I hit my last prop on rocks last october and bought a replacement, going up one pitch from 14x10 to 14x11
On the cruise from Oak Orchard to WIlson NY (35 miles)
Crew weight of 600 pounds plus another 200 pound of gear for a week cruise
Unballasted I report 9.6 mph at 3000 rpm and 7.2 mph at 2000 rpm
Fuel economy might be down a bit, I havent refilled yet but consumed the 12 gallon main on an estimated 55 miles total (I usually cant get the last 2 gallons out without tipping.
With ballast in, speed at 2000 rpm drops to 6 mph.
I havent tried the WOT rpm yet and have a question. If I cant reach the 5500 recommended by the Mercury I am 'overpropped'
If I never intend to use the motor WOT, am I still lugging the engine to damage point driving the higher pitch prop at 2000-3000-4000 rpm? Intution say no, but my intuition also said I could sail in 8 footers on Sunday..
The engine is much quieter at 2000 rpm and 6 mph is a nice cruise speed where the kids can helm, etc..
What say the motor experts??
MERC 14x11x3 prop report
comparison numbers
Please post what the same RPMs produced in speed with your previous prop so I can see the comparison. Also, with the two prop side by side how do the blade shapes and surface areas compare?
..
Technically, if you can't reach you WOT RPM range you are overpropped. But if you stay well away from full throttle I can't imagine that you would have any problem. I think most people just use the standard issue prop that came with their outboard and accept whatever the performance is without question. I rented a pontoon boat once with a Suzuki DF50 on it, it had the 13 pitch default prop and it was lugging badly and topped out around 5500 RPMs. That motor had been in service a couple years without problems.
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Technically, if you can't reach you WOT RPM range you are overpropped. But if you stay well away from full throttle I can't imagine that you would have any problem. I think most people just use the standard issue prop that came with their outboard and accept whatever the performance is without question. I rented a pontoon boat once with a Suzuki DF50 on it, it had the 13 pitch default prop and it was lugging badly and topped out around 5500 RPMs. That motor had been in service a couple years without problems.
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James V
- Admiral
- Posts: 1705
- Joined: Sat Jan 22, 2005 9:33 am
- Sailboat: MacGregor 26M
- Location: Key West, Fl USA, 26M 06, Merc 50hp BF "LYNX"
I only get 5150 out of mine with a 14 x 10 prop. My dealier Marine Max does not have a problem with this. As I read the manual, If the RPM'S was around 4000 it would be a problem.
I also found in the book that Mercury recommends to run the motor at WOT every once in a while to clean it out. This is what the motor is designed to run at.
My performance is about the same as yours.
I also found in the book that Mercury recommends to run the motor at WOT every once in a while to clean it out. This is what the motor is designed to run at.
My performance is about the same as yours.
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Night Sailor
- Admiral
- Posts: 1007
- Joined: Mon Dec 26, 2005 4:56 pm
- Sailboat: MacGregor 26X
- Location: '98, MACX1780I798, '97 Merc 50hp Classic, Denton Co. TX "Duet"
Which Merc?
You didn't say, and I don't recall which Merc you have. 2 stroke or four?. 3 or 4 blade prop?
Assuming a standard 3 blade, your reported speed per rpm is about right for being overpropped by one inch pitch if a two stroke. It's more important for the 2 stroke as it is designed to develop it's torque and hp at higher rpm and runs more efficiently at higher speeds, say around 3000 to 4000. If four stroke the lower rpm from a one inch too much pitch at WOT shouldn't hurt anything but top speed and economy at WOT because it gets higher torque at lower rpms.
Assuming a standard 3 blade, your reported speed per rpm is about right for being overpropped by one inch pitch if a two stroke. It's more important for the 2 stroke as it is designed to develop it's torque and hp at higher rpm and runs more efficiently at higher speeds, say around 3000 to 4000. If four stroke the lower rpm from a one inch too much pitch at WOT shouldn't hurt anything but top speed and economy at WOT because it gets higher torque at lower rpms.
