ONAN 5500 Generator Woes

[Heppkat]

My 2010 ONAN 5500 generator (111 hrs) will start and load up, but it shuts down after about 10 minutes and seems to be hot. Breakers are good. I have proven the priming pump/fuel filter, have removed and cleaned the carburetor, oil level and quality is good. The only thing I have yet to do is to clean out the muffler spark arrestor. My question; what else could be causing the unit to drop the load and shut down?

Thanks.
Peter Heppleston
2010 Monaco Monarch SFS33

[Heppkat]

Thanks for all your responses. It turned out to be the fuel pump not delivering the required volume at 75% load. New pump/filter unit $240.00CDN.Happy camper. Thanks again.

[10forty2]

Should be easy enough to test if it's shutting down due to temp..... while sitting still, open the cabinet door, crank the genset and run a hi-flow fan over it. If it doesn't shut down, turn off the fan and see if it shuts down. If it does, then it's probably overheating.

[mccsix]

FYI there are 2 filters, one in plain sight at the engine the other underneath just before the fuel pump.

[1Thunderjet2]

my 5500 had the problem of running great for an hour then stall out.
restart would only run 10 mins and then stall.
found problem was fuel pump overheating, replaced with airtex pump under $40
never a problem after that

[TugCE]

Mine will shut down after a couple of hours of run time. This only happens when parked. This was a lot of fun last year when we lived in it for three days after Hurricane Irma last year!

I've been told that the fuel pump may be getting hot due to age which causes the shutdown. I've not had the time to tear into it yet but I plan on replacing the pump and possibly installing s fan to aid in cooling when we are stopped.

[D_E_Bishop]

Does it show a trouble code? If so what is it? If not or you don't know how to access the code, read the manual. The codes can be a problem to read but at least look for one, they are in the manual.

[IB853347201]

What error code is displayed?

[NutHouse2016]

Outlet from tank for genset is higher than the coach motoroutlet, if low gas/fuel level may be the problem. Make sure you havea quarter tank and see if makes a difference.

[Sam_Spade]

Heppkat wrote:
My question; what else could be causing the unit to drop the load and shut down?

Oil level....be sure it is FULL, not just OK.
Fuel level in the tank.
Then....fuel pump.
Seems like a lot of them fail around 8-10 years old and they will run for varying amounts of time when they start going bad.

They do get pretty HOT after running a while.
Check the air intake for a plastic bag or similar.....and be sure that the door on the gen itself is closed.

[Chris_Bryant]

Will it start back up, or does have to cool down?