I recently purchased a 2004 McGregor powered by a Yamaha F60. According to the literature I should be able to exceed 20MPH. Top in I'm at 3300 RPMs and 9knts. After that the motor hestitates. I took it to a dealer where he insisted the carbs needed rebuilding. Did it and it still only turns 3300 RPM at 9knts. I told the dealer I thought the prop diameter and pitch maybe wrong, he says it's right. I still think all that was wrong is that the prop diameter/pitch are wrong. I have a 13 x 15K... Does anyone out there have a suggestion or do you know of the proper prop for this sailboat and motor combination? Thanks Bob
proper prop selection F60 Yamaha
- Thread starter robertg
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Prop pitch
robertg- I have the same problem with my x/Honda50. It hesitates and backs off after 3300rpm @ about 9 mph. I think you are in target with your analysis. The answer may lie in the pitch of the prop. Your 15 seems way too steep. Mine came with a 13, so I found a used 9 and the rpm maxed out ok, but the speed was low. Now I have a 12 pitch and it is a little better but it still hesitates and reduces rpm at full throttle. It is expensive to experiment with these props. Maybe someone out there can help both of us. Your 60hp should be able to handle a little more pitch than my 50.
I am planning to lose the ballast and raise the keel and rudders next time to see what happens.
robertg- I have the same problem with my x/Honda50. It hesitates and backs off after 3300rpm @ about 9 mph. I think you are in target with your analysis. The answer may lie in the pitch of the prop. Your 15 seems way too steep. Mine came with a 13, so I found a used 9 and the rpm maxed out ok, but the speed was low. Now I have a 12 pitch and it is a little better but it still hesitates and reduces rpm at full throttle. It is expensive to experiment with these props. Maybe someone out there can help both of us. Your 60hp should be able to handle a little more pitch than my 50.
I am planning to lose the ballast and raise the keel and rudders next time to see what happens.
Re: Prop pitch
Thanks for replying. I'm seriously thinking about trying a prop thats designed for a pontoon boat. They come either 3 or 4 blade and seem to be around the 10 to 12 pitch range. It's what I would call a displacement haul type prop that might work for our type of craft. Yes it is expensive to experiement. I wrote to the factory about my problem but no one answered me back. I had a Honda powered McGregor pass me the other day. If I see them again, I'll stop them to see what prop they are turning for you. Hoefully someone will read about our situations and have a solution. Thanks Bob
Thanks for replying. I'm seriously thinking about trying a prop thats designed for a pontoon boat. They come either 3 or 4 blade and seem to be around the 10 to 12 pitch range. It's what I would call a displacement haul type prop that might work for our type of craft. Yes it is expensive to experiement. I wrote to the factory about my problem but no one answered me back. I had a Honda powered McGregor pass me the other day. If I see them again, I'll stop them to see what prop they are turning for you. Hoefully someone will read about our situations and have a solution. Thanks Bob
Prop pitch
OK, those with a Honda 50 chould see their RPMs at about 57-5800. I have two props for mine, a 3 X 10.25 X 13 (3 blade 10.25 diameter & 13 pitch in that order) My second prop that I use primarily is a Solas 4 X 11.4 X 10.5, they both get me into the 5800 RPM range but the 3 blade gets my speed a bit higher.
The 60 Yanaha should be able to swing a 14" diameter prop with about 10" of pitch.
I like the 4 blades for the extra surface area it provides for push but of course that reduces top speed a bit but I rarely use WOT. Even with a well matched prop 20 MPH is a lot to expect, the best I ever got was 18mph at the beginning of the season, very lightly loaded, no ballast, fresh waxed hull and just me as passenger weight and only one gas tank half full. Loaded for cruising I am lucky to see 12-13 MPH.
When pushing your speed beyond 6- 8 MPH one should always have all fins up! The daggerboard will act as an air foil at speed and flip the boat over.
OK, those with a Honda 50 chould see their RPMs at about 57-5800. I have two props for mine, a 3 X 10.25 X 13 (3 blade 10.25 diameter & 13 pitch in that order) My second prop that I use primarily is a Solas 4 X 11.4 X 10.5, they both get me into the 5800 RPM range but the 3 blade gets my speed a bit higher.
The 60 Yanaha should be able to swing a 14" diameter prop with about 10" of pitch.
I like the 4 blades for the extra surface area it provides for push but of course that reduces top speed a bit but I rarely use WOT. Even with a well matched prop 20 MPH is a lot to expect, the best I ever got was 18mph at the beginning of the season, very lightly loaded, no ballast, fresh waxed hull and just me as passenger weight and only one gas tank half full. Loaded for cruising I am lucky to see 12-13 MPH.
When pushing your speed beyond 6- 8 MPH one should always have all fins up! The daggerboard will act as an air foil at speed and flip the boat over.
Re: Prop pitch
Capt. Kermie, thanks for the info. I too was thinking 4 blade, a possible pontoon boat type prop because of our boats being a displacement haul. I will go on line to see how close I can get to those measurements. Have you tried pulling a skiier? I just recently bought the boat and I'm still getting use to it. I have it on a lift, but have to raise and lower the mast each time I use it because of a fixed railroad bridge. I have modified the lift system and connections some to make it easier and faster. I have found that it sails pretty true and can handle a pretty stiff breeze. Can't wait to take a trip in it... Bob
Capt. Kermie, thanks for the info. I too was thinking 4 blade, a possible pontoon boat type prop because of our boats being a displacement haul. I will go on line to see how close I can get to those measurements. Have you tried pulling a skiier? I just recently bought the boat and I'm still getting use to it. I have it on a lift, but have to raise and lower the mast each time I use it because of a fixed railroad bridge. I have modified the lift system and connections some to make it easier and faster. I have found that it sails pretty true and can handle a pretty stiff breeze. Can't wait to take a trip in it... Bob
Capt. Kermie,
That's interesting. I don't want to hijack this thread but what size engine would you need to make, say, 15mph with a family of 4 and cruising gear? It would seem that that kind of load is what a lot of people need when they buy the boat.
