The two engines arrived and I had them both running withing 15mins, 5 of which was sorting out suitable adaptors for the air supply.
However I may have spoken too soon🤐🤐🤐🤐 After getting the G1 to run and thinking my work was done it started to misbehave. It would run OK for a while then the speed would go up and down before it stopped rotating and just oscillated back and forth.
The cam position was adjusted a few times from below but it still happened as if stopped from oscillating I could hear air still flowing out the exhaust at BDC even if the cam was nowhere near the open position.
Off with the head to have a look at the valve. It did not look like it was really closing and a could feel it was in contact with the base circ;le of the cam if not actually lifting so 5thou was taken off the end of the valve stem and put it back together for another try.
Same again so another strip down and I thought the valve was sticking a bit, though hard to tell as the spring is held down by the head. Out with the Mic and the bottom of the stem is 0.127″ compared with 0.124″ just under the head so into the lathe and Emery it down parallel and put the engine back together.
Same again. Off with the head once more and the valve did not seem to be sitting down so my thoughts turned to the tappet that I could not see. So off with the flywheel, Big end cap off so the piston could be pulled, loosen cam and slide out the crankshaft. The tappet dropped out.
On closer inspection the top of the tappet is threaded for a push rod and there is a lock nut. This nut was loose!! Which was allowing the valve lift to alter while the engine was running and when the lift became too high air was passing all the time.
I reset the pushrod length and locked up the nut before putting the engine back together.
All seems to be running as it should now.
Will take a better video over the weekend as the base plate still has to go back onto the bottom of the crankcase.
