Onan Marquis Indiana 5000 generator

Spark Plug # RS17YX for Onan 167-0272 on RV Gensets ...

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Generator Parts Spark Plug # RS17YX for Onan 167-0272 on RV Gensets ... for this plug require the spark gap to be set at .025" (25 thousandths of an inch).

Onan Gen HGJAB What is the best spark plug and gap? - Heartland ...

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Jun 8, 2013 - 3 posts - ‎3 authors Also what is the the correct gap on the plugs? ... brands · Generators; Onan Gen HGJAB What is the best spark plug and gap? ... Gap: 0.025

They are generally sealed, as it affects the mixture. You can take the carb off, put on the bench and remove the shut off solenoid at the bottom of the bowl, remove black cap on main jet, remove screw, and unscrew the bowl. To set back up you will need to ideally check on a load bank, for ability to pick up full step load,

Can you be more specific than just starter problems?

To determine if it is from the breaker use a

Tong Tester


These would indicate what current is being consumed by the load.

Sounds like a flat battery.

Either you have a kill wire ( if I remember it is the brown wire) that is disconnected on one end or the other Or your in coach switch is bad.
Check the switch this way

Remove the switch from the dash/ mounting surface unplug the brown wire - start the genset - ground the brown wire - it should kill the motor
If it kills the motor your switch is bad

ONANS ARE PRETTY QUIRKY AS IT IS NOT CONSUMER FRIENDLY. THE GENSET IS DESIGNED FOR ROUTINE AND SIMPLE MAINTENANCE PERFORMED BY THE OWNER, AFTER THAT, U WILL NEED TO TAKE IT TO THE NEAREST DEALER OR CUMMINS DIESEL REPAIR SHOP.

on your generator ther is a reset if thats not it check for fuses if still no then u neda check the wires in the pluges if no then ur generator it self needs re bilt

a 10 year old genset with only 45hrs on it...sound like the carb may need replace. working with these rv units for 6+ years has taught me that you cannot clean one well enough to fix it. you will need a new carb. your local onan dealer can help. when new the warrenty makes known that 1hr per month under load will keep the carb clean and problem free. evaporating gas leaves deposits and eventualy plug fuel jets. no replacement parts are recommended. i've personaly worked on rv's with 200+ hous and no issues at all. hope this helps, good luck...

1. Does the generator stay running when you start it the first time?

2. What color is the housing on this generator? Try to get the model number and serial number.

If the genset is shutting down on the first try, then your probably not creating voltage. However, if this is an older unit then the genset may stay running although no voltage is created. Place a volt meter on the genset to check for output voltage.