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Davey W
Guest
Yeah I'm happy they're replacing the motor. We didnt get off to a good start. Hopefully I'll have it by Tuesday.
Ernie Roberts
Member
Here's hoping Dave your outboard runs as expected when you get it back from your dealer..
I have run nothing but 2 strokes until I finally bought a new honda 50 in 05 to put on the back of my 16' Starcraft, and I was Not happy with how that outboard changed the attitude of the hull..I ran 3 different Honda cleaver style props on it and I couldn't get the hull to stop porposing until I came across a prop man that informed me to go with a Merc prop and after trying 3 of them, that hulls rides as nice as one could expect..That 4 stroke has every bit as much power out of the hole and every where through the power band as the Merc 2 stroke I took off..i'm now sold on the 4 strokes once they are set up properly..
I'm not sure if your hull is a planing type or not, but I can tell you that last week while out on a lake in Saskatchewan hunting with my buddy who lives out there, he let me run his 14' Lund with a 9.9 Yamaha on it, and with a light load in the boat, I noticed that the engine was not running near it's ful throttle RPM, and when I mentioned it to him as we ran across the lake, he commented that it always runs that way..I told him we were going to try something, so I pulled up to the shore and broke about a 1" diameter stick off from a dead tree and put that between the transom and the outboard..that motor got up and ran like he said he's never heard before..The best test anyone can do Before they drill holes in through the transom to permentately fasten the motor is go to the hardware store and grab a handfull of paint stir sticks and put a tack on the engine..On average I have found that most 14-16' hulls will pick up roughly 200 rpm with every 1/8" wooden stir stick which therefore equates to more speed..Keep adding stir sticks until the prop either cavitates on take off or while turning, and then take that one out and measure the thickness of the sticks and cut a nice piece of hardwood to use as the shim, then bolt that motor to hull and you now have the least amount of lower end in the water...Try this out and I'm confident you will be very happy with the outcome..
I have run nothing but 2 strokes until I finally bought a new honda 50 in 05 to put on the back of my 16' Starcraft, and I was Not happy with how that outboard changed the attitude of the hull..I ran 3 different Honda cleaver style props on it and I couldn't get the hull to stop porposing until I came across a prop man that informed me to go with a Merc prop and after trying 3 of them, that hulls rides as nice as one could expect..That 4 stroke has every bit as much power out of the hole and every where through the power band as the Merc 2 stroke I took off..i'm now sold on the 4 strokes once they are set up properly..
I'm not sure if your hull is a planing type or not, but I can tell you that last week while out on a lake in Saskatchewan hunting with my buddy who lives out there, he let me run his 14' Lund with a 9.9 Yamaha on it, and with a light load in the boat, I noticed that the engine was not running near it's ful throttle RPM, and when I mentioned it to him as we ran across the lake, he commented that it always runs that way..I told him we were going to try something, so I pulled up to the shore and broke about a 1" diameter stick off from a dead tree and put that between the transom and the outboard..that motor got up and ran like he said he's never heard before..The best test anyone can do Before they drill holes in through the transom to permentately fasten the motor is go to the hardware store and grab a handfull of paint stir sticks and put a tack on the engine..On average I have found that most 14-16' hulls will pick up roughly 200 rpm with every 1/8" wooden stir stick which therefore equates to more speed..Keep adding stir sticks until the prop either cavitates on take off or while turning, and then take that one out and measure the thickness of the sticks and cut a nice piece of hardwood to use as the shim, then bolt that motor to hull and you now have the least amount of lower end in the water...Try this out and I'm confident you will be very happy with the outcome..
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Davey W
Guest
When I was an MK in the CG, I changed more Johnson powerheads than anything else. We blew 7 115hp Johnsons in one year. Honda's on the HS boats were the most reliable, Mercury never gave us much trouble, but nobody abuses motors like the coast guard lol.
Ernie Roberts
Member
And before BRP took over Johnson Evinrude, OMC had the worst junk out there. their technology never changed from the 60's to the 80's...The always looked and felt really cheap to me, but I've had my share of disappointments with Mercs too, but like anything else you can get a lemon with them all..
