Lowe 1756 Mercury 50 HP Bigfoot!!!!

Burgess74

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Apr 29, 2012
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4
Alright guys I could use some help. Let me start by saying I have had a multitude boats over the last 25 years. I all but quit fishing several years ago and even went without a boat for about 5 years. I got the itch again so I purchased a 2006 Lowe 1756 Roughneck with a 50 Hp Mecury four stroke Bigfoot. I always thought that the motor didn't push the boat near as well as I thought it should. Unfortunately it doesnt have a tach, but the motor seemed extremely quiet and if it was turning the max rpms it didn't sound like it to me. I done some research and decided to put a stainless steel prop on it as every other boat I had owned previously had. It came rigged with an aluminum one. It has a 13 1/4 by 15 pitch prop on it now. Took it to the water and no difference. A friend of mine has the same boat rigged with a 50 hp Honda carburated engine. He had 5 people in it and run off and left me. Just blew my mine. Another issue that I have is that I can't use my power trim at all. If I trim the motor it starts porposing. If you cant trim the motor you can't bring your rpms up thus you don't have any top end. The prop could be incorrect. I ran the boat this weekend with just me very little gear and the best I could get was 26 on my gps with the lake glassed over. My buddy can get 33-35. I'm not looking for a mass amount of speed just want it to perform as it should. I have had this boat for seven years now. Still just like new. I went with the Mercury over the Honda because it was full injected. I had always been an OMC guy but thought I would give the four stroke a try because I spend alot of time just idling around marking structure. Is there something simple I am missing here? I am not a boat mechanic or someone that is keen on rigging and setting. Its been this way since day one. You think something was set up incorrectly. A friend of mine is going to take it to the local Mercury dealer and the let them give it a look. Any help would be greatly appreciated!!!
 

pootnic

Chief Petty Officer
Joined
Aug 11, 2007
Messages
447
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

I would of thought it would run fine with that size prop.
I know those bigfoots can spin a larger diameter prop and have a different gear ratio but still...
Has it ever worked better in the 7 years you've had it?
The aluminum prop you had was a 15"pitch or is it a new 15" SS prop,that made no difference?
The boat a tunnel hull,alot of extra weight,hows the motor sit on your boat,hull in good shape?
Again a tach is going to be your best friend,maybe a prop issue but could be afew others things also...
Alot of people like those 40-60hp mercs.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

It appears a big foot could twist a 15" up pretty good. The numbers say at 26 mph your turning about 4900 rpm
Rpm range is 5500 to 6000.From your description 4900 sounds about right.
Most be a motor or setup issue.
 

Burgess74

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Joined
Apr 29, 2012
Messages
4
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

I have spoke with some other people as well. Some say my boat was rigged with a pontoon motor. The boat has been this way since day one. It is not a tunnel hull. Hull is still like brand new, as well as the motor. I am no expert but it seems to be setting about right to me. In comparison to other boats that Ive had. Its a little sad that I have had it this long and just now decided to get it lined out. I never had a boat this small so really didn't have a good reference to compare it to. I guess I'll put a tach on it so I can get some type of starting point. The prop change that I done had no difference at all. The motor runs great. I just don't know if its a setup issue thats keeping the motor from opening up. I hate to trade it off because its still like new and I really love how the boat takes the water. But I cant see dropping a bunch of money in it if this motor isn't going to work out. Motor may have thirty hours on it. As far as a tach goes, can I hook it up with the smart craft plug by my controls. If so what harness do I need and what tach would be good. Ive worked on farm equipment and vehicles for years but I know nothing of fuel injected marine engines. Thaks for the help.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

It could be as simple as the throttle not opening all the way. If its a 4 cylinder you might not notice if it was running on 3 cylinders except for a lack of power.
 

Burgess74

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Apr 29, 2012
Messages
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Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

I'm not much on guessing. I think I'll take it and get it checked out. I don't think its down a cylinder, my guess is it was never set up right. Obviously I won't be taking it where I bought it. I was going to put a tach on it, but even if it confirms what we already think I still won't be anywhere except out some money and still have a problem. Ill let them check it out and go from there. Thanks for the Help!!!!!!!!!!!!
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

By all means take it to a well established Mercury dealer. Please let us know what they find.
Good luck.
 

Burgess74

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Joined
Apr 29, 2012
Messages
4
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

Just wanted to give everyone a heads up. Talk to the mechanic today. My boat was turning 4200 rpms. He changed to a 15 pitch aluminum prop and everything is good now. Says to the boat if trimmed to the max will turn about 5900. The max is 6000 rpms. I havent got to run the boat yet, but he wants me to test run it Saturday to make sure that I am happy. Just wanted to thank everyone for the help on this!!!!!!!!
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

You said it had a 15" prop; apparently not the case if he changed to a 15.?
 

twisted prop

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Joined
May 21, 2012
Messages
1
Re: Lowe 1756 Mercury 50 HP Bigfoot!!!!

You said it had a 15" prop; apparently not the case if he changed to a 15.?

Everything I read about the bigfoot motor it is for a high torque application ( pontoon boat),
I am currently looking for a Mercury bigfoot motor for our pontoon boat, the previous owners installed a 2005 mercury 4 stroke 40 hp, great motor but not appropriate for my application, Want to trade?
 
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