Johnson 140 prop identification help

[jay2670]

Hello I re-powered my 1997 20' Trophy walk around with a 1983 Johnson 140hp. I was hoping the prop that came on it would be good for my needs but I am unable to get the RPMs and struggle to get it on plane. After a period of time it does manage to get on plane but top speed is only around 24 mph @ 2600 rpm and this is wide open. I am assuming I need to reduce pitch on prop. My problem is I don't understand the markings on the prop. Can anyone help?????

 

[jimmbo]

Re: Johnson 140 prop identification help

It isn't an OMC prop. The numbers on it don't match anything in my Michigan catalog. the 'M23' might idicate it is a 23 inch pitch. If so, way too big for that boat. I would ballpark a 13in or 15in for your app.