Generator quieting

jjrbus wrote:
After a little bit of experimentation with cardboard and masking tape, I have used a roll of tape and all the cardboard in the neighborhood. the Jauguston design runs too hot for my comfort zone, unless his 2000° insulation is somehow dissipating heat in a way that I do not understand.

I can easily get an ambient air temp in the 90's in the gen box at the inlet side of the generator, the exhaust end at the separating wall, on the "cool" side of the wall will quickly rise to 120° (temp measured at base of handle on exhaust end) without the fan assist in any ducting resembling Jauguston's. The temp in that area will drop to a few degrees above ambient when genset is taken out of box.

Also in my tinkering if I route the engine exhaust separate from the cooling air the temp of the gen set goes up. That has me completely baffled??

After experimenting with this for a few hours it is obvious that your adaptation of this design does not have this issue. Your exhaust end will only be a few degrees warmer than the inlet temps as you are not restricting airflow. Any restriction to the exhaust airflow quickly raises the case temp of the genset. If you have the opportunity the temps on yours would interest me.

Unfortunately I wouldn't now be able to provide any temp measurements as I sold my EU2000i a few months ago and the purchaser was so impressed with the quiet box after I demoed it he bought it too. :B That said, jaguston built his EU1000i quiet box back in 2007 and as discussed in this thread he did take temp measurements and found no issues at all. I discoursed with him myself in early 2015 by which time he had used his quiet box countless times and had had no temperature issues with it at all. The key, as I've detailed previously, is to take advantage of Honda's EU generator design in which both hot exhaust gas and hot cooling air are exhausted together and are prevented from mixing with cool intake air. Jauguston's design achieves that goal by sealing tightly against the generator's plastic exhaust bezel, as he described (in part) to me in this PM ...

"I'll try to describe how it works. The EU series take in cooling air from several vents on the sides near the end the control panel is on. All the exhausted cooling air and the engine exhaust comes out through a grille on the opposite end. You may see the foam donut on the bulkhead near the back of the box with a hole in the bulkhead inside of the donut. The donut presses against the outlet end of the generator around the outlet grill. This arrangement prevents heated cooling air and engine exhaust from looping back to be taken back in to the cooling air intakes. This process is what makes the whole system work using only the generators cooling fan to keep it cool without additional fans. The outlet air/exhaust then goes through a three pass down/up/down then up again maze finally exiting the box vertically up. I placed a 6" square piece of high temperature pipe wrap on the bulkhead opposite the engine exhaust outlet just behind it to protect the 1/4" plywood divider from the heat of the exhaust.

There is a 4" X 4" hinged door to access the start cord and on/off switch and another to access the idle switch. I put a duplex 120v household electrical outlet on the end of the box the control panel is and put a short (12") cord with a plug to connect to the generator. I screwed some plastic things that are made to cap square steel tube to the bottom for the feet to fit in I found in a hardware store. The size that fit over the feet of the generator. They have sides maybe 1/4" high. Their purpose is to keep the generator against the foam seal. Most anything that keeps the generator firmly against the foam seal would work.

I lined the box with 1" sound deading material purchased from reddenmarine.com ... it is commonly used to line the inside of yacht engine rooms. The sheets are about $80.00 for a aprox 34X50 some inches. Its fairly heavy. The box weighs about 28#."

My design was simply a budget based interpretation of jaguston's design and like he I experienced no overheating issues.