Reisender wrote:
Idle-Up wrote:
Thanks for all the replies - I recently sold my 2019 Newmar New Aire which had an 8 kw genny to purchase my newer 2020 Renegade Verona with an 8 kw Onan as well. Upon delivery, I immediately noticed a contrast difference in the generators quieter operation and lower idle speed which compelled me to contact Onan to investigate the difference.
Yesterday I finally managed to have a short conversation with my busy friend Bill Stubbs, Bill is possibly one of the most knowledgeable guys on the planet with Cummins, Allison transmissions as well as Onan.generators. Bill is the one who uncovered the poor engine performance in RV’s which was caused by a protocol called “Fuel Sense” which was bogging down Cummins engines in RV’s. Fuel sense caused over-shifting in an effort to save fuel.
Bill mentioned that while all Onan diesel generators use an inverter module, the newer Onan’s now use a different inverter based processor protocol, which allows the Onan to idle slower, as well as control lower operating speeds to make the somewhat noisy Kubota’s engines a bit quieter and more fuel efficient. He mentioned these new diesel protocol’s were inline with the new 2500i and 2800i inverted based smaller gas generators recently released.
Glad you got to the bottom of it mike. Hopefully the new and improved version will also reduce the amount of invertir boards that owners are going thru.
Cheers and stay safe on the road.
Reisender thanks for the reply - Regarding the many board failures in Onan’s, the most common cause for this occurs when the generator is using to the same battery set as the main engine.
When the owner can’t start the RV’s engine because of a depleted battery, he then starts the generator. The problem occurs as he attempts to start the engine “while the generator is running”, the extreme momentary high amperage load of the starter windings overloads the Onan’s 12/120 volt circuitry, causing the control module to fail.
Regretfully, this is a short coming of the Onan system since it’s not uncommon for an owner to have a depleted chassis battery from all the processors running when the engine is off then start the generator to power and start the main engine.
Regards - Mike
