1999 Crestliner Sportfish 1750 2001 Merc 115

I have been running this boat for about 5-6 years. I just wanted to see what props you guys and gals are using. I currently have a Revolution Not sure what it is called SS 4 blade 19*. The issue I have is when I am fishing with two others (3 total), it seems like it does not have the POW to get up and go. Now I am guess that I need to work the trim better etc. etc. etc. Just seeing what everyone is running. Merc is a strait carb no efi or any of that fun stuff. Needing to get a new prop as a backup anyways.

Thanks
HTTU

Sounds like you have too high of a pitch. I would start with putting a tach on if you don’t already have one. Your outboard probably has a max RPM of around 5000-6000rpm, look at the spec to see what it is. Now, measure your rpm at WOT with both minimum load and maximum load. Usually, going down in pitch by 1″ will raise your RPM by 200, as long as you are using the same kind of prop (In your case a 4 blade stainless).

One other thing you can do to get more RPM is to raise your outboard with a jack plate. The higher the prop is in the water, the less drag there is. This adjustment can make a huge difference.

Without knowing your RPMs, I’d also guess you have too much pitch. If your going to buy another 4 blade, your probably looking to drop 2 pitch sizes, and probably 1 if you go with a 3 blade.

this is what I learned from the guy I work for at a boat/motor repair shop who has mercury factory training,regardless if the boat has an outboard or an inboard motor,if your motor is trimmed right on its lowest pin setting,when you go to full throttle,your engine should hit 3500 rpms without hesitation.
the engines rpm’s will climb as you trim out to get on plane,when you are at the motors optimum operating range, generally 5200-5500 on a merc,others will vary,you should be able to maintain speed and plane with out porpoising.

you will have to check this with a light load,and a full load,and as mentioned,you may or may not need a jack plate,but you may need a couple of props depending on what you find out that suits your needs,and you may find that a three blade prop will run circles around a four blade and vice/versa.

I have learned the last several years working on boats,even identical boat/motor combinations,no two will ever perform the same and you will need to tailor the prop to your liking, hope this helps and good luck!!!