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Kenny O.
Kenny O., Motorcycle, ATV, Mules, Side by Side's Product Specialist. All Brands
Category: Motorcycle
Satisfied Customers: 1021
Experience:  Worked for Kawasaki Motors as a Product Support Specialist (Factory Support) for 24 years
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I have 2009 4010 mule fuel injected JK1AFCM119B502549. It

Customer Question

Jeff I have 2009 4010 mule fuel injected JK1AFCM119B502549. It starts fine and has good power than after a few minutes starts bucking with no power. I removed the tank, cleaned it out good and replaced the fuel pump and filter. No improvement, doing the same thing. The tank was quite dirty so is it possible its the relief valve. I ran the three second flow check and only a trickle comes out. Have not ran the pressure check
Submitted: 1 year ago.
Category: Motorcycle
Expert:  Kenny O. replied 1 year ago.

Thanks Ernie, you have a 2009 KAF620M9F, can I get the ours on this unit, a brief description of what its used for, also when the engine starts to act up, can you give me a little more description maybe like the speed, what it drops down to ? You say your replaced the fuel pump, correct ?

You have the spec's on the fuel pump it looks like, the pressure is an important test as in the flow test, are you sure the tank was completely cleaned after installing the new pump ?


Customer: replied 1 year ago.
200 hours, I just purchased it from a horse farm, I am planning on using it for farm use myself. I did not replace the entire fuel pump assembly, just the pump and filter aftermarket, Caltec. I high or low gear, basically boggs down no power above idle. New pump and filter failed the 1.8 oz/3sec flow test have not checked the pressure. Could it be the relief valve?
Customer: replied 1 year ago.
Sorry thats 2000 hours, completely flushed out the tank dried it and wiped it out with a clean rag.
Expert:  Kenny O. replied 1 year ago.

OK, Kawasaki makes replacement filters fir that pump ??? You need to check the pressure and flow, you have me confused "WAS THE FUEL PUMP REPLACED" ?? read your second to last response "I did not replace the entire fuel pump assembly" then you go on to say ​the "new pump and filter failed" ???

Relief valve has nothing to do with the injection, you can unplug that hose for testing purposes, it allows the tank to breath

Customer: replied 1 year ago.
I replaced the small cylindrical pump unit within the snap-together complete fuel pump assembly. The complete drop-in unit is $600 from Kawasaki. The little filter is on the end of the pump inside the plastic housing. There is a breather vent for the fuel tank. The relief valve is in the snap-together fuel unit that drops into the fuel tank.
Customer: replied 1 year ago.
Not this:
Just this:
Customer: replied 1 year ago.
Am I making any sense?
Expert:  Kenny O. replied 1 year ago.

I'm going to post up a bulletin and its explains how to replace the filter using Kawasaki Genuine parts, if you haven't do so I would suggest you do that first and or get me some reading on the fuel pressure and volume. The pump pressure needs to be 41-46 psi and then the volume is 50ml or 1.7 ounces for 3 seconds.

Give me a little bit and I will post up the bulletin.


Expert:  Kenny O. replied 1 year ago.

At this point lets not worry about the relief valve, also if you were saying the tank was as dirty as it was you might have some clogged injectors, lets get your pump squared away first, OK ?

Customer: replied 1 year ago.
Looks good, I did replace the filter at the same time I replaced the INTERNAL PUMP, after I completely cleaned out the fuel tank. So with clean fuel, fuel tank, new internal pump and filter as shown in the bulletin, the flow rate test is much less than 1.8oz in three seconds. I will check the supply pressure tomorrow and let you know.
Thanks Ernie
Expert:  Kenny O. replied 1 year ago.

Thanks Ernie, good job !

Customer: replied 1 year ago.
OK I plumbed a pressure gauge in the fuel line between the fuel tank and engine. The pressure is at 40 psi at idle but will drop to about half that under acceleration. The flow rate is much less than 1.8oz/3sec, but it seems to be running ok for now. New filter,new pump(just the pump itself Kenny)clean fuel, pump module taken completely apart,everything cleaned out VG. I still suspect the fuel regulator or the compartment that is glued together that the regulator pops into. There could be crap in that compartment or in the regulator itself. My next move will be to replace that entire POS fuel pump module with an external mounted 12V,40-46psi, 48Gal/hr pump either with or without an external/internal pressure regulator.
Expert:  Kenny O. replied 1 year ago.

Morning Ernie, yeah that's not good, I think you are right, if there was a lot of crap in this tank then the pump is just worn out, just remember going aftermarket then you loose all the safety features of the OE, I know the price of that stuff id crazy, even at dealer cost $413.27 its crazy, there is an updated part number if you decide to go that way, I'm sure that is your problem. Good luck ! Part ####-##-####