BX2200 Electrical problem

[harveyc]

I'm glad I brought you back!

Hope you don't mind if I run on your thread here with my own electrical issues, but maybe you'll get a laugh out of it and make your day.

This blown fuse problem has been around for probably up to two years and I'm finally getting around to trying to figure it out again since my neighbor (disabled electrical engineer) had offered to try to help. The thing that had given me some concern is that I feared I might be getting some overheating of the engine. For some time I've had another issue with my BX22 that has puzzled me. Engine RPMs would drop and respond sluggishly. I changed fuel filters last year or so and didn't really seem any help there so I wondered if the engine might be getting hot since the problem usually (I think?) would happen more often if I'd been running under moderate or heavy load for a while.

Yesterday my dealer loaned me their service manual and we noticed that the fuel pump is on the same circuit with the 15amp fuse. How could the fuel pump function with a blown fuse for two years, we wondered!!???!!! Well, it dawned on me and a smile appeared on my face as I laughed at myself. The fuel pump apparently has not been functioning for a couple of years yet the tractor usually performed adequately (sometimes great, sometimes just "okay"). We did run a current limited to 3 amps with the key turned off and with the fuel pump wires removed the draw did drop to about .25 amps, so this does appear to be the answer to my problem though we won't confirm until the new fuel pump arrives on Monday. It's costing $125 for a tiny pump and the dealer indicates they sold one earlier this year and also one last year, so this may be a common problem (though it may not always short out when it quits functioning).

I guess the elevation of the tank is adequate for the injector pump to suck on fuel to usually provide sufficient fuel, but not always under load. I just would never have thought that to be the case. I feel a little dumb for letting this go on so long but it's just another one of those learning experiences I can chuckle at.

Thanks,

Harvey

 

[NY_Yankees_Fan]

Harv

When you turn the key before starting do you hear the fuel pump running??? Once I had something hit the wire that feeds power to the pump and take the pump out of service. I had similar problems as you, changed filters as you did, no change. Then I took a real close look at the fuel pump and noted one of the wires were gone. Made the repair, have not had a problem since, now before starting I listen for the clicking of the fuel pump running before I start the engine.

 

[Volfandt]

harveyc, great feedback

Yours is definitely a head scratcher. Generally, an electric problem would be the last issue I'd trace when troubleshooting an intermittent fuel delivery type problem on a diesel.
With the exception of the fuel shutoff solenoid not working that is

The fuel tanks on these BX's are slightly higher than the fuel injection pump and apparantly it's "just" high enough for gravity to run the engines under normal operating conditions. Course it's when these little powerplants go under load is when the fuel delivery must be able to keep up.
You must have done a very good job in changing out the filters in keeping the introduction of air into the system at a minimum.
Funny thing is that the "self bleeding" feature of the BX's rely on the electric fuel pump to purge the fuel system

Live and learn

 

[harveyc]

NY_Yankee's Fan: No, I here no noise from the pump. It's very clear to me now that it's not working at all. In fact, it's probably a hindrance to fuel flow!

Volfandt, I need to apologize to my thoughts about those Japanese engineers when I changed my fuel filters. Baloney, I thought, the fuel pump does not prime these filters!!! LOL I actually have some experience with other tractors that are sometimes hard to prime (Oliver 1365) and slightly pressurized the fuel tank to help get fuel to flow (remove fuel cap and use part of an old inner tube and used compressed air). All of this seems so obvious now!

 

[rdsaustintx]

AMAZING it would run with a dead pump.

You'll know when the pump is working. It's a noisy little sucker.

 

[harveyc]

I can confirm that the fuel pump was not functioning and tractor performance is improved with the new pump (and fuse does not blow). The old fuel pump was most likely hindering fuel flow (my neighbor who was helping tried blowing on the new pump and was unable to do so). I wonder if the fuel pump could just be eliminated since performance was often fine when it was not functioning. Other diesel tractors I have don't have one. $129 was a bit excessive for that small pump but I didn't complain since the dealer let me borrow their service manual.

I did also discover both of my headlights had blown bulps (maybe related to when the pump blew the fuse?). The high beam would work on both bulbs but they are unused on the BX22. The crazy thing is that Kubota does not sell the bulbs alone. The entire headlight assembly costs over $50 each. Fortunately, it appears my Napa store found a cross-referenced replacement bulb (though the computer showed it as 100w instead of 40w/45w, but that's probably wrong). The picture on the computer looked like a perfect match. Cost there was just over $12 each.

 

[Tom_H]

Right after I had my Woods BH6000 backhoe put on my BX2200, I started blowing fuses endlessly, every time I turned the key to the start position. Had to take it to the dealer twice. They had to trace every wire and after several hours, finally found a tiny short in a harness. There was no way to tell whether the process of installing the sub-frame caused any damage, but it seemed to me like there must have been a correlation. My memory is getting a little fuzzy with age, and I can't remember the exact nature, but there was also a fuel flow problem of some sort with it. No problems since the repair however.

 

[scotty088]

These 3cyl engines shake and vibrate wildly at idle.Given that fact Wire connectors on my glow plug and water temp sensors have broken and been repaired several times.I would check for chafing and insulation bare spots through-out your wiring harnesses.I have also had to repair the bracket that holds the air filter assy.It cracked due to vibration.2004 BX2230 450 hrs.I havn't had any issues with fuel leaks or blown fuses.