All this talk of weak spark got me thinking again about my 20B. It has the stock CAS. I have found that the spark is weak and sometimes intermittent when cranking. When I noted this, I was sure something was wrong. I then checked using the Mode 8, and the spark was great. It would start and run, so I forgot about it. The engine always started and runs fine, but I have noticed more recently on cold mornings (meaning about 40F here in SoCal) that the starting was a little more hesitant, and would fire intermittently for a bit before getting going.
I recall when we were checking timing on the dyno, it would not fire the timing light consistently – figured it was the light. On recent flights, on two occasions, after steady cruise for ½ hour or so; there was a very short duration power sag; just a second or two and then back to normal. No roughness; just some power loss that gets your attention, and then it’s OK. I’m burning unleaded mogas, so shouldn’t be the famous S.A.G. others have experienced. I have no explanation.
These things, taken together, make me wonder if I’m really getting the strong spark I should be getting. I know that during cranking it is barely enough to fire the plugs. I haven’t checked it when running cuz it’s a little difficult to hold a wire off and see how far the spark will jump when that prop is going right there. But I guess I need to make a check of that.
What sort of cranking spark should be expected? Other ideas on what to check? Is it something about the EC2 and the CAS?
Al
Subject: [FlyRotary] flooding
I made it out to the airport today, soldered up the CAS and installed it. Before I cranked it over, I put it in mode 8 and fired it off. The usual nice blue sparks. Then set it to mode 0 and cranked with the plugs out and pumps/inj off. No spark. Cranked and looked again. Every so often there would be a weak spark or 3, but most of the time, nothing. So little or no spark