My single cylinder engine

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No the cams are not harden. Do you think it needs to be?

I was always told that automotive cams were 'hard faced'. yet a couple of years ago, when I was building a performance motor for my speedway car, I bought a high dollar brand name cam. The instructions from the manufacturer were very clear that the engine must start straight away on the first start with the new cam, and rpm should be maintained above 3000 for the first 10 minutes.

The explanation given was that the cam needed to work harden on the cam follower contact area and slower RPM would cause shearing and smearing of the cam lobe. It then went on to say the cam followers must be kept in order when the engine was disassembled for any reason, as they would become 'matched' to the cam.

I don't know if the cam had any hardening as supplied, but it obviously becomes harder with operation.
 
You could run it on petrol (gasoline) for a while, just to take the video.

Jim
 
Found Coleman fuel. Will try it tonight.
Luc, no I bought the Flywheel and machine and paint it.
Zephyrin: The flywheel is hold by 4 set screws (grove on the shaft to prevent damage by set screws.)
Aone: When I was away, my wife supper glued the skull and bone :)
 
Hi Borna,
Check Ace Hardware for Coleman fuel.
Regards Gary,
 
You could use petrol (gasoline) for a while. At least to check that it works. And to make a video.:D

Jim
 
Good news is the engine wants to start but the bad news is as its trying to start the flywheel become loose.
I thought 4 set screws will hold the flywheel in placed but I guess I was wrong.
So looks like I got a bad design in placed. Any suggestions that you guys can think of to fix this issue?

This is how the flywheel is hold to crankshaft.

Thanks
Borna

setscrew.JPG
 
Hi Borna,

my two penny worth would be something like this. Have a shoulder for the flywheel to be bolted against. And then use a feather key (or two) with a tight fit to transfer the tourque. However I cannot judge if your design still allows this. You would not want a crack to develop in the corner, so some estimation of the notch factor would be recommended. As well as the required crossection- you wouldnt want to get too thin there. Would be very unpleasant if the flywheel liberates including a piece of shaft...

Cheers, Karsten

shaft_zpsa2db4894.png
 
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Ah- just discovered the other thread in the questions-corner... So it already got sufficiently discussed...
Never mind then...
:hDe:

Cheers, Karsten
 
Hello all,
[ame]http://www.youtube.com/watch?v=rQSRTw5B10Q[/ame]
This is a video of the first run after most of the bugs are out. Since this video I have done some tuning on CAM timing, and ignition timing which now run much better and smother. Today I had it running non-stop for 15 mins until the tank became empty.
Maybe I make another video later on showing it clamp down to a table.


Some modification I made after I was finished.
Shorten the length of the tank for a better fuel delivery.
Originally the flywheel was attached to the crank with 4 set screws. Those became loose as soon as the engine was trying to start. Instead I changed to clamp-on shaft collars screwed to the flywheel.
Added an extension to the cam follower which fixed the problem of getting stocked and was causing the belt to slip.


Original carburetor was very very sensitive. Changed to RC 10 carburetor.

Borna
 
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Very nice Borna. Congratulations on a succesful engine. Again I ask, what part of the world are you in? Obviously, somewhere that there is no snow---you lucky guy!!!---Brian
 
Nice running engine, but isn't this the exact duplicate of Jerry Howell Power house engine? Why do you call it your own design?
 
Congrats on the runner! But man, watch your fingers! I'm getting the heeby-jeeby's seeing you handle the engine like this while running - the open crank and open valve drive, the flywheel with the spokes... Can be all very OUCH!! :eek:

Cheers, Karsten
 
Good point Karsten. I never thought about it. :hDe:
Now to Enginemaker, why are you saying that this is an exact duplicate someone else's engine? Can you refer me to a picture?
 

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