Rich16 32 #1 Posted September 26, 2018 I just got a running p220 Onan (engine off 520) and could use help in how to wire it up to start as a 'bare' engine. There are some YouTube vids on 220's off machines but none show how the guys actually wired them up to start - help? I don't want to do anything (too) stupid and screw or burn something electrical up. Bought the engine as a spare for the '91 520h I recently posted on the forum and want to get it tuned and ready to install if ever needed. And yeah, it's kinda fun Many thanks for all the sage wisdom offered here. 2 Share this post Link to post Share on other sites
WH nut 553 #2 Posted September 26, 2018 Just jump 12 volts the the+ side of the coil off jumper cables, ground the motor and the + side of the cable to the large stud on starter and and jump solenoid. 1 Share this post Link to post Share on other sites
Rich16 32 #3 Posted September 27, 2018 Thanks WH nut - my electrical skills are poor and I kinda sorta understand what you're saying but just to be sure. You lost me after grounding the engine. Can I use the battery on one of my horses (without removing) similar to jumping a car? If I connect battery side + to + on the coil and then ground between tractor frame to engine. What is the large stud on the starter? I only see two similar screw contacts on the solenoid along with a small clip connection between them. Is one of these where I connect positive? Apologize for my electrical ignorance - just don't want to screw anything up! Share this post Link to post Share on other sites
WH nut 553 #4 Posted September 27, 2018 13 hours ago, Rich16 said: Thanks WH nut - my electrical skills are poor and I kinda sorta understand what you're saying but just to be sure. You lost me after grounding the engine. Can I use the battery on one of my horses (without removing) similar to jumping a car? If I connect battery side + to + on the coil and then ground between tractor frame to engine. What is the large stud on the starter? I only see two similar screw contacts on the solenoid along with a small clip connection between them. Is one of these where I connect positive? Apologize for my electrical ignorance - just don't want to screw anything up! Yes use jumpers like you are jumping a car. Neg to ground Pos. to the the battery wire on starter. Take another jumper wire to the + one the coil. Use a screw driver or jumper wire from the battery wire on starter to the small terminal on solenoid to spin the starter. 1 Share this post Link to post Share on other sites
lynnmor 6,820 #5 Posted September 27, 2018 Since the engine should not be operated without a battery connected, the output of the voltage regulator should also be connected. 2 Share this post Link to post Share on other sites
Rich16 32 #6 Posted September 28, 2018 Lynnmor - do you mean the 12v off the center prong of the rectifier that charges the battery? Share this post Link to post Share on other sites
lynnmor 6,820 #7 Posted September 28, 2018 27 minutes ago, Rich16 said: Lynnmor - do you mean the 12v off the center prong of the rectifier that charges the battery? Yes. Share this post Link to post Share on other sites