Open Column Twin IC Engine - Finally, completely finished!

Great job on your engine Chuck. It has a great two cylinder sound. How long will it run under a load like that before it gets too hot?
gbritnell

Thanks, everyone, for the compliments and comments. I really enjoy hearing from all you guys.

kuhncw said:

Nice job, Chuck. Your twin runs and sounds great. You told me before, you are waste firing the engine. Are you using a Hall effect system? What sort of coil or ignition setup are you using?

Chuck Kuhn

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Chuck, the coil was bought from Jerry Howell a number of years ago. It has two secondary leads that both fire at once and I think the name of the coil was Exciter. I'm just using points and condenser for the ignition. The cam for the points sits on the camshaft opposite the timing gear and has two flats positioned at 90 degrees to each other. It's powered by a small, 4.8 volt rechargeable battery.

petertha said:

Congrats, nice engine!

- what kind of spark plugs & ignition system is used?

- I'm intrigued by your motor/light bulb 'illuminating dyno' ;D . Is it really as simple as hooking up a DC motor kind of in reverse? I realize it's just ticking over & not full throtlle, but in principle, if it's powering a 60 watt load, would that be equivalent to (hmm check my math..) 0.08 hp at that rpm?

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The spark plugs are CM6 plugs with a 10mm thread. They are about the smallest plugs for commercial use you can buy and are readily available at around $3 each, unlike the smaller .25" x 32 tpi thread spark plugs usually used in model engines which cost around $18 each.

Yes, you can use any DC motor which has permanent magnets as a genertor. If it has brushes, it will produce DC current. If you use a stepper motor or one of the newer brushless DC motors, it will produce multiphase AC power.

gbritnell said:

Great job on your engine Chuck. It has a great two cylinder sound. How long will it run under a load like that before it gets too hot?
gbritnell

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George, It's never gotten over about 210 deg F even though I've run it for 10 minutes or so. I suppose it probably would if I ran it long enough. Guess I could just replace the light bulb with a DC fan pointed at the motor, but it has a pretty small gas tank and would run out of gas after about 15 minutes anyway.

Chuck

Chuck,

Gotta say another great job. I also like the sound. It's nice to see the generator and light bulb so we can see it working under load.

Where do you get all those 90-Volt DC motors?

--ShopShoe

Chuck

It did occur to me that you should consider rigging the motor/generator as the starter as well and make it self contained. Even recharge the battery. (12v motor though)

Pete

You have raised the bar once again. I especially like that the engine has some work to do. I hate it when a capable engine is collecting unemployment compensation.
Alan

ShopShoe said:

Chuck,

Gotta say another great job. I also like the sound. It's nice to see the generator and light bulb so we can see it working under load.

Where do you get all those 90-Volt DC motors?

--ShopShoe

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Thanks, ShopShoe. I have several DC motors. Some I bought from The Surplus Center in Lincoln Nebaska a number of years ago. I've also bought them on eBay and a salvage store in Phoenix when I lived there. These days, I think eBay and/or Surplus Center are the best choices.

doubletop said:

Chuck

It did occur to me that you should consider rigging the motor/generator as the starter as well and make it self contained. Even recharge the battery. (12v motor though)

Pete

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Yeah, I could just pull out the bulb and put 90 volts DC across the DC motor and it would act as a starter for the engine. Unfortunately, 90 volts DC is a little hard to come by without such things as variacs and bridge rectifiers.

Chuck

Think of it as another challenge, you'd proably get away with your 110V just rectified and for a short burst (a bit scary though). Or go down to something a with a bit lower voltage

Actually just leave it as it is, it is really great. Now you can get on with your steam vehicle.

Pete

Chuck,

Great job on your engine. Has an eye appealing look and is very ear appealing too. Sounds very much like my JD 420. I've a horizontal 2 cylinder that needs finishing and the valve train setup on your engine may be the ticket. Could you elaborate on the setup and maybe post a few closeups.

Thanks,

Craig

Very nice Chuck. I love the sound the odd firing gives, especially under load. Dave

Another great engine,Chuck, and sounds even better under load. How do you lubricate the big ends though? are they plain or ball bearings Chuck?
Stew

CMS said:

Chuck,

Great job on your engine. Has an eye appealing look and is very ear appealing too. Sounds very much like my JD 420. I've a horizontal 2 cylinder that needs finishing and the valve train setup on your engine may be the ticket. Could you elaborate on the setup and maybe post a few closeups.

Thanks,
Craig

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Thanks, Craig. Here is a link to the original build thread which has some closeups of the valves, rocker arms, etc.

http://www.homemodelenginemachinist.com/index.php?topic=711.15

compspecial said:

Another great engine,Chuck, and sounds even better under load. How do you lubricate the big ends though? are they plain or ball bearings Chuck?
Stew

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Thanks, Stew. The crankshaft mains are bronze bushings. Everthing on the lower end, including the cam and lifters, get lubricated with an occasional squirt from the oil can. I use 90 weight compressor oil or chainsaw bar oil which seems to be pretty sticky and lasts a long time.

Chuck

Nice job Mr Fellows! She looks and runs great.