2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

[shiftychevy]

Hi there. I'm a newbie on this site. I just bought a new boat, and I know nothing about props. I have a 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI. It came with a 13.25x17 black max prop. The motor has a 2.33:1 ratio.
The boat is very slow out of the hole and will only reach about 3900-4000rpm and 24mph.
I know nothing about props. But I know this is not the right one.
I need help.
Thanks in advance.
Rob.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

My max rpm is 6000rpm.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Can Anybody Help me?
Thanks.

 

[steelespike]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Hello,I think you have more issues than a prop.You have to makeup 2000 rpm
At 200 rpm per inch of pitch you would have to go to a 7" pitch.
Your 17 is very likely close to what you need. I think the motor isn't right
probably something simple like the throttle cable adjusted wrong or a plug wire off or shorted.

 

[Silvertip]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Don't be so hasty on replacing the prop. That prop should perform just fine on that particular boat. I suspect something else is amiss with the engine. The prop would have to be so very wrong to prevent seeing 6000 rpm. It would take a reduction of 10 inches of pitch to get to 6000 rpm and that simply isn't practical on that combination. Running the numbers you provided through a prop calculator says that prop is very close to proper -- showing 13% slip. That number is not ideal but nevertheless in the ball park. Speed with that prop should be in the 35 MPH range. Look for something else -- like the throttle not opening fully or the engine simply not making full power.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

It's weird because when you take it out of gear into neutral. The motor revs up fine ??

 

[steelespike]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

If you think about it all motors rev freely in neutral.

 

[BoatNoobie]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

I have a 2005 Lowe FM165. Most Lowe FM165 owners I know, have the standard motor, not the BigFoot. Mine is the standard model with 1.83 gear ratio.

I have a 10 5/8" with 12 pitch prop and I get my full 6000 RPM.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

I don't know what's wrong? I checked the throttle cable tonight. It seems fine. All the wires are on the plugs and coils.
No warning signals or alarms. The motor runs smooth no misses. How do I check to see if all the plugs are all firing?
The dealer is about 120 miles away. He wants to send me a 14 pitch prop to try. I'm stumped.

 

[steelespike]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Is the boat new ,under warantee?If you got it from a dealer its up to him to make it work right.You should do a compression check ,being carefull to ground the plug wires.
or Run the motor for about a minute and carefully feel the plugs. You could also pull the plugs noting
their location and condition.You could get a spark checker from the auto store walmart etc.
Follow the instructions to check spark.Procede carefully as improper procedure could damage the ignition system

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

The dealer sent me a new prop too try. A 14"x13 pitch. Mercury told the dealer too try the 14x13 or the 13.75"x 15 They say it will fix the problem. Mercury recommends them for the 50/60 Bigfoot.
I'll give it a try. What do I have to lose.
I'll let you all know how it works.

 

[JLeleux]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

I have a 2006 60hp bigfoot that I installed on a 19' Carolina skiff. The old 75hp motor had a 14x17" prop so I used it. The bigfoot would only get to about 4000rpm. I had to go to a 14x13" prop and now it will run between 5500 to 6000.
Good luck.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

I tried the 14x 13 prop today and it was great!! 5500-6000 rpm.
Problem solved. Thanks for everyone's help.
Rob.

 

[steelespike]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Wow its great to see a success! I guess that throws the old rule of thumb"about 200 rpm per inch " out the window.And only a 1/4" difference on the diameter.Must have something to do with that big gearcase.?

 

[Silvertip]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

But it says a lot about the lack or low end grunt on these four strokes. Once over the hump they perform ok but they sure seem to struggle getting out of the hole.

 

[shiftychevy]

Re: 2010 Lowe FM165 with a Mercury 60 Bigfoot 4-stroke EFI Need Prop advice.

Yeah it must be the big gear case. Once the rpm's come up, it works great. Even out of hole it's not bad.
But they are not as good as a 2 stroke out of the hole. But they burn 30-40% less fuel.