Far2hip
Seaman
- Joined
- Aug 8, 2015
- Messages
- 57
I wanna ask a few questions on props and pitch, but first an explanation of that ridicules avatar I have above my name, lol. The iPad won't let me drag that little white box to choose that part of the picture to show so I have to get to my laptop to fix it later. So for the time being, yes, you are corresponding with a piece of vinyl siding, LMAO!!! Just don't let anyone see your screen and they won't call in for the white jacket just yet. Yet again, you do restore old boats so maybe you're already at that point of legally insane!! This is my first and I am already getting there!!
Back to the topic at hand, props.
I am sure that this topic has been beaten to death many times but I just need to hear it as directed at my specific situation. The boat is a 1964 14' Arkansas Traveler (very cool little old boat) fitted with a 45hp Mercury Classic 50 2 stroke 4cylinder outboard that revs at an optimal WOT range of between 5000 and 5500rpm as per the Merc guidelines. VERY strong motor. This motor originally came off of a 21' pontoon boat and was fitted with an 11" prop with a 9" pitch. On the maiden, maiden voyage (the first maiden doesn't count because the dingaling that I am had the wiring harness positioned through the motor such that it was holding the choke open and I couldn't seem to figure it out until I got it back on the trailer. Moron, lol) the boat JUMPED out of the water and planed off instantly and when to an over rev right away with both me at 225lbs and my brother at about 190lbs. I did some research and arrived at a 10 3/8" x 13" pitch which planed of very quickly as well and gave me 27mph up from 22mph but was also go to an over rev at WOT with a full tank of fuel (6 gals), a full cooler, and just me in the boat. It was sucking fuel like crazy. So, I purchased yet another prop sized at 10" x 16" pitch and with the same load, that prop came up out of the water nicely and planed off relatively quick, used quite a bit less fuel and the GPS speed was primarily around 29 and hitting 30 periodically. There would be moments of sputter at the top end of the revs but nothing that held and it went back to feeling as if it was pushing a load. It's important to mention, I do not have a tach in this boat and the rpms at this point is by feel and what I have heard from the sound and pitch of those vids I have been able to hear of these motors running optimally. I have a pretty good sense of the sensitivities of pushing a motor and can tell when a motor is being pushed. But to be sure I will be getting a tach installed very soon. I just like the naked look of the dash.
So here are the questions:
Do you think it would make sense to go and get another prop going up to say, a 17" pitch and verify that it can take it without dogging the motor at this point? With the 16" pitch it does still plane off quickly enough to not be dogged down in any way so will one more inch make that much difference? The fuel consumption has gone way down but it is still drinking a bit more fuel than what I was told to expect out of this motor on average. Would one more inch of pitch possibly make it hit a sweet spot in that department and increase efficiency of MPG/GPH?? Secondly, does anyone have any experience with a somewhat relative boat size motor set up and feel that that peak of 30mph is what should be expected of this set up with a nominal load on moderate to smooth water conditions on a freshwater river??
Thanks in advance for your help!!!
Back to the topic at hand, props.
I am sure that this topic has been beaten to death many times but I just need to hear it as directed at my specific situation. The boat is a 1964 14' Arkansas Traveler (very cool little old boat) fitted with a 45hp Mercury Classic 50 2 stroke 4cylinder outboard that revs at an optimal WOT range of between 5000 and 5500rpm as per the Merc guidelines. VERY strong motor. This motor originally came off of a 21' pontoon boat and was fitted with an 11" prop with a 9" pitch. On the maiden, maiden voyage (the first maiden doesn't count because the dingaling that I am had the wiring harness positioned through the motor such that it was holding the choke open and I couldn't seem to figure it out until I got it back on the trailer. Moron, lol) the boat JUMPED out of the water and planed off instantly and when to an over rev right away with both me at 225lbs and my brother at about 190lbs. I did some research and arrived at a 10 3/8" x 13" pitch which planed of very quickly as well and gave me 27mph up from 22mph but was also go to an over rev at WOT with a full tank of fuel (6 gals), a full cooler, and just me in the boat. It was sucking fuel like crazy. So, I purchased yet another prop sized at 10" x 16" pitch and with the same load, that prop came up out of the water nicely and planed off relatively quick, used quite a bit less fuel and the GPS speed was primarily around 29 and hitting 30 periodically. There would be moments of sputter at the top end of the revs but nothing that held and it went back to feeling as if it was pushing a load. It's important to mention, I do not have a tach in this boat and the rpms at this point is by feel and what I have heard from the sound and pitch of those vids I have been able to hear of these motors running optimally. I have a pretty good sense of the sensitivities of pushing a motor and can tell when a motor is being pushed. But to be sure I will be getting a tach installed very soon. I just like the naked look of the dash.
So here are the questions:
Do you think it would make sense to go and get another prop going up to say, a 17" pitch and verify that it can take it without dogging the motor at this point? With the 16" pitch it does still plane off quickly enough to not be dogged down in any way so will one more inch make that much difference? The fuel consumption has gone way down but it is still drinking a bit more fuel than what I was told to expect out of this motor on average. Would one more inch of pitch possibly make it hit a sweet spot in that department and increase efficiency of MPG/GPH?? Secondly, does anyone have any experience with a somewhat relative boat size motor set up and feel that that peak of 30mph is what should be expected of this set up with a nominal load on moderate to smooth water conditions on a freshwater river??
Thanks in advance for your help!!!