Float Switch Blows Fuse

[bros250]

I have a Rule float switch on my bilge pump which immediately blows the 10 amp fuse when thrown in the on position. The bilge works fine with the switch on the control panel. I upped the fuse to a 20 amp which still blows. I cannot find any wiring issues. The fuse is inline a few inches from the hot lead going from the battery directly to the float switch. Any suggestions for troubleshooting??

[springhead]

I have a Rule float switch on my bilge pump which immediately blows the 10 amp fuse when thrown in the on position. The bilge works fine with the switch on the control panel. I upped the fuse to a 20 amp which still blows. I cannot find any wiring issues. The fuse is inline a few inches from the hot lead going from the battery directly to the float switch. Any suggestions for troubleshooting??

you did all you can do, change out the float switch

[bros250]

The float switch is brand new

[Sig_Mech]

Just because something is new doesn't necessarily mean it is good. Did it work when first installed and recently stopped working? Are you sure of the installation and wiring connections? If the bilge pump works from the on switch but not from the float switch, it could only be two things: the switch or the wiring connections when it was installed

[jtexas]

the pump works from the helm - I'm assuming that circuit is fused similarly in which case we know it's drawing less than 10 amps at startup.........yet the other circuit is drawing more than 20 amps?

the only explanation I can come up with is a short directly to ground between the float switch and the pump

[bros250]

thanks to all
i replaced the float switch with exactly the same model. it had worked previously prior to the original switch going bad. i maintained the same wiring when installing the new one. i will recheck wiring as well as fuseholder for corrosion, etc.

[jtexas]

"short directly to ground between the float switch and the pump" - I should have said, "between the fuse and the pump".

Also should have said, the solution to a blown fuse is *not* to double the size of the fuse - good way to burn up a pump. Or your boat.

[burroak]

If a float switch draws in excess of 10 amps, remove it from the circuit.

[wcsparky05]

j tex is right about the fuse. they are there to protect you and expensive parts on your boat. never just size up fuses. if you're going to do that, just take out the inline fuse. right?

start over if you haven't fixed it yet. first of all, what is your wire gauge? if you are undersized that will pop your fuse. what is your bilge pump rated at? amps and gpm? and also, motors ramp up meaning start-up draw will be considerably more than running power. take the bilge pump directly to the battery without the in-line fuse. if that works, install the rated in line fuse and see if that pops. if not you have faulty wiring or undersized wire.

Or, if you did not take your -neg from the bilge pump directly to the battery, i.e. you piggey-backed it with your blower motor ground or your stereo you will not receive correct voltage and could pop your fuse. hope this helped. take care.