2 people or less boat runs great 2 or more boat does not get up to planing

[chbuerk]

I have a 16' starcraft I believe it is an a 1967 with a 1967 60 hp sportfour evinrude outboard. When I take the boat out with 2 people on board the boat reaches top speed and gets up to plane. When I have more than two people on board the boat does not reach planes and does not reach top speed. The motor does not miss. I do not have an rpm guage so I don't know what the rpms are. I moved people around to distribute the weight in the boat. I was wondering would this be a tilt problem? Or could there be another problem?

I am new to the boating world and would greatly apprcieated any help thank you.

 

[F_R]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

Sounds like a weight problem. Somebody might have to stay home.

OK, yes you can experiment with different tilt angles, spend money on props, etc. Might help, might not.

One last comment--it is possible the motor is not running on all four cylinders. Try a new set of spark plugs. If that doesn't help, it gets somewhat more complicated to check it out.

 

[QC]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

I was wondering would this be a tilt problem? Or could there be another problem?

Sounds like a power problem, as in you don't have enough. Every boat changes with additional weight. Smaller, lower powered boats, struggle the most. I am thinking this may be nothing more than that. Maybe some others can relate info from similarly powered boats. Do you have power trim and tilt? Or manual? If so, in either case trying different trim or tilt positions can help. You need to experiment

 

[Chris1956]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

Gee, I would think a 60HP motor would plane a 16' aluminum boat with 4 people, unless they were sumo wrestlers....I lean toward the run on 2 cylinders theory.

 

[QC]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

I don't know enough about Stratcrafts to comment, so I probably shouldn't have . . . :facepalm:

 

[BonairII]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

I lean toward the run on 2 cylinders theory.

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Or you are grossly overpropped.

 

[chbuerk]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

Thank you for everyone's responses. I just pulled the spark plugs two are carbon up and the other two seem to be still clean and not firing. I recently just put new plugs in. I looked at the distributor cap and seen that one point was not opening far enough I reset the point. However, my plugs have oil on them and around the oustide of the plugs. Does this mean I have a blown headcasket or could it be from the plugs not being fully in?

 

[Chris1956]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

The only way to know which are firing is to get her running in the water and pull a spark plug wire off and see if the motor changes speed.

 

[Rick.]

Re: 2 people or less boat runs great 2 or more boat does not get up to planing

Sounds like your on the road to recovery. Just thought I would try and dispel the idea that you don't have enough motor. I run a heavy 16 foot aluminum with a 40HP Johnson and it always gets up on plane no matter haw many people I pack in it. It takes a lot longer with more weight and the top speed always diminishes as weight goes up but I really think you have more than enough engine. Trim will make a huge difference when not set right. Best of luck with your spark problem. Rick.