Who Knows About Props?

[vernonfarmer]

This very heavy, bronze, two blade prop was on the 1959 60 hp McCulloch Flying Scott when I got it last year. Just now cleaned it up and can see a few numbers and the word, "Michigan" stamped into it. Numbers found are, AJC120 and 953M. I'd like to learn whatever I can about it. Thanks.

John

[a j r]

Michigan Wheel was a major maker or propellers. Maybe they still make 'em. I don't know what the numbers mean. Usual diameter and pitch.

Andreas

[Ron P]

I'm quoting from a OMC Prop catalog.

Two Bladed propellers are generally used for high speed running with very light loads- as in racing. A four bladed propellar is used on large ,slow moving boats, where great thrust, but little speed, is needed.


Also a note about pitch. If the boat has a 20" pitch. This means the distance the prop will theoretically travel in one full turn.
Pitch is the twist or angle at which the propeller is set to the direction of travel.

Propeller Diameter is the diameter of the circle desribed by the tips of a rotating prop.

A prop used for sking would be a lower pitch. You need greater acceleration and thrust to get the skier on top and boat on plane.

Using a lower pitch ski prop for cruising has some risk of overspeeding the motor. So if a higher pitch cruising prop is used for sking it will tend to overload the motor.


Now after reading the above you are still confused. think about these prop changes as it pertans to a smaller outboard tring to do all things well. Say a 40 hp . The prop will have a noticable affect... If you are running a larger motor 75hp on up not so much.

I hope this helps.

[Phill Blank]

John,

Here is what I found out about the bronze prop you had questions about.
I sent an email to Michigan Wheel the manufacture of the prop you have. They are still in business and have a nice web site at www.michiganwheel.com here is the answer they sent to me.

"Thanks for your inquiry about the subject propeller. After a bit of research I found out it's a 11 1/2" diameter by 15" pitch, Bronze 2-blade propeller used on the following motors (apparently in addition to the 1959 McCulloch 60 HP Flying Scott motor).

60 HP Wizard made in 1960
60 HP Scott-Atwater made from 1958-1960
60 HP Elgin made in 1959 & 1960
50 HP Homelite (same as McCulloch?) made in 1961

Hope this helps and thanks again for your inquiry.

Sincerely,
MWC Customer Service - Outboard Division"

I always say go directly to the source and get the answers.

Hope this helps you.

Phill

[vernonfarmer]

Thanks, Phill...you da man!

john