MikeSell

My Feedback: (2)

I found a Snapper snow thrower whose engine seems in good shape. Tecumseh says the engine weighs 12 lbs but quite a bit of that weight is the steel recoil start mechanism. The engine itself is quite compact. The flywheel is quite a large diameter to allow teeth for the electric starter. I am looking for a way to use the CDI ignition with a smaller flywheel still retain function and rebalance. Any suggestions? (I have my own machine shop.)

ANeat

My Feedback: (15)

Well if the motor is internally balanced you should be able to remove the flywheel completly and run a C&H ignition. Also you could fabricate a mount and use a smaller flywheel and coil off of any chainsaw/weedeater. Im sure someone on here has a spare.

Of course if they are using the flywheel as part of the crank counterweight (externally balanced) you may want to look elsewhere for a motor.
If you can, post some pics of this beast, Im sure we would all like to see it
If you get the motor stripped down put it on a scale and get an actual weight.

Machine shop eh?? Got any CNC equipment??

Adam

bdtsr

My Feedback: (5)

MikeSell, I am currently working on the 138cc version and the 49cc versions of these Tecumseh engines. Go with electronic ignition on anything larger than 50cc due to kickback. I should have most of my components in late this week and be putting things together next week. My 138 started at 24lbs! I'm down to 8lbs now. My 49 started at 6lbs and is down to 3lbs now with still having to cut the shaft off the back. These engines lend themselves to easy mounting because of the bolt holes on the back of the block. Mufflers will be another story.

ANeat

My Feedback: (15)

If you guys need mufflers or headers let me know. Ive done some custom stuff already and have a tubing bender and tig welder.
If Mikesell hapens to have some CNC equipment to mill out the flanges that would help a lot. Ive got a small lathe/mill but its all manual so if it takes a while sometimes to carve out things.

Bdster; 8 lbs for a 138cc :stupid: sounds pretty good to me. Is that a single cylinder??
Adam

bdtsr

My Feedback: (5)

Adam, Yes it's a single. This weight is without muffler, carb, ignition and prop hub. I still have some more excess metal removal to do though. My target weight is 8.25lbs complete. This is in the ball park of most 140 to 150 cc engines. I may just be contacting you about a muffler for this beast if it seems to do what I want (28X10 prop at 6400rpm). This is about the only way I can afford to do some larger planes (90" and up). My 49cc cost me $35 delivered and has never seen fuel. My 138cc cost me $100 delivered and also has never seen fuel. They are also available online at various places for cheap prices. They also sport ball bearing supported cranks.

ANeat

My Feedback: (15)

Those sound like good prices for sure. You will have to share it with us where you are getting these deals Ive made up a few header/muffler combos for myself and a few friends and have had some good results at quieting the motors down without loosing to much power. Its another part of the hobby I enjoy.

Ive got a couple pics in my gallery if you want to check it out.

Adam

bdtsr

My Feedback: (5)

I really didn't want to jump the gun here on these engines. Without anyone else doing them, I didn't have any guidance or info. Ralph Cunningham (RCIGN1) has helped and is making up the ignitions for me. These engines may not work well for rc and no sense in getting to excited just yet. If they work well then we'll hook up for the mufflers and I can provide info that I've found so far!

ANeat

My Feedback: (15)

Sounds good; Lead the way.
Adam

bdtsr

My Feedback: (5)

Well I have a 98cc Tecumseh on the way! So, MikeSell, how is yours coming? I should have mine by next Friday. I'm shooting for 6lbs on this one. This one will have a gas tank as well. I'm going to try and run it stock with a prop on the output shaft and see what it will do. I'll keep everyone posted.
Brian

MikeSell

My Feedback: (2)

Sorry guys, I have a son graduating and an open house to put on. Three planes are nearing build completion and I still don't have the maiden flights on two completed planes and I haven't had opportunity to fly another I finished.
I did remove the engine and tank from the snow thrower and made plans but have not had a chance to act on them. The flywheel has to be part of the balancing design. It is large and bell shaped but would fit within the cowl of an appropriately sized radial design.
CNC equipment? In my home shop just a mill, lathe, band saws, drill presses etc. all manual. I have access to a machine shop at a local college with both manual and CNC mills and lathes. I work at a big 3 auto plant in the machine shop area as a diemaker.
The plane for that engine might have to wait. I still have (2) 38cc (1) 41cc (1)31cc (1)28cc all converted waiting for airframes.

geardaddy

My Feedback: (27)

have some new flywheels from 62 cc saws with coils that can be fitted to a engine with some ingenuity.

rsieminski

What kind of rpm/prop numbers are you getting with these 90-100cc engines, and what's the rtf weight? This might be exactly what I need.
Thanks,
--Rick