z425 will not start

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ACF

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new battery on charge

did the following test
battery positive side to cable going to solenoid
off .001 run .001 start .001
battery positive cable to starter
off 14.21 run 14.21 start 13.8
battery positive to solenoid connection that has white attached
key off 3.44 run 14.21 start 13.96
battery positive to white wire disconnected
key off .003 run 14.19 start .004
ground off .00 run .00 start peak .064

solenoid bad ?
Hi ACF,

Here is an example of the voltage drop test:

https://www.bing.com/videos/rivervi...E312C6FCE7034ED0B900E312C6FCE7034ED&FORM=VIRE

The trick is power has to be flowing on the circuits with the key turned to the crank position while measuring with the DVOM. This phenomenon of seeing a voltage reading on the meter with the leads on a single cable or wire is what tricks many people.
 

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Do not have a charger connected when testing but make sure the battery is good.

Only test for voltage drop with the key switch held in the crank position for each meter reading test as you move around.

Remember to only test one (the same) wire or cable at a time from end to end.
 

ACF

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no charger new battery
battery cable to solenoid in start .002
battery to starter in start 12.90
battery to white wire on solenoid 12.88
battery to white on solenoid wire not connected to the solenoid .008
 

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no charger new battery
battery cable to solenoid in start .002
battery to starter in start 12.90
battery to white wire on solenoid 12.88
battery to white on solenoid wire not connected to the solenoid .008
You will need to check all safety switches working backwards from the white solenoid trigger wire if I am understanding the reading correctly.

Maybe this video will help.
 

ACF

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it's me again
took star tech drawing # 2 sn 120001, did a continuity test on all the wires got a good long beep on all except for the ones going to the coils just got a beep then nothing, could d1 or d2 be bad, also the coils have jb weld on a post of each coil, but when i disconnect the ground wire and jump solenoid with the aid of starting fluid the engine will start, but connected will not start

also my other concern is the k2 interlock on drawing, the wires did not match the pins on the drawings when i did the test,
when key placed in run position do get a clicking in the k2 relay

tested all safety switches seat not working and right handle replaced,

did voltage check at the key switch
b position: had voltage during off, run and start positions 12.67 volts
s2 position, had voltage only in the run position 12.55 volts
s1 position, no voltage at any position
a position, voltage in run position only 12.65 volts
m position, no voltage at any key position

pto will engage in run position

thank you for taking the time to teach me and help with this problem
 

StarTech

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If S2 has voltage and S1 don't in start position then the ignition switch is probably bad or one of the wire terminals is not making contact.

And which ground wire are you referring to? Is it the 601A White wire at the engine?

And explain how the wires didn't on the K2 relay. If different in color look for the wire number print on the wires. I seen different colors used but wire has so matched to diagrams.
 

ACF

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If S2 has voltage and S1 don't in start position then the ignition switch is probably bad or one of the wire terminals is not making contact.

And which ground wire are you referring to? Is it the 601A White wire at the engine?

And explain how the wires didn't on the K2 relay. If different in color look for the wire number print on the wires. I seen different colors used but wire has so matched to diagrams.
disconnected switch reconnected had voltage but not constant when did have power the starter would engage only, owner reported that key switch was replaced

wire 601a at engine connect checked out good continuity at c4m once it became a black wire there was no continuity, going to the wires at the coils.

the k2 relay i have the following wire connections
wire 704 gets continuity at position 87a upper left if looking from back of mower
wire 606 gets continuity at position 87 upper middle if looking from back of mower
wire 601a gets continuity at position 85 upper right if looking from back of mower
wire 420 gets continuity at lower left pin if looking from back of mower
wire 100r gets continuity at lower right pin if looking from back of mower

thanks
 

StarTech

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First the ignition switch connector must have a bad F56 - Packard - Gm - Delphi wire terminal. They like along spring hinge leading to a loose connection

Second at the connector the white wire changes over to black the female wire is probably loose or not making contact due corrosion.

100R should be on terminal 30 of the relay.

420A should be on terminal 86 of the relay

420C should also be on terminal 86 of the relay

Both are good as the relay operates and the fuel solenoid operates. Note both of these are +12vdc whenever the relay is active.

601A should be 601B at the relay and course it has continuity if the ignition off that part of the magneto kill circuit. DO NOT apply +12vdc to this circuit it will destroy both ignition coils. Plus may damage the relay, ignition switch, and associated wiring.

704 White should have continuity whenever the relay is active. It also should on terminal 86. This completes the ground circuit for the starter solenoid.

There is no 606 on the wiring diagram but 601B should connected to 87A relay terminal and 704 should be on 87 relay terminal. From your info these appear to have been reversed. Which would explain why the start solenoid isn't working.
 

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Two things happen when you apply power to the wrong circuit. One is you let the "magic smoke" out and two, you likely created more problems than you started with.
 
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