1969 40hp Evinrude prop

[rustyzipper]

Greetings. I'm hoping somebody can help me with what propeller(s) should be on this outboard engine? The engine came with no manuals or a prop for that matter.

Engine model # 40953R.

 

[steelespike]

Re: 1969 40hp Evinrude prop

In 69 standard prop was 101/2 X 12 optional was 103/8 X 11 1/2, 10 3/8 X 13 1/4, and I believe 10 3/8 X 14.On aftermarket props diameter may vary.
The actual prop selection would depend on your particular application and activities.

 

[rustyzipper]

Re: 1969 40HP evinrude prop

Re: 1969 40HP evinrude prop

Thank you steelespike.

The boat, a 15' Glassmaster, runabout.
The previous owner mentioned the craft
had issues planing out, taking a long time to do so.

Being a first time owner I'm not really
sure of correct prop, applications.
I was looking at the Piranha composite props.

As far as activities, just fishing for the most part.

 

[jay_merrill]

Re: 1969 40hp Evinrude prop

If your boat is the 15' Glassmaster trihull, you should be able to run a 13" pitch prop on it. I had one, which at one point, had a single 1958 ERude 35hp Bigtwin on it. I ran it for awhile at a light load with a 14" pitch wheel, which was a bit overpropped. Since the wheels for the Bigtwin & Seahorse 35hp motors were the same as for the 40hp Lark and Super Seahorse models, the comparison should be valid.

I just looked at the prop sales section here at iboats and you can purchase an 11-1/2 inch pitch wheel and a 12" pitch wheel. The 12" version comes in Michigan Wheel and Quicksilver brands, for $87.99 and $114.99, respectively. I bought 14" wheel in the Michigan Wheel brand as recently as 5 years ago, but it looks like the selection for these old pin drive props is diminishing rapidly.

Bear in mind, also, that you can have an aluminum wheel re-pitched. I believe that they can be pitched-up as much as an inch to an inch & 1/2. You might also try surfing the auction sites for a 13", 13-1/2" or 14" pitch wheel, depending on which one seems to be right for the boat.

 

[steelespike]

Re: 1969 40hp Evinrude prop

What year is your glassmaster.It appears the 15 weighs in at about 900.
It would seem to me the 40 would have a tough time planing it quickly.
Brochure says standard is 10 3/8 X 12.I would think this would be for the typical boat the 40 would be on.I think a 900lb boat would be near the top for that prop Especially if you add a couple of buddies and some gear.
I would start with the 12 and adjust from there.If the 12 comes up light you can allways throttle back a little if you end up over propped you just plain shouldn't run the motor over anything more than 1,500 or so rpm.
You shouldn't run without a tach.A Tiny Tach is reasonable ,easy to install and fits any similar motor without regard to stator poles.