i have an 18 feet bowrider with the 4.3 mercruiser ...i replace the 3 blades 14 1/4x 21 for a 4blades 14x19 can anybody tell me what could happen please...im not an expert
Great video Bill! You know a lot about boating! I check my numbers every outing bc my boat only has one speed... full throttle!! And I still get passed by the bass boats like I’m not even moving 😂
Hey Bill I'll enjoy watching you and Mike D ya yeah you just taught me a little bit about props I sure do thank you brother you and your family have a happy New Year and have a blessed day and God bless you all
Thanks for Video dude. When I prop out a boat I actually do the opposite of what you do. I'll take it out with maybe 1/4 tank of fuel in the boat and just me and no gear (the lightest load possible). Then I go wide open and look for the manufacturers maximum RPM w/o hitting the rev limiter. I just got a new Trophy T22 with a Merc 150 and it came from the factory a little over propped with a 17 pitch running at just 5250 to 5300 with just me and 1/4 tank (15 to 20 gal). I dropped the pitch down to 15P and got 5700 rpm which is just shy of the max RPM of 5800 rpm for the engine. Got a lot better dig outta the hole too.
I have a heavy boat its a 2320 parker marine with single 250 Yamaha on the swim step with fully enclosed transom. at full load 8500 lbs with 17 pitch im at 4600 rpm and can't even get on plane I was looking at the Yamaha saltwater series 15 3/4 pitch 15 what do you think as I've tried an aluminum 15x15 and it still won't plane help? im outta ideas
What diameter is your current prop? And what model prop? I can tell you from experience that Mercury props are top of the line and using flo torq hub kits they fit any engine. I’d try a Revolution 4 blade 15 pitch
Got a 1978 2storke 15h on a 14ft aluminum V haul Jon boat. With two people I was running about 5700 RPMs the motor calls from 5500 to 6500. The prop I got is a 9 1/4 x 10” pitch I’m wanting to get a little more TopSpeed would you suggest going up a pitch or not
Sounds like its about right. Fully loaded you want to be around the 5500 and 200 rpm really will not increase speed too much honestly. Hope that helps.
The dealer lost my prop in prep and put a dang 14inch 13pitch on it and I can’t even go past half throttle and was turning 6000 rpm waiting on the closest to a 14inch 17 pitch prop to test out 13.25x17 if it still hole shots great I’m gonna try a ss 4 blade 14 inch 19 or 21 pitch. 2021 90hp four-stroke merc 2.07 or 2.08 can’t remember the exact gear ratio gearing on a 17’9 crest liner xf
I went from an aluminum Black Max 13.5 X 23p to a Laser II 13.5 X 24p SS prop and lost about 1000 rpm and 3 mph from the aluminum. Any thoughts? It was what the shop had on hand. Probably should have gone with 21.
Yes although I think 1000 RPM it might be that your old prop was missed labeled or reworked. There is some differences between aluminum and stainless as the stainless does not flex as much as the aluminum but when you went up one pitch that Alone will lower the RPM 200 by itself. You also got to put into account that they are two different style props as far as rake and cup. So lots of variables it’s all trial and error pretty much. Hope that helps
Mercurys owners manual , states this - to extend the longevity of the motor to run it and or around the power range.. mine is 6200 rpm.. run those motors folks !!
Bill I have a problem, how are first of all! Pray all is well. I changed the lower unit on my mercury 200hp black max. I put the same prop on the lower unit and now it won’t run past 5,000 rpm at 41 mph. On my old lower unit it ran 45 mph on 5800 to 6000 rpm. What went wrong? Vengeance 14.5 17p. Help me out please. Appreciate you
No, the diameter is not the circumference, the diameter is a straight line measurement tip to tip of the blades, and as you said, the circumference is the distance all the way around, two completely different measurements.
Yeah this was one of the videos I think I need to update. There is so much that I could have done better. I think I am going to do another one explaining it in detail. Thanks for watching
The diameter varies among the different model props. The pitch is manly what you adjust for performance. But diameter can also give you better performance especially on bigger engines 300hp and above
I'm going to try going all the way down to a 10 pitch, but I spend 90% of my time trolling. The goal of going down that low of a pitch is to get a trolling speed under 2 mph. I got a F115 Yamaha on a 20ft Skeeter tiller. With my 17 pitch prop I got about 2.5 at idle. Hopefully the lower pitch will get me there otherwise I'm going to go back to the stock pitch.
@@catchonedrinktwo yes 💯. But that would negatively effect the top end too. A 10 pitch prop is supped to turn 10 inches every revolution in theory at least.
Last time was the wahoo video a few weeks ago. The weather has been too rough when I have the time off. I’m ready though as soon as I see a window. Thanks for watching
Thanks for information. I’ll be propping my boat out soon. It’s getting gel coated and a bigger tunnel added. It’s a 2008 Ultra Cat 20 foot with an 2008 Evinrude 150 hp motor. I run in the shallow water, 2-3 foot drifting when fishing the Lower Laguna Madre by South Padre Island, Texas. I had been running a 19 inch pitch. With a larger opening in the tunnel I’ll have to check what the RPMs will do. Thanks for the education. What motor are you running and what pitch and how long is your boat? I’m familiar with the Shoalwater. My boat has a full tunnel as well.
With the dirty water, I have to run a lot of cup in my prop and it works really well. There are a couple guys in Texas who specialize in tuning the props for our style boats. I run a Mercury Revolution 4 blade prop. It is a 15 pitch, with a triple cup added. And I turn right at 5800 rpm. So i basically bought a new prop and had to send it off to have it cupped. lol but she runs really well even in corners.
That is 13min of my life all never get back Like that say a little knowledge is dangerous, go find out about prop dim then remake your vid I’ll give ya a little hint one inch of dim is worth 2in of pitch
@@JackedUpFishing bro you never spoke about diameter one inch of diameter is worth 2 inches of pitch so that is 400rpm per each inch of diameter, like I said go read up on propeller dynamics then come back and redo this video and people will think you really know about props, also you can talk about cupping, that is what keeps your prop in clean water, and also learn about the rake of a prop
@@reelnative01 yeah I am sure there are more experienced people than me in the prop world but I have over 100 props in my shop and prop boats a lot. So I must be doing something correct. Thanks for watching though... not gonna argue about it all as there are lots of variables. Go up 2 pitches and your Rpm will drop 400 on the gauge. Simple