1973 8hp 4 Speed

[PaulHoskins 24]

I picked up a nice 1973 8hp 4 speed from a younger guy for $100. It was purchased without a fuel tank and was non running. Looks complete with some newer parts. I charged the battery and when I try to turn it over the solenoid clicks but the started doesn’t engage. I tried a new solenoid. I replaced the battery. I tried another solenoid. Same thing, solenoid clicks but doesn’t try to turn over. The keyswitch is new already but I picked up a new keyswitch today. I haven’t tried the keyswitch yet but will tomorrow. What am I missing here?

[troutbum70 858]

Run a heavy wire from the positive post on battery straight to starter and see if it will engage that way, if not then starter needs repaired. If it does engage then maybe incorrect ignition switch or wired incorrectly.

[PaulHoskins 24]

I have jumped the solenoid and the starter does engage. I assumed wired wrong if this keyswitch doesn’t fix it. 

[squonk 43,361]

If the solenoid clicks it sounds like the switch is working. If you have a voltmeter, check the battery voltage at the battery cable at the solenoid. If there is 12volts + there test that spot with the key on start. If the voltage drops below 11.5 you may need a new cable. Also check your main ground connections for dirt /paint

[953 nut 59,252]

10 hours ago, troutbum63 said:

heavy wire from the positive post on battery straight to starter and see if it will engage that way, if not then starter needs repaired.

Don't forget about the ground wire! Electricity needs a return path.

Lets take a logical step by step inspection of your starter problem.

Is your PTO in the ON position, a wheel horse will not start with the PTO on.

Have you had the battery load tested at an auto parts store?

Have you cleaned and tightened all electrical connections including grounds?

Are all fuses good and fuse holders cleaned?

If these have all been done, we can check components of the starting system as follows; don’t skip a step or you may miss the problem.

Take a pair of automotive jumper cables and connect the black cable to your battery  "-" and a good clean spot on the engine. Now connect the other cable to the large post on the starter and touch the other end to the battery "+" terminal, does the starter turn over? If the starter turns over the battery and starter are good. If it didn't turn over try the same steps with the battery in your car/truck, if that cures the problem then the "good" battery wasn't so good.

Presuming the starter turned over move the jumper wire from the starter post to the other end of the wire going to the starter which is one of the large posts on the solenoid. If the starter turns over when the battery is touched by the jumper as before then that cable is good, if not you have found your problem.

Presuming the starter turned over move that jumper to the other terminal of the solenoid, connect the other end to the battery and use a small piece of wire to temporarily connect the battery "+" terminal to the small terminal on the solenoid, this should cause the solenoid to close and the starter to turn over. If not, the solenoid is probably the problem.

If this was successful remove the large jumper cable and use the small jumper wire to the small terminal of the solenoid, the solenoid should close and the starter turn over. If not the cable to the battery is the problem.

Presuming all of these have been successful remove the black jumper wire and repeat the small jumper to small terminal, if the starter turns over the ground is good.

If all of these components test good then remove your ignition switch, be sure the transmission is in neutral, parking brake on, clutch depressed and PTO off. Use a small jumper to connect the terminals that were connected to the “B” and “S” terminals of the ignition switch. If the starter turns over then the PTO switch and other safety switches are operating properly and your ignition switch may be bad.

[PaulHoskins 24]

Thanks guys! The cable from the starter to the solenoid was bad. 953 Nut, thanks for that step by step diagnosis plan. I’m no mechanic or electrical guy, so that was dummy proof. She runs like a dream now!