KX 121-3 -2004 year - wont run

Keseyman

New member

Equipment
KX 121-3 Kubota Excavator
Apr 22, 2025
3
0
1
Dunbarton NH 03046
I have one of these rigs -- has been running great -- I mean flawless a well kept machine with the 42 HP.
I had serviced all of it except fuel filter.
Last week while traveling in rabbit mode it started to cut out -- I tried cutting back on throttle, but it was all done.
Has full tank of clean new fuel with some Lucas additive in it.
Fuel filter was a mess and changed it and filled glass filter and new filter installed. It is I think pretty simple design with this year of Mfg -- there is no spin on filter -- I have bled it all the way up to the final injectors many times while using a jump assist on battery -- fuel coming out buy hard to tell when air is out and or if that the real problem,
I have been careful to not overheat starter.
Looking for ideas of course of anyone who has experienced the same and been successful on re-starting
 

Russell King

Well-known member
Lifetime Member

Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
5,886
1,697
113
Austin, Texas
Put the throttle to full speed position and bleed it some more is my only advice.
 

Keseyman

New member

Equipment
KX 121-3 Kubota Excavator
Apr 22, 2025
3
0
1
Dunbarton NH 03046
Thank you -- have tried that -- after staring at it the fuel pump is right there and when key is on no clicking -- so maybe what I thought was fuel was residual in the lines and the pump went and caused shut down -- its a FACET POSI FLO 60106 -- going to get one and try that. Thank you for advice !
 

whitetiger

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Staff member

Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
3,061
1,505
113
Kansas City, KS
The electric fuel lift pump quitting would most certainly shut it down even with a full tank of fuel.
 

whitetiger

Moderator
Staff member

Equipment
Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
3,061
1,505
113
Kansas City, KS
I didnt know I had an emergency shut down switch -- I got no manual with the machine -- is it on the engine or in the cab ?
Actually, there is only a manual shut-off lever on your machine on the injection pump.
Any model newer has a red knob in the RH console at the very back.