Cannot find numbers on Prop.

[plsports]

I bought 1 1988 15' Bayliner Trophy Bass last week with a 50 hp Force. i will be getting a tach on the engine this week whenever teh sun decides to roll in. Anyways i have 2 6 gal fuel tanks in the rear along with my life jackets, all under the rear casting deck. in the middle between the seats i have one battery and right below the beginning of the front casting deck i have the 2nd battery. I have a 40lb minn kota on the bow. The boat is running about 23mph with me in it and is not breaking plane. i have tilt and trim but anyway i have ever ran our ski boat is leaving the trim down until breaking plane. if i throw a 2nd passenger in i drop below 20 probably closer to 15. i pulled the prop and the only thing i could see stamped on it was 11 1/2 along with the pros serial number which was 48819336A40. the engine seems to be running fine but like i said i will be getting a tach on her this week. any help here would be great thanks!

 

[steelespike]

Re: Cannot find numbers on Prop.

I'll assume the motor is also an 88.
It is most likely a 11 1/2" pitch.that is on the low end of selections
It is unlikely the boat is doing 23 and not planing.the speedo may not be accurate.
I have a feeling your actual top speed should be between 25 and 30.
If the motor is struggling check that it is running on both cylinders.You wouldn't be the first to not realize that.Be sure the throttle plates in the carb are opening all the way,see if it responds from a tickle on the choke,the prop is in excellent shape,bottom clean and smooth.
We can tell better where your at when you get the tach going and maybe borrow a gps for the speed.