No crank/no start (sort of)

My 25hp yama had been running, then one day battery was toast. Replaced same, all good.
a couple of weeks later, battery was low again, but it ran fine
last week, began to run rough, hard start when warm, stalling when going from higher speed to idle. Then crank/no start or hard start.
Today I put a charger on battery and checked compression (~170-190), new plugs2 days ago looked good. Put plugs in and started. It then stalled, and when I tried to restart had no crank/no start. No electric choke op, etc. checked fuses, ok. Pull started ok, but still ran like crap. What do I chase for no crank?
new member with some outboard repair history.

Sounds like you're dealing with issues from 2 separate systems...electrical and fuel. Definitely need to troubleshoot electrical first, if you choose to continue to use electric starter. Pull-start engines don't need a battery, so you could go about troubleshooting that way by isolating one system issue at a time. Regardless to your approach, these 2 systems don't overlap...either you've got an issue with electric, issue with fuel, or issue with both. Be that as it may, troubleshooting is specific to the system. Does that make sense?

classic a, thanks for the response. I know I’ve got two issues but I’m trying to find where to look for the starting issue as I’ve just had shoulder surgery. Also I didn’t know if I could have fried an electric component when I had a charger on the battery at the same time the engine started. Start problem began immediately after that. No crank or electric choke ops.

Ericthered said:

classic a, thanks for the response. I know I’ve got two issues but I’m trying to find where to look for the starting issue as I’ve just had shoulder surgery. Also I didn’t know if I could have fried an electric component when I had a charger on the battery at the same time the engine started. Start problem began immediately after that. No crank or electric choke ops.

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How do your battery terminals look? Have you cleaned them lately? If so, how does the connection on the battery cable look? if it's cracked and has been exposed to seawater, I'd recommend you reterminate the cables with new connectors.

Agree with ClassicAQ - work one issue at a time to the end.