Thoughts on engine selections......

[Chris In Milwaukee]

Once it’s moving and warm, it’s smooth. First 30 seconds or so when it’s really cold it’s shaky, and shutdown of course. But I would like to get a dynamic balance. But it did prompt the question if there’s a counterbalanced 360.

[Chris In Milwaukee]

Once it’s moving and warm, it’s smooth. First 30 seconds or so when it’s really cold it’s shaky, and shutdown of course. But I would like to get a dynamic balance. But it did prompt the question if there’s a counterbalanced 360.

Turns out this was an ignorant question on my part. I had the wrong idea about why counterweights are used. Here’s a good explanation. Apologies for the distraction!

http://www.vansairforce.com/community/showthread.php?t=119138

[Bdflies]

Not an ignorant question at all. It prompted curiosity and led to shared knowledge!

If your O-360 is that rough, on startup, I'd really take a hard look at the spark plugs and maybe the wires. When the plugs get fouled or gaps widen a bit, mis firing appears as roughness.

Bill

[Chris In Milwaukee]

Annual found 6 out-of-spec plugs and mags a few degrees out. I’m sure I’ll have a “new plane” in a couple of weeks when the exhaust rebuild gets back!

[Nev]

Turns out the flywheel had a couple bolts and nuts from a previously undocumented static balance on a past prop.... found a cracked exhaust flange, and one additional crack and a missing tail pipe clamp at the muffler. The big find was the gookumpucky the A&P/AI used between the cylinder base flange and crank case....and quite a few under torqued cylinder base nuts.

Mark were there any downstream effects on your engine from the goop you found on the cylinder flanges ? Where did you source your engine ?

I've also found contamination on my cylinder flanges that has led to the failure of 3 cylinder studs HERE. I had purchased it (rebuilt) from a supplier recommended on this forum.