1988 Johnson GT150 acceleration issues

[wmgeorge131]

Engine will start an idle fine except when I press hotfoot to accelerate the boat will only go anywhere between 11 and 29 Miles all spark plugs , wires, and coilpacks were changed Carburetors cleaned but jets were not touched Any suggestions?

 

[racerone]

Post the compression test values.----Are the fuel jets ( FIXED ) clean ?----Does spark jump a gap of at least 3/8" on all leads ?-----Flywheel key checked ?----Any history on this motor ?

 

[Chris1956]

Does the linkage to the carbs and trigger move to WOT?

If you pump the primer bulb, does she then accelerate?

 

[wmgeorge131]

Linkage to carbs moves ok i havent tried primer bulb this is normally a 50+ mph boat.

 

[wmgeorge131]

Post the compression test values.----Are the fuel jets ( FIXED ) clean ?----Does spark jump a gap of at least 3/8" on all leads ?-----Flywheel key checked ?----Any history on this motor ?

I dont have compression test, jet weren't touched and spark dose jump at least 3/8" this is normal a 50+ mph boat only started having this issue after boat sat for about 3months with no use.

 

[wmgeorge131]

Engine will start an idle fine except when I press hotfoot to accelerate the boat will only go anywhere between 11 and 29 Miles all spark plugs , wires, and coilpacks were changed Carburetors cleaned but jets were not touched Any suggestions?

This is normally a 50+ mph boat only started having issues when boat sat for 3 months with no use. Location Alabama

 

[Crosbyman]

do google or utube searches on bogging outboards .

Fuel starvation seems a frequent cause assoc. with air leaks, degrading "grey" fuel lines, dirty filters etc...

 

[wmgeorge131]

Thanks will do

 

[Crosbyman]

see #15's easy access probably ...run a carb cleaning tool in the jet followed with a shot of carb cleaner. a 2lb mono may do the job

 

[racerone]

Do not run motor till issues are sorted.----A cylinder starving of fuel starves a cylinder of OIL as well.

 

[ct1762@gmail.com]

id remove the heads to inspect cylinders now on description of lenght of time this motor was run in this horrible lean condition. as soon as i sense something isnt right with any motor, i immediately head back to the dock and keep tapping the primer.