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Davey W
Guest
Ernie, I have an Estuary, which is a true displacement hull. I also have a power transom tilt unit from CMC. I tried every position on the trim to get it to ride right, the motor still never turned the RPMs it should.
I just ordered a high thrust 4-blade prop to try and my dealer is going to set me up with a handheld tach for my test runs as well as a few different props to try. Mercury says I should shoot for 5500-5800 RPMs when running wide open. I know just from experience as a mechanic that I wasn't turning that with the factory 9.25x9 prop. This new 4 blade prop is a 10x7 and I'll also try a Mercury 9.25x7 and a 9.25x5, but I really think the 4 blade prop in a 7" pitch will be the ticket.
I just ordered a high thrust 4-blade prop to try and my dealer is going to set me up with a handheld tach for my test runs as well as a few different props to try. Mercury says I should shoot for 5500-5800 RPMs when running wide open. I know just from experience as a mechanic that I wasn't turning that with the factory 9.25x9 prop. This new 4 blade prop is a 10x7 and I'll also try a Mercury 9.25x7 and a 9.25x5, but I really think the 4 blade prop in a 7" pitch will be the ticket.
Ernie Roberts
Member
That power transom unit sounds really cool Dave but I'm not sure if it has Vertical lift capability or not, but the less lower unit you are wetting the faster that hull will run..I can't stress enough to try those stir sticks and get that lower unit as high as possible before cavitation..Simply tilting it won't do it, but lifting it vertically will along with the right prop selection..keep us posted
are you able to get an exchange on the props from the dealer? hope so. some dealers have a prop exchange to get you into the right one.
if not I did have a similar situation with a displacement hull and a 2 stroke suzuki, I wound up buying an 4 blade adjustable prop from west marine. nylon material and it had adjustments for 5 setting of pitch. once I had that I kept fooling with the pitch until I had the right combo of rpm . then knowing the boat ran well with that diameter and pitch. I was able to buy an identical aluminum prop in that size and style.
a 4 blade alum at the pitch I needed was a custom job and it cost a bundle . but the fit was right and made rpm. so the engine was working easy. also the 4 blade helped with maneuverability at slow speeds. that hull would spin on a dime with the 4 blade. if I recall correctly the prop was made for small houseboats that are generally propelled by small outboards. yet with standard props they would not make rpm at a diameter that would allow them to maneuver at slow speeds, good luck
also, I was not bashing mercs in my previous post, just telling the truth about others experiences with them.
if not I did have a similar situation with a displacement hull and a 2 stroke suzuki, I wound up buying an 4 blade adjustable prop from west marine. nylon material and it had adjustments for 5 setting of pitch. once I had that I kept fooling with the pitch until I had the right combo of rpm . then knowing the boat ran well with that diameter and pitch. I was able to buy an identical aluminum prop in that size and style.
a 4 blade alum at the pitch I needed was a custom job and it cost a bundle . but the fit was right and made rpm. so the engine was working easy. also the 4 blade helped with maneuverability at slow speeds. that hull would spin on a dime with the 4 blade. if I recall correctly the prop was made for small houseboats that are generally propelled by small outboards. yet with standard props they would not make rpm at a diameter that would allow them to maneuver at slow speeds, good luck
also, I was not bashing mercs in my previous post, just telling the truth about others experiences with them.
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Davey W
Guest
Ernie, not sure I understand the paint stick trick. Are you putting them under where the motor sits on the transom? The height of the motor on my transom is where it should be according to Mercury and the dealer. The cavitation plate is just a tick below the hull. I can't run with the motor trimmed all the way down, it puts the motor too low in the water and while it lowers the bow, it creates drag that slows the boat considerably. I with the motor trimmed down to the point where the cowling is level with the water, again how Mercury recommends. The Estuary is a 15kt boat according to what I've heard, I've only been able to push it to 12 and thats empty.
