power of a 20 hp johnson

[used motor]

hello,<br />would a 83' 20hp johnson push a 14' starcraft 69'<br />or need a larger engine?<br />just using for backwaters ,backbay cruzing.<br />thanks

 

[used motor]

Re: power of a 20 hp johnson

thanks for the fast reply.<br />not alum. bow closed 2 seater fiberglass.

 

[alden135]

Re: power of a 20 hp johnson

I had an old mfg fiberglass 14' boat w/a 18hp e-rude. The boat would plane but not with more than 2 people and little gear.

 

[CATransplant]

Re: power of a 20 hp johnson

Sure it will. If this is the typical open alumimum Starcraft, a 20hp outboard will plane it right out with good speed.<br /><br />It'll also slow down enough to allow trolling in that boat.<br /><br />This is a lightweight aluminum boat, right?

 

[papa_Lazerous]

Re: power of a 20 hp johnson

it'll push it along fine, I have an old 20HP '73 fastwin and that pushes my 16ft Norman along quite well. your boat is smaller and lighter and a newer engine

 

[used motor]

Re: power of a 20 hp johnson

thanks for the advise CATransplant,<br />one more thing sorry changing subject--<br />runs strong-yes but can only keep her at strong idle.<br />I cleaned carb over 3 times cleaner& air press<br />just want a smooth low idle.<br />I've heard older motors are hard to keep low idle<br />Im pretty good with 2-stroke outboards.<br />was a parasail mate for 3 years.<br />Went thru 2 yamahas 50 my boss ruined (good Boss)<br />just did'nt care for the shuttle. (his party taxi)<br />shame <br />any ideas? could it be a bad choke spring?<br />thanxs 1st mate/mech/mate/mech ect....<br />thanks have a good one...

 

[CATransplant]

Re: power of a 20 hp johnson

That could be another matter. It'll push that boat, but may have trouble keeping it on plane. It all depends on how the motor's running and how heavy the boat is.<br /><br />I think you might want a few more horsepower for that boat, but I can't say for sure.

 

[CATransplant]

Re: power of a 20 hp johnson

One more thought: If you're truly just going to use the boat for poking around and aren't planning to do a lot else, then the 20 hp might just do for you.<br /><br />If it's in good shape, and it proves not to be big enough, it should be easy enough to sell for what you gave for it. Lord knows that there aren't enough good-running used motors, and some guy with an aluminum boat would probably snatch it right up.

 

[CATransplant]

Re: power of a 20 hp johnson

I don't know that model well enough to advise you on the idling problem.

 

[papa_Lazerous]

Re: power of a 20 hp johnson

twin cylinder 2-strokes dont idle too well in general, you need a strong spark good compression good reeds (if your model has them) there may be a knob to adjust fuel mixture at idle on the front of your engine. if you emgine pops and bangs at low revs like its running out of fuel rich it up half a turn.<br /><br />My needle was way out on my 20HP fastwin I wound it in till it stalled and then wound it out till I got a good idle.<br /><br />Another thing is use a good 2-stroke oil that has an affect on good tickover