261 forum posts
Got to a stage with my engine before final finishing to attempt a run.
I used an electric drill with an adaptor to drive the flywheel securing wedge which seemed to work well with no shaft/flywheel damage although the wedge was marked.
I screwed the engine to a piece of MDF which was G clamped to the bench.
With the ignition timed for tdc it did a few pops and bangs while I attempted a mixture setup. I found I could only get it to run with the ignition advanced by 30/40 Deg, seemed quite a lot? I was imagining sort of 5/10 Deg?
I also experimented with the lift valve in the carburettor. It is suggested that a 'light spring' be fitted to retain it against it's seat, my interpretation of that it seems was too light as I have given my original a bit of a stretching which it seems it needed.
My setup highlighted the situation that I need to address with the throttle, it was able to move of its own accord while running and I need to secure the engine down better as it shook all the screws out of the base!
Anyway, it runs, some fettling required now!
|Harry Wilkes||02/03/2019 21:56:33|
655 forum posts
Glad it ran video would be nice when your ready
3529 forum posts
Nice one. Yes video would be good. And yes sounds like a lot of advance but if it works, it works. What fuel are you using?
261 forum posts
Been trying different springs in the carb on the lift valve, seems to make a vast alteration in running although it still seems to need plenty of ignition advance.
Only had it running on petrol at the moment albeit about 6 months old!
Seems a lot better for doing a bit of running in and even with my large ring gaps (0.010!) compression appears good.
I shall continue with the trials as I am aiming for a nice slow regular tickover!
Hope this link works to view it running (excuse the mess!)
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