L3560 Sputtering / Stalling out @180hrs

zephyr

New member

Equipment
L3560
Aug 17, 2025
2
2
3
Maine
Long time lurker - first time poster. I've had a 3560 for just over a year, kept indoors overwinter, just about 180h on the engine, 85Gal of diesel burned so far according to the system. Had a tech out for the 50h service last fall, nothing of note, other than an issue where running it at extended periods of time at low RPM's the alternator does not have enough power to sustain combustion & will drain battery, replaced with genuine (and expensive) kubota battery from local dealer, still have issue, trickle charge if necessary.

Ran it for about 3 hours yesterday doing some heavy lifting / log moving. Ran fine, until the rpm's dropped in two tiers and then it died. Water / Fuel separator was fairly full, right at line, that bulb is really fragile and getting it off involved bending the bracket that holds it to the frame ( real great engineering there!) purged that, possible algae? don't know enough to , cleaned and replaced. purged air, Was able to start - ran for 5-10min lowest RPM. same sputter out.
Next up removed drained an re-installed fuel filter, (its Sunday and local NAPA doesn't have a new filter on hand), took a while to purge air but got it to turn over and run for another 5-10min, moved it to a safer flat location and revved to 1500rpm, ran for a bit and then it dropped rpms this time 3-4 times before shutting off.
Suspect bad fuel? using ULSF offroad. or fuel pump issue but will solicit some advice to whats next first before draining the whole system. Dealer isn't open until tomorrow. Don't really want a service call.
Video of symptoms at the following link.
 

Bee-Positive

Well-known member

Equipment
BX1880, FEL, Tooth Bar, MMM, QH, Ballast Box
Nov 16, 2022
315
301
63
Amsterdam, NY
Just brain storming here to see what sticks.

"Water / Fuel separator was fairly full," after only 6 tank full sounds like a fuel issue.

Averaging 15 hrs. / month it's sitting quite a bit. Condensate can form in the tank especially in an unheated garaged - it has been very humid here in the NE.

Are you bulk storing fuel or using cans? Have you used any fuel additives? Is the filter visibly gummed up or is it just water? Maybe try a different vender for fuel just to see if the problems goes away.
 
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zephyr

New member

Equipment
L3560
Aug 17, 2025
2
2
3
Maine
Determined blockage in fuel system prior to h2o separator. Had to blow the lines out with air to clear. Pumped all the fuel out I could, added Algecide to new fuel after purging air she runs good.

Will keep more full tanks & algicide in fuel mix for the future.

plastic tanks according to my shop tech are more prone to it, and he’s seen this happen more in the past 5 years or so.

Just brain storming here to see what sticks.

"Water / Fuel separator was fairly full," after only 6 tank full sounds like a fuel issue.

Averaging 15 hrs. / month it's sitting quite a bit. Condensate can form in the tank especially in an unheated garaged - it has been very humid here in the NE.

Are you bulk storing fuel or using cans? Have you used any fuel additives? Is the filter visibly gummed up or is it just water? Maybe try a different vender for fuel just to see if the problems goes away.
Thanks BEE

Re: Fuel - Mowed my field early July and ran a full tank through, Different fuel vendor up there, had about a half tank and only used sporadically in July I Generally keep it above 1/2 full tank with 2x 5.5Gal Fuel cans at the ready to top off when needed. Try to not store the fuel for too long, but maybe the last month heat / humid was enough to cause issue.
 
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Russell King

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Lifetime Member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
6,542
2,150
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Austin, Texas
You may have gotten grass, bugs… into the fuel tank also IF you don’t have any type of strainer in the tank fill. You would NOT be the first to have that type of debris clog a fuel passageway!

Glad you found it! And good for you for trying to prevent the occurrence of biological growth in the tank.