Generator dies after load
Been searching for fixes for this for months and the forums that post ideas always die without a fix so here we go. I have a Onan 4K generator that started out dying after 10 min no matter what. ...
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Stootz01 wrote:
Been searching for fixes for this for months and the forums that post ideas always die without a fix so here we go.
I have a Onan 4K generator that started out dying after 10 min no matter what.
I installed a new fuel pump/filter and carb, oil change, no fix.
I took the air filter out while it was running to inspect it and noticed it would keep running but when the AC was on it would die...so I changed the air filter...no change under load but it would keep running without a load.
I then took the metal air filter cover and left filter on....would run under load but would then die after 10 min.
I then discovered there was an additional after market fuel filter on it under the RV so I bypassed it, changed the spark plug while I was at it and discovered that it would run for 30 min under load before it died.
I then discovered a youtube video of someone claiming that draining oil below the low level line would keep it going. Comments suggest that was a mirical worker and it seemed to fix the problem for a lot of people.....but not mine....
I'm getting closer to nailing this down but I'm out of ideas
Give me suggestions....I'll do it man!!!!
Gen has 216 hrs on it
Have you checked HZ/voltage while running and immediately before unit shuts down..? Very common for a over/under hz safety shut off to occur if governor/engine speed is not set exactly correct. When switching between no load/full load governor struggles to maintain correct rpm to keep hz/voltage in safe/no safety shut down range.
I set 5500 onans for 62-63hz under no load. When genny goes to full load the rpm drops just enough to drop the hz to 59-60. if it goes below 58-56hz for 10 seconds the unit will shut down on low hz safety shut down... Above 66hz will also trigger a safety shut down. The efi models are a little different but similar...
Whatever you do, DO NOT drain oil to below low level line and run unit like that utube vid suggests, unless you like rebuilding engines. 1 of the worst web recommendations I've ever heard...lol.
jmo