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Terry
- Admiral
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- Joined: Thu Feb 19, 2004 2:35 pm
- Sailboat: MacGregor 26M
- Location: Vancouver, B.C. Canada. '03 26M - New Yamaha 70
SS Proops
I have always been curious as to real world results with SS props, the so called experts lay claim to superior performance due to the thinner but stronger blades, but one member here claimed lower gear case damage due to the inflexible SS prop and recommended aluminum. I use a 4 blade aluminum but I may upgrade to a 4 blade SS in the future when budget permits. Anyone else using SS props and if so what are your findings?I have a 4 stroke 3 blade SS prop.
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Frank C
I was told that stainless props have two advantages over aluminum, less blade flex and less rotational drag. Both of those advantages become really important at higher speeds than the Mac can achieve.
Three disadvantages of stainless, IMO, are cost, weight and they're probably greater thief magnets than a humdrum prop. I spent over $300 for a Solas stainless 3-blade for my Suzuki, 14x11x3, and the motor simply spins it like a dragster burn-out above 3500 rpms. Maybe that's confirmation of "less drag!" ??
Since Ace props refused to exchange it
... it still sits on a garage shelf. 
Three disadvantages of stainless, IMO, are cost, weight and they're probably greater thief magnets than a humdrum prop. I spent over $300 for a Solas stainless 3-blade for my Suzuki, 14x11x3, and the motor simply spins it like a dragster burn-out above 3500 rpms. Maybe that's confirmation of "less drag!" ??
Since Ace props refused to exchange it
... it still sits on a garage shelf. -
James V
- Admiral
- Posts: 1705
- Joined: Sat Jan 22, 2005 9:33 am
- Sailboat: MacGregor 26M
- Location: Key West, Fl USA, 26M 06, Merc 50hp BF "LYNX"
I do like my SS prop. When I have run on sand bars the blades do not get chewed up. I do not have the problem that Frank C does but I have a Mer.
I have also been told that If you hit something really hard like a tree stump, The SS prop will not breack as soon as an aluminum. This may cause damage to the trans.
I have also been told that If you hit something really hard like a tree stump, The SS prop will not breack as soon as an aluminum. This may cause damage to the trans.
Being overpropped is sort of like driving your manual transmission car one gear too high... not downshifting from overdrive to pass and starting out in 2nd gear instead of first. The difference isn't as great as that between gears, but it's the same thing. You can get away with it if you're lightly loaded and accelerate slowly with light throttle.
Many on the Whaler forum don't consider the benefits of stainless props to be significant enough to be worth the price until you get to a motor that can drive the boat faster than 30-35 mph.
Theoretically, the hub in a stainless prop will slip to protect the gears in the lower unit if you hit a stump.
Frank, check to see if there's enough overlap between the gear case and front of the prop to keep exhaust from getting through it and out forward of the prop blades. I had that problem with the Michigan Wheel 4-blade I put on the Suzuki until they redesigned the forward thrust washer, and the symptoms were the same. I was going to have the original machined to fix it if they didn't.
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Moe
Many on the Whaler forum don't consider the benefits of stainless props to be significant enough to be worth the price until you get to a motor that can drive the boat faster than 30-35 mph.
Theoretically, the hub in a stainless prop will slip to protect the gears in the lower unit if you hit a stump.
Frank, check to see if there's enough overlap between the gear case and front of the prop to keep exhaust from getting through it and out forward of the prop blades. I had that problem with the Michigan Wheel 4-blade I put on the Suzuki until they redesigned the forward thrust washer, and the symptoms were the same. I was going to have the original machined to fix it if they didn't.
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Moe
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shehzad
- Chief Steward
- Posts: 53
- Joined: Tue Aug 30, 2005 2:18 am
- Sailboat: MacGregor 26M
- Location: Karachi, Pakistan
- Contact:
I am using Yamaha 50T, 2006 with propellar 14x11 Aluminium.
