BX23S blowing 5 amp fuel pump fuse

[brants51]

Good evening,
My tractor recently died because of what appears to be a blown 5 amp fuel pump fuse. It has plenty of diesel fuel, the filter is new, not clogged and it appears all safety switches are physically closed. I replaced it and the again the fuse blew after cranking it over.
1. Could it be the pto or hst safety switch? (Nope, fuel on own circuit)
2. Fuel pump bad?
2. BX23s wiring diagram?
Any suggestions appreciated. Thanks

 

[Bee-Positive]

Electrical diagram here BX23S WSM
What year and how many hours on the tractor?
Bad fuel pump or fuel pump connections...maybe?

 

[brants51]

2020, 475 hours, fuel pump connection looked fine. I'm planning to check continuity/voltage today or tomorrow

 

[GreensvilleJay]

That 5 amp fuse and fuel pump are connected to the alternator using the red/yel wire.( IG termianal )
Not too sure why....

FYI... if you have a full tank of fuel , you can run the tractor without the fuel pump. have no idea how long I ran mine for, but noticed the connector had unplugged itself !

 

[brants51]

When I pulled the fuel line off of the exit side of the pump, nothing came out? I'm around 1/4 tank

 

[Bee-Positive]

I assume you replaced BOTH fuel filters, before and after the pump.

Loosen the fuel cap and pull the inlet side off the fuel pump, see if you're getting fuel from the tank to the pump. Have a bucket and rag handy. If little or no fuel, then filter or tank outlet is clogged and maybe the pump is running dry, it might overheat and blow a fuse.

If getting fuel to the pump reconnect the inlet and take the outlet hose off, direct the outlet of the pump into a bucket with a short piece of hose. With a good fuse installed turn the key on without starting, you should hear the pump run and see fuel going into he bucket. If not, bad pump or bad connection.

 

[brants51]

Both filters are new. The filter (less than 12") before the pump inlet appears to be full of diesel, but I have not checked right at the inlet yet, but I will tomorrow. Thanks

 

[Bearcatrp]

Using Kubota fuel filters?

 

[brants51]

Yes

 

[Hugo Habicht]

The fuel pump has it's own fuse. So it is either the fuel pump faulty or the wire from the fuse (red arrow) shorting to ground.

Measure the fuel pump current by connecting the two probes of an ampmeter into the fuse socket.

Check this wire for chafe. Sorry about the poor scan quality, it is from kubotabooks.com WSM. Maybe you have a better quality scan where you can read the cable colour.

 

[brants51]

Will do! I'm planning to try and troubleshoot today. Image was good enough, I downloaded the workshop manual for wire colors.

 

[GreensvilleJay]

post #13 , in the electrical section has a GREAT wiring diagram !! think White Tiger posted it ?

 

[Hugo Habicht]

post #13 , in the electrical section has a GREAT wiring diagram !! think White Tiger posted it ?

Did not see that, always forget about this thread. I was using the WSM link in post #2.

 

[brants51]

Update:
1. Confirmed the fuel pump inlet is getting fuel
2. Measured incoming voltage, 12.4v (section 4.7.1 in manual)
3. The fuel pump measured OL/ no conductivity (section 4.7.2 manual)

This leads me to believe the pump is bad. Calling local dealer.

 

[Hugo Habicht]

An open fuel pump does not fry fuses unless it died together with the last fuse.

As far as I can see the pump is electronically controlled, so measuring with an ohmmeter may lead to high impedance / open circuit.

 

[GreensvilleJay]

Yup, fuel pump is open , is no longer good.
It's a pricey part from dealer( $240 CDN !! ) , several available elsewhere for far less ( $20-$50).

here's one that'll work...

https://www.amazon.ca/Cyleto-Electric-Universal-Carburetor-HEP-02A/dp/B098JDR8QV/ref=sr_1_8?crid=LTFRWJUQXMOI&dib=eyJ2IjoiMSJ9.Zo1q-FFYrSMMQlA8ji3iCopNKLOpvBGYaAzWL0GjMFTczKZLviQZKjCN7hsAKXeVJ8N46l201xrmxKO6fD2PG0vZzEKdxpHkdZannufHH28CXteNnmis4RKxgHOZnR1csuC3VJeEyWTz6Fvs2zlQpoFGBdlRyoT-fL88ug1P1pNSNYabUCzhEdMauITswqmxiatIhf34N_r67RgxEZT01VVnyYkWOfD-J_b1JRZbycI2zb8UfwyMVIATiYXKaTDgXbXfUxQHXhBs4g6O0jkprBquQ_Yf72i9xSUvEIKeWw4.1tg1Gy953CCOLEVojsai-39LX99lX9NIzsJcl67CWRs&dib_tag=se&keywords=diesel+fuel+pump&qid=1773762348&sprefix=diesel+fuel+pump%2Caps%2C136&sr=8-8

Just cut connector/wires off the dead one.

 

[brants51]

$268 here, the amazon one is tempting, but the reviews are so so

 

[GreensvilleJay]

I ran on in my dieselled forklift for 10+ years. Others ,here, have been using them.
I've used one to filter old fuel for 5 years....

probably cheaper than the tax or shipping for the OEM one, so well worth the 'expense'.

 

[brants51]

Worth a try and I'll purchase a backup. thanks

 

[Bearcatrp]

Is this normal for a fuel pump to die out with this low of hours? Starting to get nervous about my 1880 with all the issues folks are having with the BX line of tractors. I only have 250 hours on mine.