1985 Johnson 30 HP - No go on full throttle

[thoren1912]

I have a 1985 Johnson 30 hp motor that starts great and idles well. When I get up to about 2/3 full throttle (planed out and cruising) it starts to lurch. It usually doesn't do it right away but if I get up to full throttle and wait a couple seconds it starts to lurch. I am guessing that it has to do with fuel, either too much or too little. Any ideas or anyone else had this problem?

Thanks!

[marine_man]

Sounds like it could be a Carb related issue.. did you run fuel stabilizer through the motor prior to putting it away for the winter?

What happens if you pull the choke when it wants to lurch? Does it improve?

marine_man

[thoren1912]

I actually bought it this spring so i am not sure if fuel stabilizer was put in last fall but it is fresh gas this spring. Maybe I will run some carb cleaner through with the gas and try pulling the choke out when it lurches. I will report back what i find out. Thanks!

[marine_man]

I'd give that a try.. perhaps mix some sea foam in with your gas... it probably won't do the trick, but worth trying!

marine_man

[BoxMN]

Another thing I learned sort of the hard way, hehe, was that if the float is not set right it can starve for gas when you are giving her WOT. Mine happened right away, though, as I had float in upside down.... heh, dumb me... but if it is set too low, meaning it blocks off the jet not allowing enough gas in.

good luck, BTW, mine was basically same motor, a 25hp rude.

[chad austin]

Try squeezing the primer ball when it starts to "lurch". If this stops the lurching and your motor runs better, it may be sucking air somewhere in the fuel system. I had this happen to me a while back and it was the fuel filter that screws to the side of the block on my 15 hp johnson

[boatfixer]

Sounds like its starving for fuel. Dirty fuel filter will cause that to