86 14ft bayliner 50hp

[jeep(0lll0)28don]

Hows it going. Have a 86 bayliner 14foot with a 50hp on it. Not sure what the best prop is for it is I have put a 11 1/2 on it and it wont go
And 12 1/2 it dose a litter better than the 11 but it just doesn't seem like its reaching its top rpm. I'm lost on this thing. I'm running 50-1
With two people I'm getting about 22 - 24 mphs most of the time 22 mphs
With three people 14. I was told that that the 11 1/2 would make the rpms higher and go faster but its slower
What am I doing wrong?

 

[jerryjerry05]

Re: 86 14ft bayliner 50hp

Motor operating at full?
Compression test.
Plugs burning right?
Then a tach will help.
A tiny tach can be bought and installed to give the right readings.
Without a tach were just guessing.
Need to figure out the rpm's at wot.J

Then put this in the prop section.

 

[Frank Acampora]

Re: 86 14ft bayliner 50hp

Without a tachometer you have no way of knowing what the engine is doing. The tach is the most important instrument on your boat. With it you can tell if you have the correct prop and once you have the correct prop, the tach will tell you if the engine develops problems.

That said, small boats are more sensitive to load than larger ones. However, on your hull with a well running engine and correct prop I would expect around 27-30 MPH top speed with you alone in the boat. with two other people I would expect 23-25 MPH.

SO: Yes, your speed is a little low and moreso under load. Check that the compression ratio is good and that you have adequate fuel delivery. Then, buy a tacometer and see what the wide open throttle readings are. Try to use a prop that will keep the engine within the top of the published operating range at wide open throttle. with that engine you have limited propeller choices so do the best you can.

also, set the tilt bar in the hole of the transom clamps that gives you the best speed. Usuallu it will be the hole that sets the cavitation plate parallel with the bottom of the hull. Be sure that the cav plate is even with the bottom of the vee or even slightly higher.