170 with KAWASAKI FV420 engine not charging battery

Hitechluddite

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Looking at the system a little there is just a single large red cable from the starter to the battery and a small red wire from the ign switch to the bendix. Where does the charge voltage come from and what is the Achilles heel in the charging system?
 

bertsmobile1

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Firstly
Get a JD technical manual for your mower
Cost is less than 1 hours of a techs labour charge.
Written in plain English complete with descriptions so you know what each part is, what it does & how it works

Next the engine will have al alternator fittied and that will be connected to a regulator
Look for wires coming out from under the flywheel
two will be the same colour, these are the AC feed to the regulator, follow them to the regulator .
The regulator will have a 3 pin plug, Kawasaki do things a little different as the 2 AC INPUTS are together & the DC output is on one side
The 4th connection, DC Ground is via the body of the rectifier .
Measure between the two AC wires, engine running full speed, should be 28 V AC or better
Measure between the DC wire & ground connection should be 13 V DC or better

IS your mower just a plain 170 ? ( 100 series ) or are there letters to go with it.
 

StarTech

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Wrong again.

FV420V Doesn't exist. The FC420V uses a 6 pin regulator for the ones with electric starter. Recoil versions don't have the electrics for charging. Boy I wish posters would look-up the engine's IPLs before posting so they what they talking about. Please stop assuming things. Also these regulators will not have an output voltage if the battery is not connected or the main fuse is blown. I actually had a few these to have a negative output on B+ when the battery wasn't installled.


PS the three terminal Kawasaki regulator uses negative half wave regulator; hence why one AC stator wires is tried to the B+ to complete the electrical circuit. So whatever you do never ground either AC terminals or B+ terminal while the battery is connected.
 
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Hitechluddite

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Sorry it is a FC420V Straight 170 It has a 15Amp blade fuse near the Battery but even with it pulled The mower still starts, I don't see anyregulator module mounted around the motor.
 

StarTech

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If this is like the 175 the fuse is for regulator only and there is a separate circuit breaker for the rest of the mower. BTW the IPL says the that fuse should be a 20 amp blade fuse; the 175 has it at 20 amp and the circuit breaker is a 25 amp version. There is also a 10 amp fuse for the electric PTO.

Also the voltage regulator should be located in the operator station.
 
Last edited:

Hitechluddite

Active Member
Joined
Dec 14, 2018
Threads
16
Messages
58
Firstly
Get a JD technical manual for your mower
Cost is less than 1 hours of a techs labour charge.
Written in plain English complete with descriptions so you know what each part is, what it does & how it works

Next the engine will have al alternator fittied and that will be connected to a regulator
Look for wires coming out from under the flywheel
two will be the same colour, these are the AC feed to the regulator, follow them to the regulator .
The regulator will have a 3 pin plug, Kawasaki do things a little different as the 2 AC INPUTS are together & the DC output is on one side
The 4th connection, DC Ground is via the body of the rectifier .
Measure between the two AC wires, engine running full speed, should be 28 V AC or better
Measure between the DC wire & ground connection should be 13 V DC or better

IS your mower just a plain 170 ? ( 100 series ) or are there letters to go with it.
Just a straight 170 made between 89 and 90 I think. Thanks as I get time I'll dig into it and see what I find....
 
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