We were dry camping in unseasonably warm weather. It was quite hot so had both AC's running. Genny quits after about 30 minutes. Started it again and same thing. Then started and got error code 47. Says it's an ignition issue and could be related to the board. A few comments on the Net suggest high ambient temps could be the problem. Long story short. We moved to a full service campground with considerably lower temperatures so didn't need the Genny. After 6 days, we headed back to the dry camping area. This time it was maybe 20º cooler and the Genny fired up and ran like a champ. It ran for at least 3 hours before we shut it down. Since then, it's been running daily for several hours at a time over the past 3 days with no shutdowns.
Anyone have a similar problem and have any words of wisdom? Also, anyone replace a board on an Onan 5500 circa 2005?
One caveat, we haven't needed the AC so don't know how it will perform under load. The most we've powered was the microwave and a small 1500 watt space heater.
I had similar issues with my 5500. I now have a pretty extensive knowledge of common issues. I found that the codes it shows are many times misleading as well. 2 items I definitely replaced, and no issues since. Often overlooked by DYI people. I'll try to post pics if I still have them.
1) There is an igniter circuit that fires the AC side. 2 wires that slip on and can be hooked up either way so no worries. It is a set of brushes that are located right above the control panel. Cost is @ $55 and easy to replace if you are capable. I did have to shimmy it a bit to remove it because the brushes we so worn it heated up the holder. Items can be found on Amazon, Cummings parts, Walmart(yep), and other similar sources.
2) Fuel pump, filter, and all rubber hoses. If they have never been changed, do it now! Cost is low. Pump heats up and stops working, sounds like its running but its not pushing gas. Also, the rubber hoses get soft inside where you cant see it and sucks closed. Also found on amazon. I was stranded at a rest stop in over 100 degree weather in Arkansas last year when mine broke. Luckily there was an auto parts store an exit down and I sent my son after parts and gerry rigged it. I'm an old mechanic and had him get a low volume fuel pump replacement for a 1970 ford 360 engine. Changed it and all the hoses, clamps, and filter and ran like a champ.
I need to add, I paid a RV road mechanic $300 to originally look at it and diagnose the issue. His diagnosis was a control board after repeating every test I did provious to his arrival. I purchased the board from Cummings in Memphis and installed it, same issue. After exhausting many avenues, I talked to the Cumming shop that furnished the board and he directed me to the brush assembly. I replaced them and ran fine. I re-installed the old board and it was also fine. They would have refunded my money, but I was so happy they helped me and kept the board as a spare. (The fuel pump was a later issue down the road). I now carry an extra set of brushes and fuel pump. For $100 I'll keep them on board for spares. Also, keep extra 5/16" and 1/4" fuel hose and new clamps.
Sorry if this was a long reply but I hope it helps! Good luck!
Dick