In the first ten hours of the engine, I was touching 6000 RPM with the speed of 15 MPH on my GPS.
On my first service of the engine, which was done after completing first 10 hours, the RPM went down to 5500 rpm with speed to 12 mph and after that even now when I have completed more than 50 hours, I am never able to acheive more than RPM 5500, indeed with the same weight, as I had been puting before.
Recently, I have even changed the propellar with the same size, but the result is same.
Can any one please inform if this is normal ?
To me it seems, impossible to acheive the speed of 22 mph, which many people claim that they have touched.
In the first ten hours of the engine, I was touching 6000 RPM with the speed of 15 MPH on my GPS.
On my first service of the engine, which was done after completing first 10 hours, the RPM went down to 5500 rpm with speed to 12 mph and after that even now when I have completed more than 50 hours, I am never able to acheive more than RPM 5500, indeed with the same weight, as I had been puting before.
Recently, I have even changed the propellar with the same size, but the result is same.
Can any one please inform if this is normal ?
To me it seems, impossible to acheive the speed of 22 mph, which many people claim that they have touched.
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aya16
- Admiral
- Posts: 1362
- Joined: Fri Feb 18, 2005 6:29 am
- Location: LONG BEACH CALIF Mac M 04 WHITE
Props boy what a hassle, propping a boat is hit and miss, I have two identical props for the Boston whaler 14 inch pitch same brand and
One will slowly get the boat up on plane and reach 5400 rpm at 33 mph.
The other will jump the boat up on plane get 5500 rpm and 35mph.
They are new and you can guess which one I use.
Mark has been trying many props to get the performance that his Suzuki 50 should achieve. We tried them on my boat and his. My boat weighs more. He is pretty much in the ballpark with his boat but mine is a slug
with his props.
My prop that came with my boat has the numbers unreadable so marks guess and mine is its a 13 pitch. Being a 13 it should be a real dog, but it isn’t. I have hit 18mph without ballast but mostly 16-17 mph sustained at 5600rpm.
As heavy as my boat is with a 50 suz. I dont think any other prop will do better.
The performance of the Mac and they way it handles under 15mph is
marginal. It wallows and the seas push the bow around. Over 15mph the Mac planes and is a dream to handle in most seas.
The Mac seems to work great with the etech 60 13 pitch, lightly loaded boat. You dont need full throttle to get over 15mph. But the torque of the 4-stroke suz 50 with the right prop should work better on a heavy Mac.
My point: we all add stuff to our Macs. We tow dinghies, and mostly run with ballast in the tank. Macs work better with more hp. a boat the size of the Mac should handle a 200hp outboard. But with the round bottom and all the weight up top plus the thin glass Macs have to save weight would be suicide with a 200hp. A 90 is used on 17-foot boats all the time. It’s a small engine compared to v6 135 I ran on my 17-foot cuddy. But a 90 on the Mac puts it in the sweet spot with or without ballast. And doesn’t work hard to do it. So in my opinion the Mac needs at least a 60 to perform after it’s loaded up.
Macgregor and this is a guess recommends the 50 even though many 50s and 60s are identical because the boat performs ok lightly loaded.
Any more hp you get into problems in handling and slamming in large swells.
The ballast tank probably cant handle that pounding. But using the boat
with the bigger 90 in a smart way wont effect anything. Its not a speed boat or a great handler in the first place but if your goal is to keep the boat on plane without screaming the guts out of your engine the 90 is ideal. And the prop issue goes away. I bought my boat in 2004 and Im out of warranty plus there is no tag on my boat that says max hp 50. So insurance shouldn’t be a problem. So im going with a 90 soon. Because I have a use for my 50suz on my whaler Im not stuck with it.
But anyone reading this and is going to be buying a Mac for the first time
get the 60hp instead of the 50. The big foot merc 50-60 are the same engine. The etech 50-60 are the same the suz is different and 60 is larger
So thats a another story. The Yamaha is the same as the big foot merc.
A fifty will plane the boat but not as well as a 60.
