2008-04-04 jtodd@loligo.com
Main page: http://www.loligo.com/projects/changfa/
Movie: Movie of engine (Warning: movie is 70mb)
Changfa 195 Diesel Generator project
So, it's taken me a while to get back to work on this - the big Lister CS project along with other things have kept me away from backyard tinkering with the Changfa.
I got all the electrical stuff wired up yesterday, and fired it up this morning with the generator connected to something - what a concept! The first run (see video "Changfa-start-run.mov") with the ST-10 hooked up went fine, and I even nailed the 1800 RPM/60hz spot without having to adjust at all! Lucky first break. The engine doesn't smoke, runs at 195F on the nose and the bottom of the radiator is cool, and the whole rig doesn't have any serious vibration.
In the video, you can see me doing tests with a sound (dB) meter. The engine is louder than practical in a semi-urban environment, even with the muffler on it. I think that most of the noise now is being transmitted out of the casing of the engine and valvetrain and is not coming out of the muffler, though I'm sure I could drop another 10dB off the muffler outlet with a better trap. Also, a lot of sound is coming out of the air intake even though I've got a sound-deadening intake/filter on it already. Maybe another 5-gallon pail with fiberglass batting or noise pyramid sheeting will do the trick.
If I could build a shed for this which had a concrete floor and could be lined with some serious sound panelling, perhaps it would work. Alternately, I could dig a pit for it, cinder-block and plastic line and perhaps some concrete for walls and floor... but that's getting a bit carried away.
Left to do: get the lower "utility" tray installed for battery, etc. and get the starter wired up so I don't have to hand-crank this monster. Maybe build some sort of relay to auto-actuate the release valve during starting.
2008-02-07
So I've about finished with the "big" parts of my Changfa 195 side project. I've got an ST-10 mated to it (adaptor and cooling plate from George at utterpower.com) and a cooling system that works great.
I put two holes in the sides of the frame rails, and I then slide big iron bars through the holes and lift the whole assembly via an engine hoist using an engine/transmission tilter. Getting it to balance side to side is a bit of a chore, since I forgot that the engine weighs quite a bit more on one side. However, shortening up the chain on the heavier side by one link solves that problem. The frame has two sets of holes for the engine - one laterally (the current installation orientation) and one horizontally, in case I ever get some equipment that runs on belts, like a pump or a DC generator that doesn't need to be directly-coupled. It was easy enough to drill the holes when it was being built; why not think ahead a bit?
There are small anti-vibration pads bolted to each corner. Even still, it shakes the house a bit running it in the garage downstairs. The temperature gets up to about 190F as a steady-state, since the thermostat is a 195F model, and the thermosiphon runs along just great. The water is much cooler when it gets out of the radiator - the tilt of the radiator allows airflow, and the spinning flywheel creates a bit of a breeze. It never gets too hot here in Oregon, so I suspect it'll never be a problem. Slight leakage around the thermostat weld, but I'll fix that with some RTV. This is a zero-pressure system, so I'm not too concerned about much leakage.
I'm going to shorten the radiator frame, since it's about 1.5 feet too tall to be moved around in the garage easily. I may or may not mount a bigger fuel tank on the radiator frame and do away with the existing tank. The tank that's on there is a bit too wobbly and I can hear a noticable change in noise volume when I put my weight down on it an prevent it from rattling.
The powder coat came out well, and I'm surprised I haven't dinged it up with mounting the radiator, engine, and generator.
What's left? Getting the electrics connected to the ST-10. I'll have a pedestal that bolts onto the frame. I need to get a piece of board (or maybe galvanized extruded mesh with supports?) to put into the frame rails underneath, and then a battery to mount on that. Then a starter button circuit so I can use the starter. I think a more muffled exhaust will also be in order. It's too loud right now with the stock can. I might also make some sort of mini-canopy for it, to keep rain off it in those rare cases when it's outside (which, the more I think about it, will probably be most of the time that I use it, since this will be the "emergency bad weather" generator.)
http://www.loligo.com/lister/changfa/pictures/