89 johnson 150 gt v6

fishgulper

Cadet
Joined
Jul 5, 2007
Messages
13
engine idles fine, but when u give it throttle it bogs down really bad like the choke is sticking. it also wants to stall when put in gear. could it be water in fuel. I put new fuel/water seperater on and pulled the carbs off and cleaned them. the boat sat in a garage all winter with approx. 5% fuel. I was driving down lake with what fuel i could get, felt like only one carb was functioning, and kind of felt a bump of power. i then opened throttle up and took off the way it should, but when i brought back down, same thing happened again bogging down like its not gettin fuel.




any response greatly appreciated
 

Brew2

Chief Petty Officer
Joined
Jan 12, 2004
Messages
427
Re: 89 johnson 150 gt v6

G'day to a fellow Albertan!

Chased a similar problem in my V4 for a long time. These loopers really like their gas, so any sort of blockage/slow down in fuel delivery makes the acceleration bog happen.

Could be any number of things from an air leak somewhere in the fuel system (check all the connections and replace old brittle hoses), varnished carbs (should be ok if you cleaned the carbs/jets....did you replace the carb gaskets to ensure there isn't an air leak?), small kink in a fuel hose restricting fuel to one or more of carbs (look espicially hard at the one that feeds the bottom port cylinder, that often loops underneath the carb body and is hard to see), clogged inline fuel filter.

Re the 5% gas over the winter....don't do that. Completely fill the tank and include some sort of fuel stabilizer....the full tank willl eliminate the possiblity of condensation getting in your fuel system. Run the engine for a bit after putting in the stabilizier so the gas that gets left in the carb bowl is treated and doesn't varnish over the winter.

Good luck!
 

fishgulper

Cadet
Joined
Jul 5, 2007
Messages
13
Re: 89 johnson 150 gt v6

thanks for the info, i think the gaskets are good as i just rebuilt motor last year
 

Brew2

Chief Petty Officer
Joined
Jan 12, 2004
Messages
427
Re: 89 johnson 150 gt v6

Could also be the fuel pump heading south. If it is the original fuel pump (ie 20 years old), probably worth doing even if that isn't the ultimate problem. I think fuel pumps of that vintage still had a brown elbow where the fuel line connects....I think it changed to grey on newer models.

Lot easier to change out that fuel pump in your driveway than paddle back to the ramp from who knows where! If you are still using the VRO/OMS oiling system, then the pumps are unfortunately quite expensive, but can be found on ebay at a reduced price.
 

Brew2

Chief Petty Officer
Joined
Jan 12, 2004
Messages
427
Re: 89 johnson 150 gt v6

The other thing you can do to try and confirm it is a fuel delivery problem is to bump the primer (ie. push in key) a couple times immediately prior to accelerating. If this gets you "past the bog" then you know somewhere something is starved for fuel.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: 89 johnson 150 gt v6

do a link n sinc.

Ethanol and fuel lines
replace all fuel line with Alcohol resistant lines. Ethanol deteriorates, the rubber lines, then they start to sluff off on the inside, going directly to the carbs. Settling to the bottom of the bowl. Contaminating the carbs high speed jets. clean a rebuild carbs, flushing fuel line before connecting to carbs.
 

jriegle04

Petty Officer 2nd Class
Joined
Jun 1, 2009
Messages
179
Re: 89 johnson 150 gt v6

i would check my spark if i were you. i just went through a similar issue with the 1985 150GT and found i had intermittent spark on the 3 cylinders on the side of the starter. it idled fine but when put into gear it would die. i found a loose magnet under the flywheel. with a small investment of JB weld it should be fine for very little cost. just a thought.
 
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