Help with prop ? for Force please

[wj3v]

I need a little help from the experts out there. I had a little accident and ended up with a bent prop. I have a 1991 18 foot maxum bowrider with a 90 hp force. I need to purchase a new prop and have no idea what to get. The only number I can find stamped on the prop is 15. My current top speed is around 32 mph and at a little less than 5000 rpm. After my little mishap I took a pair of pliars and straightened the one bent blade and it seemed to be OK. Will it hurt to contine to use it? Thanks for all replies!!

 

[alounsbury]

Re: Help with prop ? for Force please

The number 15 is the pitch of the prop you are currently using which represents the distance the propellor would travel through water with no friction. That is 1 full turn of the prop should propell the boat 15". The diameter should be 13.75". I have a 93 Force with a 15" pitch as well. It is a good idea to always have 2 props with you, just in case you have an accident with one. Depending on how badly you bent the blade, the prop will now be out of balance. The degree of how out-of-balance it is will dictate the amount of damage it can cause to the lower unit. I would recommend taking the prop into a local dealer and have them rebuild/repair the damage prop. Optionally you can purchase another one as well.<br /><br />As you are running close to 5000 RPM (recommended for force), I would not change the pitch of the prop or the replacement prop.<br /><br />A good place for more information on propellors is at http://www.boat-propellers.net/

 

[StringBox]

Re: Help with prop ? for Force please

I'm still working out the bugs on my last boat project, but also had to replace a prop and ended up with the same problem. I ended up going with a Hustler aluminium prop from Boaters World. It's a two piece unit with a center hub and prop housing. The Hub was about $50.00 bucks and the prop housing was $59.00. Cheap as it gets to replace a prop.<br /><br />Sounds like you have a 15 pitch prop, but I'm guesing. You might take your prop and compare it to those at the store to find a match. <br /><br />I beleive you can also measure the length of the blade from the front to the rear, multiply by the number of blades. That should be your pitch.<br /><br />decreasing the pitch by 2 inches should increase your engine rpm by about 400 RPM's.