I have never in 40 years of boating ever heard anyone complain about having too much power, always its not enough. The throttle controls how much hp you put to the prop. A 90 can go as slow as a 25, but a 25 cant go as fast as a 90. This boat being somewhat of a hi-bred can use a little more power to reach the goal of the factory 20mph when the boat is loaded in the real world.
As far as stainless props I never owned one, but seems that a little flex when putting the jumping up on plane would be a good thing so I dont know.
Now as someone told me last week the ideal engine for the Mac would be an older merc 2stroke 90 that weighs the same or less than a suz 50.
Now BWY doesnt recommend the etech because they quote
Many problems with them, I know 4 Mac dudes that have them and as far as I know they never had a problem. BWY do post on this board sometimes, I wonder if they changed their mind or have any more to add to what they posted on their website about the etech. My guess is that BWY tested many motors like they said and found that the 90 was the best motor, but being a dealer and Macgregor doesnt want 90's on their boats they fudged a little and said the seventy works best, That by the way is the same motor as the 90 in most cases.
I bet mac doesnt want the 90 because someone will be trying to do Jet Ski
Bat turns and the Mac will put the mast in the water causing all kinds of bad day type stuff. Or run the Mac hard in 6-foot swells and crack the ballast tank. If getting the 90 is what you want better make sure you dont abuse the boat and have that transom that you can see through beefed up a bit.
Remember the Mac is a sail boat not a speed boat and going with a bigger engine is only to achieve the recommended speed and performance
The factory states on a fully loaded boat. Not to enter the Long Beach to Catalina ski race. So if you cant control the urge to slam the Mac into 6 foot seas then get a smaller engine, cuzzzzz you will break your boat and macgregor will say see I told you so.
I realize IM long winded here but I think there are lots of folks reading this stuff we all jot down and havent bought their boat yet and I want to be specific.
One will slowly get the boat up on plane and reach 5400 rpm at 33 mph.
The other will jump the boat up on plane get 5500 rpm and 35mph.
They are new and you can guess which one I use.
Mark has been trying many props to get the performance that his Suzuki 50 should achieve. We tried them on my boat and his. My boat weighs more. He is pretty much in the ballpark with his boat but mine is a slug
with his props.
My prop that came with my boat has the numbers unreadable so marks guess and mine is its a 13 pitch. Being a 13 it should be a real dog, but it isn’t. I have hit 18mph without ballast but mostly 16-17 mph sustained at 5600rpm.
As heavy as my boat is with a 50 suz. I dont think any other prop will do better.
The performance of the Mac and they way it handles under 15mph is
marginal. It wallows and the seas push the bow around. Over 15mph the Mac planes and is a dream to handle in most seas.
The Mac seems to work great with the etech 60 13 pitch, lightly loaded boat. You dont need full throttle to get over 15mph. But the torque of the 4-stroke suz 50 with the right prop should work better on a heavy Mac.
My point: we all add stuff to our Macs. We tow dinghies, and mostly run with ballast in the tank. Macs work better with more hp. a boat the size of the Mac should handle a 200hp outboard. But with the round bottom and all the weight up top plus the thin glass Macs have to save weight would be suicide with a 200hp. A 90 is used on 17-foot boats all the time. It’s a small engine compared to v6 135 I ran on my 17-foot cuddy. But a 90 on the Mac puts it in the sweet spot with or without ballast. And doesn’t work hard to do it. So in my opinion the Mac needs at least a 60 to perform after it’s loaded up.
Macgregor and this is a guess recommends the 50 even though many 50s and 60s are identical because the boat performs ok lightly loaded.
Any more hp you get into problems in handling and slamming in large swells.
The ballast tank probably cant handle that pounding. But using the boat
with the bigger 90 in a smart way wont effect anything. Its not a speed boat or a great handler in the first place but if your goal is to keep the boat on plane without screaming the guts out of your engine the 90 is ideal. And the prop issue goes away. I bought my boat in 2004 and Im out of warranty plus there is no tag on my boat that says max hp 50. So insurance shouldn’t be a problem. So im going with a 90 soon. Because I have a use for my 50suz on my whaler Im not stuck with it.
