View Full Version : Another Prop Question
I just took my new to me boat out yesterday and had a question about the prop pitch. It's a 16.3' Searunner with a 2000 Honda 50hp four stroke.
Spec's say 5500-6000 rpm WOT. I ran about 3000 rpm wide open. It was doing 27mph according to gps with two in the boat. The motor seemed to run fine and tach showed about 800-950 rpm at idle so I don't think tach is wrong. Prop is stamped 11.1 x 13 - 3 blade. I am courious as too why so low of rpm. :shrug: Any input would be helpful.
5150Dan
11-17-2008, 08:23 PM
If you are not getting enough rpm's you'll need to get a different prop.It is an easy fix but the best method is to ask the boat where you purchased it,let them know you are not able to reach max. rpm. They should be able to steer you in the right direction.
Dan
Starfish
11-17-2008, 10:07 PM
Sounds to me like your tach isn't reading right... you said it "seemed to run fine." If you were really lugging it at 3000 RPM at WOT it should have sounded a bit labored and I would think you would be struggling to get on plane. A 13" pitch prop ought to be able to spin up pretty well with a 50hp, and the fact that you got 27 mph indicates you were turning the prop fairly well. I don't have any experience with that particular boat/motor combo but I know when I briefly ran an 18' boat with a 55hp outboard I was still able to turn a 17" prop with it. I can't imagine having to drop lower than 13" with your rig. See if you can get your tach checked out before changing anything.
I called the dealer and he told me about the "pulse" setting on the back of the tach. It is probably on the wrong setting. The previous owner put the motor on the new boat. He didn't recall what rpm it ran. It's probably been wrong since day one. Thanks for the input!
The setting on the back of my tach was set wrong when I picked my 20ft Seahawk last year. 150HP Honda and was only getting 4000 rpm, after they adjusted the tach it now goes to 5500.
Didn't go any faster though! :laugh: