Let me preface this by saying I know very little about outboards, but have worked on inboards pretty extensively. I recently acquired a Johnson 8hp 2 stroke for pretty cheap. I threw it on my jon boat and it had very low power, but had no problems starting or idling. I got home and did a compression test and the cylinders were about 75 and 70 hp. I thought that was pretty low so I put a new head gasket, exhaust cover gasket, and water/cooling cover thingy(?) gasket. the tops of the pistons and the cylinder had quite a bit of carbon buildup so I spent a little while cleaning that up. Cleaned fuel pump, which looked brand new. I also took the lower unit off and put a new impeller on, the old turned out to be falling apart. The guy i got it from said the carburetor was just rebuilt and it looks pretty clean, But I dont know anything about these kinds of carbs.
Did another compression test and its basically the same. Some folks online are saying that smaller 2 stroke engines dont have those high compression values like larger engines. Is this true? If the compression is okay, what else could cause low power? I haven't been able to get it back on the water since doing all this, but does anyone have any ideas?
thank you in advance
Did another compression test and its basically the same. Some folks online are saying that smaller 2 stroke engines dont have those high compression values like larger engines. Is this true? If the compression is okay, what else could cause low power? I haven't been able to get it back on the water since doing all this, but does anyone have any ideas?
thank you in advance
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