70 hp Johnson has no power

NE Bowrunner

Recruit
Joined
Jul 24, 2002
Messages
3
stalls when shifted into gear but if you floor it sometimes it goes but not very fast...doesnt seem to run roughly ...pulled the spark plugs when i got home ...top plug was tan and dry...2 bottom plugs were wet...this boat is new to me and its my first boat...a 74'<br /> I've read alot about coil failures online does this sound like a coil failure or am i completely off track?<br /> the engine does start and will idle<br /> any help is apreciated :rolleyes:
 

orca

Chief Petty Officer
Joined
Jul 12, 2002
Messages
422
Re: 70 hp Johnson has no power

G'Day Rule No.1 when diognosing any loss of power. Check compressions. When you have done that get back and I'll give you rule No.2
 

NE Bowrunner

Recruit
Joined
Jul 24, 2002
Messages
3
Re: 70 hp Johnson has no power

compression was tested...all 3 cylinders ok<br />where do i go from here lol?
 

wilde1j

Vice Admiral
Joined
Apr 15, 2002
Messages
5,964
Re: 70 hp Johnson has no power

Compression OK is what? Values?<br /><br />Verify spark to each cylinder by pulling plug wires off one at a time while running at idle. No RPM change means likely that cylinder has no spark. Check that cylinder with a neon tester in line with the plug wiring. If all have spark, you then need to check fuel below.<br /><br />Next, you need to verify fuel to each cylinder. Take a spay bottle w/ premix and spray into each carb when running at max power. From what you described about the plugs, the top cylinder may not be getting fuel. If the spray routine results in an immediate power improvement, I would suggest rebuilding/clean that carb.
 
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