" power source..... I.E., Non-Switchable.

No matter how you slice it, no matter how you try to rationalize it......., this type of Auto/OFF/Manual switch is a bad idea.
These companies that make and sell these switches should be ashamed of themselves.:mad:
 
Sounds like a float issue if an issue at all auto turn on automatically as boat is filled with water float should be very near or as they mentioned built in to bilge pump once located can be tested with volt meter of test light can try to manually lift float and see with switched to auto if u can hear pump or fill your boat up with water above float and see if it turns on not the best way lol
 
if you cant see a float switch near the pump please see how many wires are coming out of the motor and the color of each....if you have 3 or more its probable a built in switch....you say the pump works when in manual.....that eliminates an air pocket problem that is common in boats where the hose is built into the boat where you cant see it...if the hose has a dip in it that will hold enough water to fill the diameter of the hose...if the system is air tight then rising water in the bilge will not push the air out and the water never rises enough to prime the pump..i say never but it can be intermittent...the fix for that is to drill a very small hole in the pump output tube...this allows the water to push the air out...you will get a little spray when the pump operates but what the hell...you got everything wet down there anyway..
 
i forgot to say that with the air pocket problem the bilge will have water but the pump is running but not primed...
 
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