But anyone reading this and is going to be buying a Mac for the first time
get the 60hp instead of the 50. The big foot merc 50-60 are the same engine. The etech 50-60 are the same the suz is different and 60 is larger
So thats a another story. The Yamaha is the same as the big foot merc.
A fifty will plane the boat but not as well as a 60.
I have never in 40 years of boating ever heard anyone complain about having too much power, always its not enough. The throttle controls how much hp you put to the prop. A 90 can go as slow as a 25, but a 25 cant go as fast as a 90. This boat being somewhat of a hi-bred can use a little more power to reach the goal of the factory 20mph when the boat is loaded in the real world.
As far as stainless props I never owned one, but seems that a little flex when putting the jumping up on plane would be a good thing so I dont know.
Now as someone told me last week the ideal engine for the Mac would be an older merc 2stroke 90 that weighs the same or less than a suz 50.
Now BWY doesnt recommend the etech because they quote
Many problems with them, I know 4 Mac dudes that have them and as far as I know they never had a problem. BWY do post on this board sometimes, I wonder if they changed their mind or have any more to add to what they posted on their website about the etech. My guess is that BWY tested many motors like they said and found that the 90 was the best motor, but being a dealer and Macgregor doesnt want 90's on their boats they fudged a little and said the seventy works best, That by the way is the same motor as the 90 in most cases.
I bet mac doesnt want the 90 because someone will be trying to do Jet Ski
Bat turns and the Mac will put the mast in the water causing all kinds of bad day type stuff. Or run the Mac hard in 6-foot swells and crack the ballast tank. If getting the 90 is what you want better make sure you dont abuse the boat and have that transom that you can see through beefed up a bit.
Remember the Mac is a sail boat not a speed boat and going with a bigger engine is only to achieve the recommended speed and performance
The factory states on a fully loaded boat. Not to enter the Long Beach to Catalina ski race. So if you cant control the urge to slam the Mac into 6 foot seas then get a smaller engine, cuzzzzz you will break your boat and macgregor will say see I told you so.
I realize IM long winded here but I think there are lots of folks reading this stuff we all jot down and havent bought their boat yet and I want to be specific.
Last edited by aya16 on Fri Oct 13, 2006 8:27 am, edited 1 time in total.
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shehzad
- Chief Steward
- Posts: 53
- Joined: Tue Aug 30, 2005 2:18 am
- Sailboat: MacGregor 26M
- Location: Karachi, Pakistan
- Contact:
Aya 16,
I had done the service my self as there is no real expert available in my area and at the same time, I had also changed the throtle handle because, the one came with Yamaha 50T was too big to be fixed on the steering stand.
I had also checked the throtle wire which connects with the engine. On that perticular point, it seems that on full throtle, no more space left for wire to be pulled more, even by a plier. Therefore it is confirmed that the wire is pulled to the maximum limit of the engine.
But what is the answer to the maximum speed of 22 MPH, which is far ahead of me, even at the time when my Yamaha 50T was running at 6000 rpm and still touched only 15 mph.
Is this speed only acheivable in areas of United States ? as my boat is running in the Arabian sea therefore, it is different altitude, or what else it could be.
I had done the service my self as there is no real expert available in my area and at the same time, I had also changed the throtle handle because, the one came with Yamaha 50T was too big to be fixed on the steering stand.
I had also checked the throtle wire which connects with the engine. On that perticular point, it seems that on full throtle, no more space left for wire to be pulled more, even by a plier. Therefore it is confirmed that the wire is pulled to the maximum limit of the engine.
But what is the answer to the maximum speed of 22 MPH, which is far ahead of me, even at the time when my Yamaha 50T was running at 6000 rpm and still touched only 15 mph.
Is this speed only acheivable in areas of United States ? as my boat is running in the Arabian sea therefore, it is different altitude, or what else it could be.