I have recently purchased a bluefin aluminum boat, 1988 with a 1988 force outboard. I have been around boats all of my life and am very mechanically able to work on the motor however I'm not sure that it needs it. Here is my question, The motor only pushes the boat at 24 MPH top end and does not seem to be rapping out. I know the range of RPM that this motor is supposed to run, and am planning on purchasing a tach. I cannot find any markings on the prop which would indicate the pitch, that is my next step. I don't know if I should proceed in checking these things out, but I feel that the motor should be able to create more speed. Should I dig??? Or should I just upgrade in power???
Nothing at all stamped anywhere on the prop?Sometimes it just 2 #'s on the prop by the blades.If not then you need a prop shop to figure it out.Did you take it off and look?
How's the compression?
You really need a tach and somekind of # off the prop to figure out what you need.
That motor will run a long time.If you wan't more power and speed upgrade to a bigger motor.J
I am going to dig a little deeper into the prop. I have had it off and cannot find anything. I also know a used boat dealer in town here who may be willing to let me take three props with different pitches and try them out with the understanding that I might buy one. I have looked on another thread and seen that I can buy a tach to connect to the plug wire and get an idea of how many RPM's I'm turning, I am also going to check for spark and compression this weekend as I have noticed that seems to be common problems, hopefully it is not the compression. Thanks so much I'll keep you updated with what I do this weekend.
17 foot blue fin aluminum. Like I say that might be all I can get out of that motor, but am hoping to teach my 6 year old to ski. It should have enough power to do that.
I just bought a 14ft Bayliner Capri with the same motor. Just like you I was a bit surprised that the motor lacked so much power. I am starting to think tha these 50s are just not torquey motors.
I have a 1989 50Hp. My prop pitch is 10p. On a 16' fiberglass boat with two people I get 23 mph. So your motor sounds like its performing as it should. The max RPM for the 50Hp is 5500 RPM. To be honest with you, 50 horse is underpowered for a 17' boat. Even with diff pitch props I dont think you will get much if any more speed.