Late to the discussion here but I've hit the issue with the 36 error code on my two week old Cummins/Onan 5500. Really, it was the first time I used it for more than just a few minutes when it was demonstrated during the PDI.
After priming, it started right up... I let it idle for maybe 5 mins before starting to apply any load. Then, using the recommended sequence, I added the load in increments. All was good for about 20-30 mins when I heard the gen set stumble and stall. Now I can't get the darn thing to start although it cranks just fine.
Using troubleshooting guides I've found on the Cummins/Onan site, I've checked the oil level (it's close to full and right between the hashed marks as suggested), fuel level reads about 7/8 on the gauge but I know it's gotta be close to full, checked the spark plug wires to make sure they're snug, and checked the fuel lines for any shut-off valves (haven't found one). Also checked the air cleaner and it looks brand new, as you would expect.
After much reading, it would appear that the fuel pump is the most likely issue... at least that seems to be the problem most folks with this code had. I guess my next step is to find a Cummins/Onan dealer in the area.
Any tips or guidance from you guys that have had to bring yours in for warranty support?
Mike, Sue, Sissy and Little Man
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