Author Topic: Mikuni VM Econo Jet Carburetors  (Read 4195 times)

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Mikuni VM Econo Jet Carburetors
« on: January 27, 2016, 11:22:04 AM »
I will start this off and others can add their thoughts as appropriate.  Our experience has been that the Mikuni carbs have been very reliable.  However, with that said, in order to avoid problems this is the approach that we take with all new-to-us Kawasaki sleds that come into our possession:

1.  Thoroughly clean the carburetor body inside and out. 
2.  Remove air bleed screw, remove idle stop screw remove needle jet, remove pilot jet, remove main jet, remove econojet. 
3.  Blow out all passages with carburetor cleaner and compressed air.  We have even taken to using a small wire cleaner to make sure that the passages are clear of all obstruction.  Clean the needle jet - there is a moat at the top that plugs easily.  Make sure that this is clean and that the idle air passage in the needle jet is clear.
4.  Re-install air bleed screw and idle screw.  Set to factory set points.
5.  Install new jets - pilot, main and econo to original factory spec [one caveat here is that we have our own mix for Intruders.  Kawasaki used a different mix over the various years.  We have settled on 25 pilot, 150 mail, and 120 mag/130 pto econo jets]
6.  Replace needle and seat.
7.  Generally no need to replace bowl gasket if it is not damaged.
8.  Replace econojet hose.
9.  Replace "O" ring at base of needle jet.
10.  Confirm that the needles and slides match factory specification for model and year of engine.  Find correct parts if the numbers are not correct.

I have probably forgotten something here and welcome other input.
« Last Edit: January 27, 2016, 01:40:22 PM by mswyka »
Intruders:  1978, 1979, 1980, 1981 Custom
Invaders:  1979 340, 1980 440, 1980 440 TOC Custom
Projects:  1979 Invader 340, 1980 Invader 340, 1979 Intruder 440, 1982 Intruder 440, 1980 Drifter 340 F/C, 1972 Panther 303 ...


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Re: Mikuni VM Econo Jet Carburetors
« Reply #1 on: January 27, 2016, 11:31:21 AM »
Sounds like you have a good practice going there 8)

I would add checking the choke(plunger seal, and proper adjustment) and sync the carbs.

Also it seems many people ask about where to get that o-ring for the needle jet... here are some part numbers but I have found that the John Deere ones are the lowest priced and pretty easy to find a Deere dealer or even order on-line 8)

Carb O ring: Kawasaki pn # 92055-044, Arctic Cat pn# 6505-042, John Deere pn# R34812
69 Panther 372 JLO
73 Gilson 435
80 Kawasaki Intruder 440
81 Pantera,93 Jag,(2)94 Cougars, (2)Prowlers, (2)Z440's
2002 Polaris XCSP 800

Lloyd (ljm)

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Re: Mikuni VM Econo Jet Carburetors
« Reply #2 on: January 27, 2016, 03:46:26 PM »
Well explained Mark!

77 SST
78 Intruder
79 340 Invader
80 440 Invader
80 Drifter (bought new)
80 LTD 4/6    X2

Several Deeres