I bought a boat last year (my first one), but I've been around boats for 17 years. It has a rebuilt 150 Merc OB. At the end of the year the last two times I took it out it would die when I got the boat going over 4000 RPM. It would start back up after a minute or two. Got it back in the water this year, took it out and it died again. I was thinking it was a fuel issue, since I didn't get an overheating or oil pressure warning from the "horn." I couldn't get it restarted for about 5 minutes. I took it to a mechanic and it looks like i have a bad water pump (it would "pee" water when I had it up and going, but apparently it was not running all the time) and my engine overheated and damaged the top two cylinders. Turns out to my warning horn is defective so I didn't know it was going out because of overheating. So now he says the motor is shot. He showed me the damage to the two cylinders. It was running great when it was running. Should I have him slap in a new water pump and horn, cross my fingers and run it till it dies? Or do I buy a new motor? I can afford the new motor, but after spending $10000 on the boat last year, it was not something I wanted to do. The mechanic says the boat is in such great shape he'd get a new motor if it was his (he doesn't sell motors, just repairs them). I know he's worried about his rep, but if I take it easy on the motor, then replace it in the fall, would it make it the season?
Bad Cylinders on 2002 Merc 150
I made the mistake of spending good money on repair only to replace a year later. After a bunch of phone calls I ended up finding a nice used motor, from a dealer, with some warrantee on it. Saved a fair amount going that route versus new. I wanted to sell the boat in a few years and didn't want to take the hit on a new motor so it worked well in my case.
look at blackbirdmotors.com you might be able to get a whole powerhead with warranty for a good price, they just bolt right on
If it has two bad cylinders and you can afford a "new" motor now, I see zero reason to put any money into the bad motor with plans to replace it in a couple of months. Defies logic for me. If it was me, I'd replace it. I wouldn't be happy as I'm sure you are not, but I'd replace it.
If you can afford a new motor, no messing around trying to shove money into something to be back at square 1.