Rupnow i.c. Engine with governor

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Thanks for the info but still cant picture it in my head:confused:

Thanks for the ball turner I'll try to make a good use of it

hopefully I'll be back on my engine next week early I walk beside it everyday
and tell him not to cryRof}Rof}
 
Aha!!! I must have lived right, and got the magnet in the correct way. The Hall effect does get triggered by the magnet when I turn the engine over, and I get a big fat spark!!!
 
Okay, Guys--I have a bit more knowledge to share on this CDI business. Having read through all of the information on the CD that came with the kit, I have seen the warning repeated numerous times, to NOT ENERGIZE THE HALL EFFECT SENSOR UNLESS THE SPARK HAS A GOOD PATH TO GROUND OR IT WILL FRY THE HALL EFFECT SENSOR AND POSSIBLY THE CDI. Now ya can color me dumb, but I was a bit concerned. The magnet is embedded in the aluminum disc, and the Hall effect sensor is epoxied into place---does this mean I can't even turn my engine over? I was concerned enough that I sent Roy Sholl an email and asked him. Okay---So I was dumb!!! The warning only applies if the power is on. I kind of suspected this, but I wasn't sure, and I have seen a lot of posts about people inadvertently burning out their hall effect sensors. Better to be a bit dumb and ask than burn something out before I even got to use it.
 
I just got home 2 hours ago from a 3 day marathon with wife and two grand daughters. Went to see a live production of "Mary Poppins" at the theater in Grand Bend, Ontario, on the shore of Lake Huron, stayed overnight in London, Ontario, then on to a day at Niagara Falls, spent walking about 300 miles at Marineland, then a ride on the "Maid of the Mist". Grand daughters enjoyed every minute of it, but I had to lay down for a one hour nap as son as I got home!!! I got up from my nap and took the "Rupnow Engine" out to the test bench, with the new CDI hooked up on it. I took my camera with me "just in case" and turned on the fuel and give it a flip. Engine took off and ran like gangbusters as can be seen in the video. So what does this prove??---Well really, absolutely nothing, other than the fact that the engine will run with old style points or with CDI ignition. The sparkplug doesn't care where it gets its spark, as long as it gets it!!! Now on both of the videos I have posted, running with and without the CDI, the engine has stopped of its own accord. I didn't shut it of. It just up and died, right in the middle of the video. My focus now will be to "tune and tamper", until the engine can set there and run all day, until I shut it off. I will keep you posted as I make continuing progress, but I knew you would be interested in seeing this.---Brian
 
ALRIGHT!!! WE HAVE 20 MINUTE SUSTAINED RUN!!! Ever since I built this engine, it has behaved as though it was overcarbureted. I built a smaller bore carburetor last week, and tried it on the engine, but didn't see any real difference so I took it off again. The biggest "tell-tale" of an overcarburated engine, is that they are chronically starved for gas. They respond very well to "finger over the air intake" choking, but as soon as it burns the extra gas that was brought in by choking, they stall out and have to be choked again.--and they are very easy to "over-choke" and flood. A smaller bore carb works better because the air has to flow much faster thru a carb with a small "throat" to fill the cylinder when the piston travels from top dead center to bottom dead center. This faster air flow creates more venturi effect at the fuel orifice, and consequently sucks up more fuel, so there is a higher fuel to air ratio than on a large carburetor. They require less manual choking, and consequently are less prone to flooding issues. The reason that it didn't solve my problem last week was, as I suspected, the 12 volt coil I was using was giving intermittent spark. Once I got the CDI on the engine, and the smaller carb, it fired right up and ran for 20 minutes until I shut it off. I am going to post the drawings of the smaller bore carb right now, and the video of the sustained run. I now consider this engine t be a complete success, and will wait anxiously to see some of the other Rupnow Engines that are being built come to life.---Brian Rupnow
 
Runs great Brian, I'm about to order my CDI ignition and some spark plugs. I may get it running without the governor first, then carry on making the rest. I might use the bevel gears that I made in the past, their about the right size. The project that I have in mind for them is a long way in the future, so I can make another set later.

Paul.
 
Congrats Brian. My single biggest worry with this build is the carby. I haven't looked at the drawings at all yet, but I'm concerned about my ability to make it. I'll likely leave it til I've done everything else then cross my fingers and go for it.
 
Congrats Brian. My single biggest worry with this build is the carby. I haven't looked at the drawings at all yet, but I'm concerned about my ability to make it. I'll likely leave it til I've done everything else then cross my fingers and go for it.
Cogsy--It took me less than a day to build the small carburetor. The biggest trick is getting the fuel inlet tube and the needle valve tube lined up to solder them. I recommend making up a one time jig to hold everything in alignment to solder them.---Brian
 
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Brian, it was nice to meet you up at the gas and steam show.

Thanks for all you work on this engine. I am going to attempt to build one this winter.

Cheers,

Tom
 
Brian, it was nice to meet you up at the gas and steam show.

Thanks for all you work on this engine. I am going to attempt to build one this winter.

Cheers,

Tom
And it was very nice to meet you Tom.--Its always nice to be able to put a face with the different members I correspond with.---Brian
 
So, this is it. I have found that I CAN adjust the speed when the engine is running by turning the governor spring tension knob to put more or less pressure on the compression spring. The more the engine runs, the better it runs. It is a noisy devil, mainly because of the meshing of the 45 degree bevel gears. This is the last video I will post unless I change something on the engine.
 
Pat--I feel really good about this. Even though I felt very confident about being able to design a new/different engine, it was a great leap of faith to ask 10 other folks from around the world to join me, before I had even proven my design. There were a couple of times when I had that "Oh God, what have I done??" feeling, especially when I was getting the intermittent firing from the old 12 volt coil, which is very difficult to diagnose. That was the main reason that I went to the CDI ignition.--In general, it either works or else it doesn't work, making it a lot easier to diagnose why an engine won't run consistently. The download link I have posted to the drawings will get the water cooled version, the air cooled version, the version with ignition points, or the version with CDI ignition. The engine is out in my main garage, running away like a trooper, as it has been for the last two hours. This is a happy ending to a summer long story. I expect I will see a lot more "Rupnow engines" built, now that the design has proven to be a success, and the drawings are all free. ----Brian
 
I just ordered three 5/8" diameter aluminum balls off e-bay for an outrageous price. They are selling them in lots of 3 and they are tapped 1/4"-20 thru. I don't see the 1/4"-20 thread as being a problem, I will probably fill the threaded hole with JB Weld and then put in a counterbored hole for a #5 shcs. I may paint the balls with some flat finish paint, as there are really weird reflections off the array as it spins, which make it look like its kind of lop sided. (Its not---if I block the light source with my hand, then the array is very consistent in form.) The engine is running so good now, I can't leave it alone. My wife wants to know why I keep disappearing out of the living room and going downstairs to the main garage and running "That noisy thing!!!"
 
Incredible work Brian. It took lots of Cojones to do what you did. Congratulations.

I'd have gone along for the build but I'm starting my first IC and I'm looking at a year + project. When I'm done maybe I'll start on your design.

Phil
 
Philjoe--The people with the cojones are the ones who jumped on the bandwagon and started to build the "Rupnow Engine" before anyone knew whether it would actually run or not. I don't think I would have done that myself.
 
Brian,
Given your rep for building things that WILL work, I'd say sure the builders were taking a chance, but the odds were good you'd fix any problems along the way - which you did. Nicely done.

Have you run through a tank of gas yet:D?

Cheers,
Phil
 
Be careful Brian that your wife doesn't get jealous of the engine, got to spend some time with her as well.;)

Paul.
 
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