1989 Force 125hp-how fast are they?

[Champ9969]

I have '89 125hp on a 18 foot bass boat.With different props ,I can only get 36-37 out of this motor.Is this right? or can I do something else like increasing the pitch into the 20's?

 

[JB]

Re: 1989 Force 125hp-how fast are they?

Hi, Champ.<br /><br />You need a tachometer to tell if you have the correct prop.<br /><br />The correct prop will top out at about 5500rpm.<br /><br />What are you measuring speed with, water speedo or GPS?<br /><br />Good luck.

 

[Champ9969]

Re: 1989 Force 125hp-how fast are they?

J B...I run 4400 with a 19p 3 blade & 5500 with <br />a 4 blade 15p and yet the speed(by GPS)stays about<br />the same.My next move is a 3 blade 17. The book says 15-17-19. Do you think I can go 23pitch even if my r's are low?

 

[FlyBoyMark]

Re: 1989 Force 125hp-how fast are they?

Nope...RPM's will be even less and the boat will slow down more.....Your speed is a little on the low side....I would tend to tune the engine up and check the compression and see how low it has dropped from spec or if there is any major difference between the cylinders. You might want to to take a look at excess weight in the boat or if it might have water hiding somewhere....

 

[sony2001]

Re: 1989 Force 125hp-how fast are they?

As I found out the 13X17 three bladed is the best all around prop. I lost 1 mph compared to the 19 but everything else was better.

 

[Champ9969]

Re: 1989 Force 125hp-how fast are they?

Thank You all!!! Going to get this right because of your valuable input!