No crank, good battery, new relays

[Dagwood11 0]

1995 520 H 20 HP Onan motor. I am experiencing electrical issues on the start circuit. Started fine, pulled it out of the garage, put the deck on and go to start it, nothing. So far I have replaced the 3 relays under the battery tray, cleaned the relay blocks the best I could and bypassed the neutral switch (put a jumper between the brown and purple leads. All I get is clicking from the middle relay, that is the relay with the blue wire from the starter. I can start it by bypassing the blue wire to the starter and jumping the starter from the positive and the plug where the blue wire connects. So whatever the issue is, the blue wire is not getting power. Any ideas. It starts perfectly without any outside help other than jumping the starter with a jump wire. 

[953 nut 67,307]

This drawing shows all of the components of the Starting system. Take a look at it and if you have further questions or need help deciphering the drawing we can help you. Need to know if the blue wire is light blue or dark blue. Be sure the PTO is off and all connections are clean and tight.

PS;  safety switches or relays are seldom the problem but that seems to be where everybody starts. 

 

 

[Dagwood11 0]

Thank you.
I'm dumber than a bag of rocks when it comes to electrical/electronics. I don't really understand the schematic, all I can understand is that the wire to the starter solenoid is the one that has no power. How to test it, I have no clue. Where to start to test it, I have no clue. How to use a multimeter, I have no clue, but I do actually have a couple of them. 

 

 

[gwest_ca-(File Mod) 12,332]

Figure out how you can measure 12 volts DC (Direct Current). Your meter may show 100VDC which just means it will measure up to 100 volts. Ground the negative wire to a good chassis ground or battery negative. Now with the red test lead follow the power from the battery to the solenoid checking for battery voltage into each switch and out of each switch. There are notes in the schematic showing the state of the switches - operator in seat, pto off as examples. You are testing the start circuit so you may need a helping hand to hold the ignition switch in the start position.

Notice the start relay gets it's power directly from battery + on a purple wire. The rest of the circuit controls what the start relay does. Wired like this so the start relay gets maximum power via a short cut without going through all the safety switches.

Keep us posted on what you find and help will walk you through it.

[Dagwood11 0]

Thank you so much. I will keep you up to date. 

[Pullstart 70,524]

How are your grounds?  

[ri702bill 12,423]

That tractor should have "the dreaded 9 pin connector" in the wiring harness - a source of all sorts of electrical issues over time. Separate the halves and thoroughly inspect it for signs of corrosion & overheating. Repair / replace as necessary. My .