Kubota BX25 sputtering under load (not fuel filters?)

[Old Coot]

Thanks for the replies.
I didn't mention that since it only happened after running for some time, I thought I would try a lower thermostat. I put a 160 in and it didn't help. It still will run up the hill when cold or till it warms up, then it will sputter, I can then turn around and back up the hill with no problem.
I going to try filling it every half hour and see if that helps. If it doesn't I'll bite the bullet and change the fuel pump. I just don't like crawling under these thing anymore.

 

[Old Coot]

Well the latest so far. I tried to mow yesterday and it continued to get worse till it stalled out a couple of time. Finally got it to the barn.
I started at the top and checked the top filter and had nothing when running the fuel pump. Then to the pump itself and had nothing. But there was also nothing coming to the fuel pump from first filter. Took it loose and nothing there either. So I used the air hose with low pressure up through the feed line and here came the fuel. Then proceeded to drain all the fuel. So then I put a clean rag across the inlet to the shop vac tank and pushed the hose all around inside of the tank. That way I could see if I got anything out of the tank. I came up with some stuff that looked a little like broken pine needles and some black crap. Then I put a wash cloth on a sewer cleaner and move it all around the tank for longer than I like to admit. Even got some stuff with that.
I put it all back together and it started up and run fine. Is that a fix????? I didn't get a chance to run it around for a while because it started to rain as soon as I started it up.
I wish I knew an easy way of removing that tank to make sure it was clean.

 

[aczlan]

Thanks for the update, hopefully that fixes it...

Aaron Z

 

[thepumpguysc]

I'm not sure of the size of the neck but you could try a shop vac.. just take the sock/filter off on the inside of the vac tank.. No need to worry about fumes exploding like on a "gas" engine..
There is def. something in the tank slowing the flow..
Good luck & glad ya found it..

 

[dodge man]

You might want to dump some anti algae treatment in it just in case that’s the problem.

 

[Old Coot]

Thanks for the replies. The pump guy, I did use a shop vac. I put the rag at the entrance to the vac tank not the inlet of the hose. That is how I knew what I got out. But after finding a site that showed the fuel tank, I'm not sure the vac could get down to the outlet of the tank. The tank tapers down to the outlet and keeps the vac hose from getting there. Wish I would have seen that before I started. I might have taken the line loose before the first filter and used some air to blow it out of the tank that way with some fuel.
I was to busy today and haven't had time to put the mower deck back on. I hope to try it tomorrow. Kubota could have made it harder, but they would have to work at it.

 

[Old Coot]

Well, I finally got up enough courage to try it out today. Actually I took my 357 mag with me in case I had to put it out of it's misery.
I mowed for 3 hours and it never sputtered once. So I thought, why not screw my good feelings up. So I tried to mow the hill where always fell on it face on. NOT A MISS.
I was almost afraid to shut it down for fear it would revert back to it's old self.
But I know I will always be waiting for it to do it again. Thanks for listening me whine about my troubles.

 

[Blondie70]

If it does it again...I would fill tank completely...then get a good siphon hose that could reach the bottom feed area of the tank....start siphon into an empty fuel container. Move the hose around the bottom of the tank as it is flowing. You will get everything out that way. If the hose stops flowing, just ease it up out of tank and any crap that is plugging the hose will be sucked to the end of hose..just pull it off and continue siphoning. I would get about 5 gallons of fuel out to be safe.
Then....pour the fuel back into tank thru a screened funnel or a filter of some type. You will have a clean tank then.

 

[Paul Gillis]

Last winter I started to have the exact same problem on my 2010 BX25. It was hard to duplicate the problem because I didn't realize it only happened going up hill with a heavy load/demand on the engine. It started to happen again this past spring so I brought it to my dealer and I asked them to drain and flush the fuel tank. They ended up only draining and refilling the tank. (I forget the reason they said they could not flush the tank - maybe too hard?) In any case they changed the filters and no problems all summer and then last week the same problem all over again. Sputtering engine going up hill under heavy load near stalling until I turn the tractor downhill. If I manually surge the throttle lever I can stop the engine from cutting out. Once I get the tractor to level ground I can limp it back to the barn. The next day it will run with no trouble. I will try to check the fuel tank for debris/obstructions. Does anyone know how hard it is to replace the fuel tank? Thanks for any feedback.

 

[aczlan]

Our BX2660 has a saddle tank, IIRC, there is a 3/8" hose that runs across from one side to the other to equalize the fuel level

Yes, my father in law went out and spent a couple of hours mowing with it today. He was very happy with it when he came back in and said that it ran perfectly. My wife has also used it to mow the yard and she said that it behaved well.


With ours, it ran ok(ish) cold, warm or hot with a full tank, but once it got down to the bottom half of the tank, it started having issues.

If you want to have an easy test, run it to less than half a tank, pop the hood and put a quart container down by the injection pump. Remove the line for fuel coming into the pump, put it into the container and turn the key to "on" position. Fuel should flood out into the container. If it does not (or if it just barely trickles out like mine did), its a bad pump, or plugged filters. If it just trickles out, pull the mower deck, then remove the input line to the fuel filter (over a pan). If fuel rushes out (as mine did), its probbaly the pump.

Aaron Z

The pump fixed ours for a month or two, then the problem came back. Sent it to the dealer, they pulled the tank, flushed it out and it has been good ever since.

Aaron Z