2000 Mercury 75hp stalling

[Calhouncm]

Hello,

I have a 2000 mercury 75hp 2 stroke. I just bought the boat about a month ago. Took it out for its first run, about a half mile away from the dock it lost power and quit, skipped a little and quit. It would fire some turning it back over and just quit again. I used the trolling motor to make it back in.

The ignition switch wasn’t the smoothest so I changed that out to eliminate issues with it. Took my next test ride tonight. Same problem...

After making it to the dock, loading, then heading home it was around 20 minutes later. I checked compression and had around 125 lbs compression on all 3 cylinders. The spark plugs which are buhw-2 were all a little wet when I took them out. I used a spark tester on all 3 and they all seemed to have a good spark.

I have plenty of gas in the tank. The tank is built in to the boat and is vented. I tried taking the gas cap off to make sure that wasn’t a problem, but it didn’t help.

im debating just bringing it to a shop as I don’t have a lot of time to tinker and retest, but figured I would ask and see if anyone had some good ideas?

 

[Texasmark]

Not much to go on with where it was when the PO finished using it. To quit and fire again sends me to fuel problems. Fuel problems take me to fuel line replacements in the feed to the engine from the tank including a new squeeze bulb, possible fuel pump (engine) in need of new kit.

First I'd remove the fuel line from the engine...assume just a hose barb at the engine. Remove the clamp and pull or cut the line off the barb to get access to raw fuel from the tank. Get a container and using the squeeze bulb, squeeze some fuel into a clear container and examine it for brown flakes. If you see them there you will have them in your fuel pump, internal fuel lines, and surely the fuel filter.

If all that checks out, reconnect the fuel line to the engine. Remove the hose at the outlet of the internal fuel filter, easily seen from the port side of the engine. Using the squeeze bulb, force fuel into the clear container again and examine it and observe good fuel flow as you pump. Take a cotton swab and swab the inside of the hose you removed from the filter outlet and if the swab comes out with little black particles, that's engine fuel line degradation requiring new internal fuel lines, and filter and while you are at it fuel pump kit and carb kits......I had a 2002 90, same engine couple of years later and bit more hp. You can see my trail of fuel related problems on an ethanol engine of that age.