Quieting down a ONAN 5500 Gen set

[MConnelly]

For some reason Keystone choose to exhaust the ONAN 5500 gen set on our '09 Fuzion 403 on the right side , right under the bedroom window and facing the most common sitting areas under the awning.
Simple enough to loosen the exhaust pipe and swing it over to the other side angling it back wards to exit between the bedroom and salon slide. (pipe needed to be extended)
All was well there unless the heater was running, then on days with no wind the exhaust gas would find it's way into the heater air intake and set off the carbon monoxide detector.
I installed one of the turbo exhaust stacks and that solved that problem as well as quieting the unit some.
Still not satisfied with the noise level, I installed a small muffler at the very end of the exhaust pipe.
PERECT!!. The gen set is quieter than my AC units . Quite a bit quieter.
Ran it for three days straight over the past weekend and no issues what so ever. Got the muffler at the local auto supply. 1 1/2" in and out, about 14" long, 5" diameter. Painted it black...looks great.

[jbcason]

Originally Posted by MConnelly

For some reason Keystone choose to exhaust the ONAN 5500 gen set on our '09 Fuzion 403 on the right side , right under the bedroom window and facing the most common sitting areas under the awning.
Simple enough to loosen the exhaust pipe and swing it over to the other side angling it back wards to exit between the bedroom and salon slide. (pipe needed to be extended)
All was well there unless the heater was running, then on days with no wind the exhaust gas would find it's way into the heater air intake and set off the carbon monoxide detector.
I installed one of the turbo exhaust stacks and that solved that problem as well as quieting the unit some.
Still not satisfied with the noise level, I installed a small muffler at the very end of the exhaust pipe.
PERECT!!. The gen set is quieter than my AC units . Quite a bit quieter.
Ran it for three days straight over the past weekend and no issues what so ever. Got the muffler at the local auto supply. 1 1/2" in and out, about 14" long, 5" diameter. Painted it black...looks great.

Could you post pictures?

[DieselMatt]

Sounds interesting for sure. My exhaust is mounted where yours was. So far I haven't had any issues with it, but I also don't run mine all the time. I just run it long enough to charge up the batteries and/or run something with it and then it goes off.

[rclark]

I have the same 5500 gen set. I moved the exhaust to other side just like you did. Unfortunately I did not get the installation instructions, but I did read in the operation manual a warning about back pressure causing overheat of unit.
You also need to make sure the pipe has enough down angle to allow the water to run out.
Maybe they are just protecting themselves, but it is something you might want to check on.
Dealer installed mine and I was not happy with the installation, left huge gaps in the floor. I sealed it all up with gorilla tape and seems to work and doesn't look bad. Still has the correct airflow for cooling but keeps the water out of the storage compartment.

[MConnelly]

The "down Angle" is a must!! I also drilled a small hole in the lowest point of the muffler to drain any condensation.

We do a lot of Vending using our rig as both a display and our home.
Our gen set may be running for 2-3 days non stop and the noise was an issue.