Recently bought a '98 Triton bass boat for cheap as a project boat.

First project setback was the engine failed its compression test. Johnson 150 had four good cylinders and two showing low compression. Motor will run, but will never run well without a major rebuild.

Any advice on motor rebuilds? (Please phrase at beginner level, since I know little on that topic.)

My (good) small repairs guy thought it would be about $3,500 for a rebuild on that motor. (Which he does not perform.) Is that a worthwhile expense on a '98 Johnson motor, or is that getting too old to put good money back into it?

I also have a Mercury 150 on the boat I inherited from my father. That is about an '84. It has very low hours for such an old motor, because he usually fished on a "no gas motors" lake. I am going to take that motor in for a compression test next.

If both motors are in similar shape and need an expensive rebuild, is there a strong preference for one make? For example, is one brand more likely to still have parts available for older motors in 10 more years, does one brand have much longer run times between major repairs, etc.

Thanks for any wise advice that may help me get back out to fishing!