1962 evinrude fastwin on a 1236 aluminum john boat motor height.

[Chrisham]

The cavitation plate sets 2 inches below the boat bottom
It seems to take to long to plane out .It has a 2 blade brass prop.Does the motor need raising

 

[Chrisham]

Correction the motor is a 1962 model

 

[jbcurt00]

Correction the motor is a 1962 model

Corrected title to 1962

Yes motor needs to be raised

 

[racerone]

The 18 HP motor should make a 12' boat fly at 25 MPH.-----Are you sure motor is in good condition ? ----Properly adjusted carburetor ?----Running on both cylinders?

 

[Chrisham]

2 inches?

The 18 HP motor should make a 12' boat fly at 25 MPH.-----Are you sure motor is in good condition ? ----Properly adjusted carburetor ?----Running on both cylinders?

Yes sir runs fantastic .cranks first pull and idles fantastic.Just got her running with your help.It will get fast but takes a while to get there.I was wondering if the low cav plate is plowing making it hard to get planed out

 

[racerone]

Maybe try a regular 3 blade prop with 10" pitch.---What pitch is the 2 blade prop?

 

[Crosbyman]

Q:? was is the boat rated for...18hp on a 12 footer sounds likea flipper to come

 

[airshot]

Raise motor until cav plate is same height as boat hull....is cav plate level to boat hull, use long straight edge to check. How is motor trimmed ?
What is compression on both cylinders ? Why a two blade prop ? You need a tach to get real readings in motor performance.

 

[racerone]

Barn find motor likely came with the 2 blade ?-----Popular option in the 1960's I think.

 

[Chrisham]

Q:? was is the boat rated for...18hp on a 12 footer sounds likea flipper to come

Rated for 15 hp .I have run a 1972 25 hp on it a lot and it will move

 

[Chrisham]

Barn find motor likely came with the 2 blade ?-----Popular option in the 1960's I think.

Estate sale and yes the prop was on it

 

[Chrisham]

Raise motor until cav plate is same height as boat hull....is cav plate level to boat hull, use long straight edge to check. How is motor trimmed ?
What is compression on both cylinders ? Why a two blade prop ? You need a tach to get real readings in motor performance.

The cav plate is 2 1/4 inches below the hull.Compression 112 both cylinders cold.Motor was trimmed all the way down

 

[Chrisham]

The prop came on the motor.I bought it at an estate sale out of a barn
SHE IS A GEM EVEN LOOKS GOOD

 

[Chrisham]

Maybe try a regular 3 blade prop with 10" pitch.---What pitch is the 2 blade prop?

I have no idea.Its a cool looking prop

 

[racerone]

If your " cool looking " prop has too much pitch , then acceleration will be slow.-----Have you adjusted carburetor mixture screws for proper performance , yes , no or no idea how?