Problem with 1990 150 evanrude.

So I've had this boat about a year and a half. Never had a problem starting it but the last three times I've had it out I couldn't get it to run. I thought I had flooded it the first time it happened but it seems to keep happening. It turns over fine and starts to fire enough to stop the starter from engaging. So the last time it did this I took it home and hooked it up to the water hose and after a few tries, got it to run. So this morning I went outside and ran it before going to the lake. It started really quick, it turned over 3 times and fired up. I let it run for about 5 minutes and then drove straight to the lake, about 15 minutes. Got to the lake and same thing. Started to fire and nothing. I thought that maybe I had some bad gas so put some fresh fuel in the empty tank and tried again. Same thing. I ran a compression check about 6 months ago and I was get about 70 lbs on all cylinders. I know I should have closer to 100 lbs but its always ran fine. I was thinking of replacing the spark plus and fuel filter, but I'm afraid I need to rebuild the motor. Any ideas would be greatly appreciated.

You most likely have a carb problem. When starting in the lake you have back pressure that makes the fuel mixture more rich. Look for fuel dripping in the carbs or could be the enrichment solenoid leaking by. Old or incorrect sparkplugs can contribute to flooding.

Gary, I'll give that a try. Thank you!