float switch bilge pump not working NOW working

[floating bee]

Hi everyone

Well my float switch bilge pump was not working-I thought it had packed up but I cleaned it tried to flick ithe float up still no joy-then I checked fuses and low and behold one was broken-swapped a 5 AMP fuse and behold it worked! So anyone who has the problem check the fuses first before declaring a failed bilge pump!

[smileypete]

Sometimes a blow fuse is a symptom of a failing bilge pump, worth checking the current it draws with a multimeter on the 10 amp range, and comparing to what that model should draw.

 

That said, small value glass fuses themselves can be unreliable and just break, blade fuses are better.

 

cheers, Pete

~smpt~

[floating bee]

Sometimes a blow fuse is a symptom of a failing bilge pump, worth checking the current it draws with a multimeter on the 10 amp range, and comparing to what that model should draw.

 

That said, small value glass fuses themselves can be unreliable and just break, blade fuses are better.

 

cheers, Pete

~smpt~

OK-where do you put the red and black leads(multi-metre)?

Edited March 14, 2013 by floating bee

[BEngo]

OK-where do you put the red and black leads(multi-metre)?

 

 

Take the fuse out again and put the red lead on one end of the fuse holder and the black lead on the other. MAKE SURE the meter is set to the 10A range. Switch the bilge pump on and read the meter.

 

The fuse may have blown because something got stuck in the pump impeller. Worth having a good look to see that its not still lurking to do it again. The bottom part (impeller chamber) comes off most bilge pumps and you can give it all a clean and a peer up the outlet pipe/flush with a hose.

 

N

[smileypete]

Wot BEngo says, but check the red and black leads are in the right sockets for measuring up to 10 amps, which are usually called something like 10ADC and COM.

 

After finishing be sure to unplug the leads or move the red lead to the socket normally used for measuring volts, usually called something like VΩmA.

 

Trying to measure volts with the red lead in the 10 amp socket often results in a blown fuse somewhere or overheated meter leads.

 

cheers, Pete

~smpt~

Edited March 14, 2013 by smileypete

[floating bee]

Wot BEngo says, but check the red and black leads are in the right sockets for measuring up to 10 amps, which are usually called something like 10ADC and COM.

 

After finishing be sure to unplug the leads or move the red lead to the socket normally used for measuring volts, usually called something like VΩmA.

 

Trying to measure volts with the red lead in the 10 amp socket often results in a blown fuse somewhere or overheated meter leads.

 

cheers, Pete

~smpt~

Thanks for that Pete-When I put the two leads on the fuse holder what readings am I looking at?

What would be considered "normal"?

[Paul C]

A better check would be to measure the resistance of the bilge pump. Remove the fuse. Measure the resistance between the wire to the bilge pump (where the fuse was) and a neutral point.

 

Its possible the pump failed in a dead short, which will blow any fuse and your multimeter (probably has a built in fuse...) if you tried to measure the current flowing.

[BEngo]

A better check would be to measure the resistance of the bilge pump. Remove the fuse. Measure the resistance between the wire to the bilge pump (where the fuse was) and a neutral point.

 

Its possible the pump failed in a dead short, which will blow any fuse and your multimeter (probably has a built in fuse...) if you tried to measure the current flowing.

 

 

Resistance is useless!

 

The resistance of a static bilge pump winding will be pretty low and probably more affected by the state of the commutator than by anything else. A dead short would be informative, as might an open circuit, but the pump is presently working so there isn't a dead short now so the current should be within meter limits, unless it is an intermittent dead short and reappears when the meter is connected.

 

N

[Paul C]

Yeah I agree its not so much use in this particular instance. I had a similar issue except with a shower pump that kept blowing fuses. I thought it was worth mentioning though, to see what others thought of the idea.

[smileypete]

Thanks for that Pete-When I put the two leads on the fuse holder what readings am I looking at?

What would be considered "normal"?

Should get an amps reading while the pump is running, by lifting the float or something. The normal reading depends on what model pump it is, a small one probably shouldn't draw more than 2 or 3 amps.

 

When mine went it was drawing over 6 amps instead of 2 or 3, also lifting it out and shaking it you could hear the water sloshing around inside the pump motor.

 

cheers, Pete.

~smpt~

Edited March 15, 2013 by smileypete

[floating bee]

Should get an amps reading while the pump is running, by lifting the float or something. The normal reading depends on what model pump it is, a small one probably shouldn't draw more than 2 or 3 amps.

 

When mine went it was drawing over 6 amps instead of 2 or 3, also lifting it out and shaking it you could hear the water sloshing around inside the pump motor.

 

cheers, Pete.

~smpt~

Well it is working but I will do an amp test.