Anyone using an Air Cooled Generator???

[bevans6]

I have a Yamaha EF3000iSEB semi-permanently mounted in the old AC compartment on my MCI.  I'm not hugely sanguine about running it in there while stopped, so I can easily take it out and put it beside the bus, but I do plan to be able to run it on the road if required - haven't yet.  The front wall of the compartment will be ventilated so air can flow in from the front, obviously the entire side of the compartment is open, and I am building a fan driven evacuator to pull hot air from the top of the compartment down and out the existing fan hole.  Air pressure is lower under the bus than in that compartment, but the Yamaha cooling fan exhausts up from the side compartment where the exhaust also exits, so all the heat is concentrated  at one point so a focused cooling fan can have maximum effect.  I also fabricated a remote exhaust for it that exits down through the floor and out along the side of the bus, and wrapped it with fiberglass header tape.  The whole gubbins still gets hot, though.

Brian

[garhawk]

Hi jlink,

General Motors built somewhere near 20,000 motorhomes from 1973 through 1978 with 6kw Onan, enclosed, air cooled generators.  To date, over 8,000 of these units are still on the road.

I have a 1978 Royale with the 6kw Onan which still performs as it should.

[cody]

Garhawk, my 1978 revcon is the oldsmobile sistership to your royale lol.

[zimtok]

I have an air cooled 6.5KW Onan Genset in my 4104.
I run it all the time as we go down the road to run both roof top airs. I think it runs at about 65-75db.
The only problem that I have with it is that it uses a little oil and when it gets a little low it will shut down during a sharp left hand turn because the oil sloshes to the opposite side of the oil pickup..

I have two remote starts, one in the middle of the coach mounted on the wall and one up front on the drivers left side panel.


.

[bigjohnkub]

I use  two honda 3000 air cooled. Will replace with  6000su when building pink bus. Other than that my expierence is the same as Cody's.
  Big john

[busshawg]

I have just installed a 3000 w air cooled into my old A/C condensor compartment. It seem to work well but I am quite concerned about the amount of heat it generates. I did run the exhaust out the side but after running for about an hour it is 140 degrees in the compartment and only approx 65 outside. Therefore I will be also mounting some sort of fan. Don't plan on using too much while parked but for running my A/C while running down the road. It sounds like my set up is similiar to Cody's

[cody]

My a/c compartment has an expanded metal front that has a factory air scoop for air movement, it is also open to the back and side where the engine is and the back hatch, I did fasten a 12 inch exhaust fan to the upper corner of the screened door that is plugged into the generator, when the generator is running the fan is running to exhaust any heat or fume that could possibly build up that might showup.

[4905 doc]

my chink built 5000 watt gen sat in the front bay next to washer. drilled holes in the cargo door and installed a line of round vents. cut some holes under the gen and mounted 12v. twin electric car fans to suck the heat out the bottom. worked fine.

[busshawg]

some good ideas.  I have been thinking the same thing but was unsure of what exactly to do. My floor is also open towards the back but there just doesn't seem to be the air flow. I do have a 12V auto rad fan I could put up against teh mess side screen.

Thanks

[BG6]

Anyone using an air cooled generator to power their A/C units while travelling down the road? I know the water cooled diesel gensets are the best but was just wondering if the air cooled units have ever been used.

You have three issues when using a generator in motion.

First, you need sufficient intake and cooling airflow, and you need the exhaust where the gases won't be drawn into the coach.  Also, you MUST REPEAT MUST have carbon monoxide detectors in appropriate places, including one in every confined area where someone might go, including cargo bays (unless you plan to ventilate them for a few minutes before entering).

Second, you need a generator which can handle the gyroscopic forces in combination with the yaw forces of the coach moving.  Most can.

Third, you need a mount which can absorb those forces.  Again, most can.

The issues are the same for air- or water-cooled -- the only difference is that you can move your heat exchange to another place with water cooling, instead of being forced to cool the genset bay.

The airflow issue can be tricky.  Air blowing past the coach can create a partial vacuum in the genset bay, and in the wrong place can mean the genset doesn't get enough intake air to run.  This is easily solved by putting an air scoop into the airflow.

Also, air going past the bay isn't the same thing as air coming INTO the bay, and the same partial vacuum can cause overheating.  Again, easily solved with an air scoop -- but in cold weather, you can overCOOL an air-cooled engine.

In aircraft, we solve this with adjustable cowl flaps and Cylinder Head Temp gauges.  If the CHTs go up, we open the cowl flap a little, letting more hot air escape, if they are too cool, we close the flaps to trap the heat.

The genset in my coach is an Onan air-cooled unit originally intended for standby power use.  Since these are often in closed buildings, there is ducting to draw the cooling air from outside and dump the exhaust outside.  This makes it easy to control cooling airflow (a simple flap) if I were to set up a scoop.  My genset is in the bay where the aircon condenser was, with one wall which is just expanded metal and a nice, big hole in the floor (you want holes in the floor anywhere that you are using propane, which is heavier than air).

[oldmansax]

We have an gas Onan 6.5 Marquis mounted in the old AC condenser bay. it has the remote start & I built & installed a remote transfer switch. I have a 100 gallon tank I got off  a S&S  RV that was wrecked. Haven't had any problems at all. I have a vertical stack also for when we dry camp a long time. It runs both roof tops all the time.

TOM

[Fredward]

We have a 7k (24hp) twin cylinder Kohler that runs at 1600 rpm or thereabouts. So its relatively quiet. Mounted it in the former condenser bay on our MC-5. It came out of a firetruck and was designed to run in a confined compartment with cooling intake up high and heat discharge down low. Works great and we run it all the time to drive roof top AC driving down the road. Otherwise we use inverter.

No remote start, because I have to manually plug the bus in to the generator when I want to use it. Never installed a transfer switch even though I have one!

Fred

[Van]

I guess I'll come outta the closet too LOL, Honda 5000 In the ac condenser hole,open grill door and to the engine compartment. Been using it quite often during the de-construction of our Eagle, and powers both 1300 roof warts while parked or moving. Lol! my honda is not electric start, but that is nothing a remote switch and a longer cord won't fix  

[Zeroclearance]

What are you folks doing for "bonding"?   What happens when the little neighbor boy hoses down your bus with a garden hose while he is bare feet.

[busron]

We use our air cooled gen, on the road and parked. the guy that installed it put a fan in with it. but the outlet was too close to the intake so it just recycled the hot air, so I installed a duct to have the hot air exhaust out away from the intake and it works great.

Ron