Re-Break In DA 50

[Stainless Skills]

About a month ago I got my engine back from DA. They fixed it because the cylinder blew off the crankcase right after break in. The engine came back free of charge with a new piston head, ring and some other small replacements. The needles are set from the factory and I am using a stock DA muffler with a Vess 22A. An equivalent loading prop would probably be a 22X8.

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I ran the engine this afternoon for about 3 minutes with a Lawn Boy 32:1 mix in some 89 octane gas. The reason I am not using 87 is because I thought that I heard a slight pinging right before the cylinder blew off the crankcase before. Is this gas fine?

The engine, set from factory, ran great; the transition from idle to full was very quick. I got 7000 rpm on the ground with the Vess 22A. Is this too high of an rpm reading? Do you think the high end might be a little too lean? This reading was taken after the engine had been running for about 2 minutes and was pretty warm. The reason I ask this is that after I shut the engine off there seemed to be a lot of play when I spun the prop. I could rotate the prop shaft back and forth quickly in my hand and there seemed to be a clicking, like some bolt was too small for the hole it was in. I could move the prop back and forth in my hand and it seemed very loose for a couple of degrees –there was no resistance as if the piston would not move up and down in the crankcase when the prop shaft was moved slightly, maybe 5 degrees. When the engine cooled off it was back to the way it was. Is this normal, there are no black oil streaks on the side where the cylinder meats the crankcase. The engine seemed very hot but it is a gas engine and I know they do get hot.

The engine transitioned great from idle but it has a problem idling. When the engine idles it does so consistently for about 7 seconds and then begins to loose rpm very gradually. If I leave the throttle maybe a fifth above idle it sits at that rpm till the cows come home but when I bring the stick back to idle and let the rpm settle at around 1900 it slowly begins to loose rpm. I did this and waited about 15-30 seconds, by then the engine was hovering around 1600 and getting ready to drop below that and I was afraid it would shut off so throttled back up.

Before I had the engine blow up on me I probably fiddled with the needles for a good 2 hours at different times to try and figure out how to get my idle to stay consistent. Is there a procedure for correct idle that I can follow?

Thanks a bunch for your help.