Thanks Chris, toprecyler, and Tim it is appreciated.
Here are the parts that make up the driven timing gear and the cam.
And all pressed together.
I mounted the small timing gear and the magnet ring for the hall effect sensor. The magnet ring was one I had made for a different engine but didn't use.
Short day today as I only got the driven timing gear mounted.
It was a fight to get the gear spacing just right and then there was an interference problem with the crank throw bolt and the cam bolt but I persevered.
Each one had to give up a little space.
I made and painted two push rod supports and the adjustable push rod.
I spent the better part of the day working on the intake and exhaust valves. I ended up removing the flapper weight on the intake valve and installing a push spring behind the flapper. The exhaust valve only needed a little more lapping for it to seal.
I don't know exactly what my compression ratio is but from past experience I would say it is around 4 to 1.
I am very happy with that.
I got the throttle done today and temporarily hooked up the ignition system to see if it would fire.
Yes it did fire and try to run but it quickly became clear there were some problems.
The flywheel is just too light without enough inertia to spin the engine over more than 2 compression strokes. It may have started if I had used the drill to turn it over longer but I knew it would always be a problem so a new flywheel is needed.
While I was trying to start the engine I noticed my exhaust valve was not closing. I discovered the push rod was holding the valve open but I had been careful to get the valve lash adjusted correctly before startup. So what was changing? It turned out the cylinder was turning or unscrewing from the support nipple. Just a little turn here will change the valve lash considerably and also cause binding of the piston in the cylinder. I will re thread the base and the nipple tighter and add loc-tite to the threads this time.
I do have a chunk of cast iron I can make the flywheel from so I won't have to order any material.
The trials of a new engine startup.
I did get the new flywheel cut out and painted but forgot the pictures. Tomorrow when the paint is dry I will get some.
Since the flywheel is considerably heaver than the old one there will be increased stresses on the crank shaft.
For the flywheel side I cut a key slot in the crank and broached the tapered bushing. That will hold the flywheel firmly in place.
I had used a rather hard press on the crank throw to the crankshaft but just to give some more strength I added a steel pin and loc-tite.
That should hold that end.
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