Thread: 95 15hp johnson no power

I Have a 95 15 hp with no power on top end will push my 12 foot alweld only 6.5 mph . I have changed coil, rebuilt carb, rebuilt fuel pump checked ing dva specks, compression 120 psi in both cyclinders good spark . This thing driving me nuts.

Have you done a link & sync? It must be done exactly in the steps given in your manual. Are you dropping a cylinder at higher RPMs?

You didn't mention sparkplugs. I had a 15 do that to me. I went through the whole engine, I tore it down in my frustrations. Even put brand new plugs just like the ones that were on it. Come to find out it was the wrong plugs for the engine. Just a thought, check the manual or parts dept for the correct plugs.

"gene"

Heres two other possibles , long shaft motor on a 15" transom will cause drag.

Also wrong prop or rather wrong prop pitch. I have a 25 HP 1992 Evinrude that I put on a 13-1/2 foot skiff. By myself it would only go 13-16mph. Cousin of mine suggested that the Evy may have come off a lighter aluminum boat. I had bought the motor at a garage sale. Since skiff was fiberglass he said different prop was needed due to greater weight.

Man was he right, it now threatens 30mph and thats all the faster I care to go in that particular boat.

Took off Flywheel found the dreaded brown goo under stator also plulled head gasket to look at cylinder walls head gssket was blown between cylinders thats why it had 120 psi of compression on both cyclinders .Why i got it apart goinin to clean exhaust covers to get rid of all carbon and check under power head gasket for clogged exhaust tube. Both cylinders are just like new can still see cross hatch in walls. Will have back togeather today cant wait! Thanks for replys

Motor pushing boat 24 mph and just jumps on plane :D

That's great, now fishing can begin. Glad to hear you got 'er going, and sounds like she goes good.

"gene"