Tom, I have a good relationship with my dealer. For those in Central Jersey and own a Mercury, N&B marine in Bordentown is the best. I love those folks there...so helpful and they're honest in what they do. They're going to lend me props to try and even they're handheld tach. They really take care of their customers. As far as props, people underestimate the importance of prop selection, especially on heavier boats. Not turning enough RPMs or turning too many can shorten the engine life and cause internal parts to fail. Solas designing this high thrust prop specifically for heavy boats with small motors and kicker motors. So hopefully it'll push me up to 15kts and run right in the proper RPM range. We'll see!
And yes, every manufacturer, I don't care if its Ford, Chevy, Dodge or Mercury, Yamaha, Johnson...they will all get their lemons. I'm partial to Mercury because I learned how to rebuild them when I was 15. I've never had a Merc leave me stranded on the water...can't say the same about Johnson/Evinrude.
Tom, I have a good relationship with my dealer. For those in Central Jersey and own a Mercury, N&B marine in Bordentown is the best. I love those folks there...so helpful and they're honest in what they do. They're going to lend me props to try and even they're handheld tach. They really take care of their customers. As far as props, people underestimate the importance of prop selection, especially on heavier boats. Not turning enough RPMs or turning too many can shorten the engine life and cause internal parts to fail. Solas designing this high thrust prop specifically for heavy boats with small motors and kicker motors. So hopefully it'll push me up to 15kts and run right in the proper RPM range. We'll see!
And yes, every manufacturer, I don't care if its Ford, Chevy, Dodge or Mercury, Yamaha, Johnson...they will all get their lemons. I'm partial to Mercury because I learned how to rebuild them when I was 15. I've never had a Merc leave me stranded on the water...can't say the same about Johnson/Evinrude.
Ernie Roberts
Member
Yes Dave, the stir sticks go in between the mounting bracket and the top of the transom. although the cavitation plate is just under the bottom of hull, the more you can get it out of the water, the less drag you'll have and the easier and faster it will spin the prop..set the trim to about the middle position as a start and shim that motor and you'll be very enlightened once you find it's right height with the shim sticks..see if you can get that Tach, and give those sticks a try Dave, it will make you smile when you watch the revs come up with every 1/8" shim you add amigo..
regarding props and my dealer up here, they were good enough to bring in the prop we picked from the catalogue and if it wasn't the right one, all I did was pay for the return shipping, which I was ok with..
regarding props and my dealer up here, they were good enough to bring in the prop we picked from the catalogue and if it wasn't the right one, all I did was pay for the return shipping, which I was ok with..
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Davey W
Guest
Ernie, don't you have to worry about cavitation and prop ventilation though by raising the motor? Especially on a displacement hull boat, you don't want the prop to be caught in the hull wake. You can get slippage, lack of ventilation for the exhaust and cavitation, which can affect the motors ability to run cool. I understand we're only talking an 1/8" but I can't see that little bit doing much, other than being a pain in the arse to keep taking the motor off and on.
Ernie Roberts
Member
Hi Dave; Yes cavitation and slippage is the most important while setting up the motor to the hull for optimum performance..that 1/8" makes the difference between slipping and grabbing hard water..Once you get it raised to the point where it starts to slip, remove that last stick and measure and cut a chunk of hardwood, and set it on the transom then on goes the motor..It might sound like a pain in the butt..but I will tell you once you see how much faster and nicer everything works you wont ever run a boat motor combo without shimming things...
Something we have done on older boats is incorporate and piece of plywood on the face of the shim that hangs down over the inside transom that we will put 2 small screws into to hold it to the transom, then it's there all the time..
Something we have done on older boats is incorporate and piece of plywood on the face of the shim that hangs down over the inside transom that we will put 2 small screws into to hold it to the transom, then it's there all the time..
Ernie Roberts
Member
I had an old beat up jon boat years back that we shimmed and with 2 of us both on the back bench seat we gps-ed that hull with a merc 9.8 at 17mph..my buddy couldnt believe how fast that thing ran, and kept hounding me to sell it to him, which I did, but it was all because of that piece of wood between the transom and the outboard bracket that did it..on that hull it worked out to be a piece of 3/4" thick oak strip..
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Davey W
Guest
I'll post a picture of my transom mount and where the motor sits. I may try those wedges. The original transom mount had the motor higher and it ran much worse.