My Onan Generator

Today I totally dismantled the Onan 4000 Gen Set in our RV. I had all the parts laid out so I could put them back together in the correct sequence when the cat showed up and started batting pieces all over the place. Thankfully, it started raining before it got out of control and the cat ran for cover. Being a dedicated Oregonian, I stuck it out and rearranged all the pieces.

The initial problem with the generator was the fuel pump. It didn’t suck very well so I bought a new one. Fortunately, the mounting holes are in the same location so I didn’t have to relocate anything. To test the system, I just hooked it up and got the new one pumping fuel from the tank like it’s supposed to. Unfortunately, that didn’t solve the problem because it still wouldn’t start. I knew I had spark, and fuel was flowing, so the carburetor wasn’t allowing the fuel in. Something was stuck. So, the dismantling began.

To do that I had to remove Diane’s mattress which, unfortunately, got all wet because I laid it out in the driveway. It was in the way. I put a piece of plywood on top of it, but it still got a little ground water on the bottom. Too bad the plastic covering got ripped when I tossed it out there. The plywood was on top of the bracing for the bed so with it out of the way I was able to see the top of the generator containment module. It’s been accessed before because someone cut the top out of it and used about 185 sheet metal screws, and a bunch of caulk, to put it all back together. Removing this allowed access to the faulty carburetor and other pertinent parts that cannot be accessed from the side opening of the generator containment module. I vowed that, when I reassembled it, I would install access doors to take care of that problem.

The carb didn’t cooperate so I threw it away and put on a new 4-barrel Holly, but it still wouldn’t start so I removed the head, took out the pistons, ground the valves, installed new piston rings, added a couple of extrta cylinders so I could fully ustilize the potential of the larger carburetor. It was simple matter of adding an old Kawasaki 750 cc engine I found in the attic over the garage the other day. I don’t know how it got there, but it came in handy.

After I got it all back together I did the “smoke test” and it passed with flying colors. With the addition of the Kawasaki parts the red line bumped up to 11,000 rpm which meant I could comfortably run the unit at 5500 rpm without fear of it falling apart. At that rpm the generator produced approximately 1.7 mega watts of power which is enough to light up a small city. Learning that made me head in a totally different direction.

With all that electricity being generated I thought, “Why not just  yank out the engine and install an electric motor on each wheel?” That turned out to be difficult, but not impossible. I found most of the parts at ACE and the remainder at Wal*Mart. So, now we have a hybrid RV. The very first one ever.

I did a test run to Astoria and back and made it in just over 1.5 hours and it got exactly 72 mpg! And, with no need for an engine or transmission, I added a small hot tub that’s accessible through the old engine cover in the cab. That’s really handy for Diane because when she gets tired of sitting and giving me directions, she can turn her chair and soak her feet. Nice. She doesn’t know about that, yet. It’s a surprise.

With all those kilowatts this rig can do a full 4-wheel burnout and get to 60 mph in just under 9 seconds, and turns a 1/4 mile at 115 mph in 14 seconds. The high end torgue of the electric motors really crank during thos last 5 seconds. They literally scream like little girls. They also smoked a little but I wasn’t worried because they were new and it was just the paint baking off due to the intense heat.

Now I need to shim up the toilet so it doesn’t wobble, install the new horn, and we’re good to go.

I wish I had pictures to share, but I don’t because none of that’s true.

All I managed to do today was get a new fuel pump installed and make it pump gas from the tank. For me, that’s success. Tomorrow, maybe, I’ll tackle the carburetor problem. The hammer didn’t work.

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