That's interesting. I don't want to hijack this thread but what size engine would you need to make, say, 15mph with a family of 4 and cruising gear? It would seem that that kind of load is what a lot of people need when they buy the boat.
I would speculate that the e-tec 60 may suffice, but I know of many who went with 70hp, 75hp & 90 hp engines to get their boats to plane. 15mph is only a couple more than I make with my honda and loaded for cruising so the extra 10 with a lower gear ratio on the e-tec just may provide the neccessary torque to get the 15mph. I find the honda a bit on the anemic side and would prefer something with a bit more torque. The 4 blade Solas does compensate a bit though especially at lower speeds
26X 50hp merc - top speed 7mph @ WOT
7.3 mph to be exact - as my gps says.
Ballast empty, 1 person, cruising gear, all foils up; 50hp @ WOT... no idea of rpms... haven't installed tach yet.
Should I expect more out of the old girl?
7.3 mph to be exact - as my gps says.
Ballast empty, 1 person, cruising gear, all foils up; 50hp @ WOT... no idea of rpms... haven't installed tach yet.
Should I expect more out of the old girl?
According to MacGregors advertisement, we should be seeing upwards in the high teens lower 20's with a 50...I presume that's without ballast. I have researched and with my 60 the concenouse says I should be going with a 14 x11 K prop... So That is what I'm going to purchase and try. Also for a 50 it looks like a 11 x 10 would be the logical choice. I will post my results as soon as I make my first trial with my new prop. Bob
60 e-tec
I just ran my 60hp e-tec on my Macgregor 26m for the first time. Was able to max 13.5 knots (~15mph), but only got the RPM up to 4200. Prop size is 13,5x15. Three adults, full water ballast, two batteries, 60 litres of fuel and mast up.
Will try to get a smaller prop to be able to get the RPMs up to recommended max 5500-6000.
Does anyone have first time information on what prop size is the best for this config?
I just ran my 60hp e-tec on my Macgregor 26m for the first time. Was able to max 13.5 knots (~15mph), but only got the RPM up to 4200. Prop size is 13,5x15. Three adults, full water ballast, two batteries, 60 litres of fuel and mast up.
Will try to get a smaller prop to be able to get the RPMs up to recommended max 5500-6000.
Does anyone have first time information on what prop size is the best for this config?
The right pitch is probably going to be more important than smaller size....
http://www.tropicalboating.com/powerboating/choosing-a-propeller.html
............you are headed the right direction though. I haven't seen a dyno pull on that motor, but I would guess you are at least 12-15 HP under 60 at 4200.
c ya,
Sum
http://www.tropicalboating.com/powerboating/choosing-a-propeller.html
............you are headed the right direction though. I haven't seen a dyno pull on that motor, but I would guess you are at least 12-15 HP under 60 at 4200.
c ya,
Sum
Re: 60 e-tec
After researching and entering many discussions it apears that the pitch is more important than the diameter. Concerning my T60 Yamaha, I'm installing a 14 x 11 K high thrust prop tomorrow and will send out the results in the next couple of days. This prop is designed basically for pontoon boats and large loads, it directs the exhaust away from the prop thrust thus giving it a better forward and backwards power stroke at low end and higher RPM's at WOT. If I had a F60 then I would be going to a 11 x 10 because of the gear ratio difference between the T and F. Also those with the 50 Honda's and merc's it looks like a 11 x 10 will accomplish the same thing. I wish the MacGregor plant had been more responsive to my power/prop selections questions. As long as they have been building this boat you would think they would publish a prop guide or at least advise their dealer network of the proper prop selection for each engine manufactorer and horse power range. I have contacted MacGregor dealers and have gotten a wide range of info from them concerning prop selection. The person with the E-Tec, You need to find out what the gear ratio is of your motor before you make a new prop selection. If you are turning a 2.5 to 2.8 gear,then go 13 to 14 diameter with a 10 or 11 pitch. If you are geared at 1.5 to 1.8 then I suggest a 11 to 12 diameter with a 10 pitch... again I have been researching this for weeks and have received lots of good from what seems to be very experienced boaters... to draw these conclusions. But best choice is trying out the different props until you find that right one that fits your needs and wants.
After researching and entering many discussions it apears that the pitch is more important than the diameter. Concerning my T60 Yamaha, I'm installing a 14 x 11 K high thrust prop tomorrow and will send out the results in the next couple of days. This prop is designed basically for pontoon boats and large loads, it directs the exhaust away from the prop thrust thus giving it a better forward and backwards power stroke at low end and higher RPM's at WOT. If I had a F60 then I would be going to a 11 x 10 because of the gear ratio difference between the T and F. Also those with the 50 Honda's and merc's it looks like a 11 x 10 will accomplish the same thing. I wish the MacGregor plant had been more responsive to my power/prop selections questions. As long as they have been building this boat you would think they would publish a prop guide or at least advise their dealer network of the proper prop selection for each engine manufactorer and horse power range. I have contacted MacGregor dealers and have gotten a wide range of info from them concerning prop selection. The person with the E-Tec, You need to find out what the gear ratio is of your motor before you make a new prop selection. If you are turning a 2.5 to 2.8 gear,then go 13 to 14 diameter with a 10 or 11 pitch. If you are geared at 1.5 to 1.8 then I suggest a 11 to 12 diameter with a 10 pitch... again I have been researching this for weeks and have received lots of good from what seems to be very experienced boaters... to draw these conclusions. But best choice is trying out the different props until you find that right one that fits your needs and wants.
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