Bilge pump blowing fuses

[webcraft]

.
It's a wee auto job that sits in the sump.

Worked fine for the year the boat sat on her mooring, but the bilge has got very oily over the last 100 hours of motoring down the Irish Sea and half way across Biscay - is this the likely cause, or is it more likely I need to redo the wiring?

Any diagnostic suggestions?

- W

 

[Skipper_Christoph]

Can't see how oil should cause the fuse to blow. First thing is to check the pump. Is it spinning freely or blocked?

 

[TernVI]

.
It's a wee auto job that sits in the sump.

Worked fine for the year the boat sat on her mooring, but the bilge has got very oily over the last 100 hours of motoring down the Irish Sea and half way across Biscay - is this the likely cause, or is it more likely I need to redo the wiring?

Any diagnostic suggestions?

- W

Stop pumping your oil overboard?

 

[jamie N]

As Skipper Christopher said, does the pump actually turn; check physically and visually.
Try to test it from a different supply, and check the cabling, with a VDM and visually if you can.
If you've a 2nd auto pump, you might swap them and see if the fault follows the pump or the circuit.

 

[vas]

+1 on the pump
most likely it's on it's last legs shaft sticking and resistance too high.
99% replace

V.

 

[markspark7]

Have you got a DC clamp meter ? Just stick it over the cable to see what it';s actually pulling before and after a clean down.
If current is higher than the rated then pumps knackered or needs a good service, if the amps are where they should be , check the actual fuse as there do deteriorate if the trip out repeatedly.