Logo

What prop is it

junky

New member
"The only markings on it are M

"The only markings on it are MICHIGAN 01203.Any one knows,please help.Looking to get more speed out of my boat.The prop is on 1980 60 hp small gearcase evinrude,boat is 1969 winner 16 ft.Top speed is about 26 mph on the gps.The old motor which was 1969 55 hp evinrude was faster.No tach on the boat.Any help realy welcome.Thanks Kris"
 
"Kris, you don't have enou

"Kris, you don't have enough numbers there -

Michigan 012036 would be an 11 pitch
012037 - 13 pitch
012038 - 15 pitch and
012039 - 17 pitch

Additionally, without a tach there is no way to "guess" at what may be the correct pitch prop for your rig. Simply adding more pitch could result in severe damage to your motor.

If it's already into its optimum rpm range with say a 13 pitch, moving to a 19 will not only NOT give you more speed, it will labour the motor severely possibly causing detonation and piston damage.

More Pitch = More Speed ONLY if you have the motor underpropped to start with.

In general, unless you are running very light with an aluminum hull, I would expect a 60 to be spinning nothing more than a 15 pitch prop when hangin' off the back of a 16' boat..."
 
"Thanks.I rechecked the prop a

"Thanks.I rechecked the prop and there are no more numbers there.I will try to check the rpm with timing light, on the wather with reg load at wot..With the info on rpms and speed it might be possible to guesstimate the pitch .If I can't get more speed out of this one I guess the next option is ti repower with 75 hp.The boat is rated up to 85 so 90 might be too much.Thanks again,I'll try to check rpms over the weekend."
 
"I had the prop checked by a g

"I had the prop checked by a good prop shop and they say it is 17 pitch.So the problem could be too much pitch,I guess.Will try to check rpms soon.Thanks"
 
Back
Top