1978 Mercury outboard 80 hp, 4cyl. Motor starts but no power when throttled up-- also makes a knocking sound. Any suggestions on what to do? Rebuild or buy new? Dry docked in Connecticut.
nocking sound not good. wether to rebuild or buy new.. that is up to you..... if you rebuild it , it will be heeps cheaper than a new one, but it will perform just as nice... i say rebuild.. but thats just me
Have you checked the compression? Knocking sound definately is bad, but you might want to try decarbing with some seafoam. My inline 6 would idle fine on the muffs, but didn't have any power on the water. A couple cans of seafoam later I was screaming along at 50mph...
