Trolling with main motor

[greenhornet73]

I just bought a boat with a 1995 Mercury 115 2- stroke outboard.  It has an electric trolling motor but plan to troll with my main motor for more power.  My last Yamaha 130 fouled plugs on every trip if I trolled over 3 hours.  Just curious if anyone has a merc and has had good luck with slow trolling.

[sherman brown]

i have an older merc a 1979 and i use a plate to get down to 1.8 to 2.0 and its never fouled the plugs on me. this is the old tower of power 6 cylinder which you might think would foul the plugs. but i've trolled many hrs without a problem. but i always blow it out on the way back in after a day of trolling.

[Sk8man]

I have a 2002 Merc 135 Optimax with stainless prop and it will troll down to 1.8 mph or so at about 560 rpm's but the motor is not really designed for trolling. I use it pretty much only for getting from place to place. I can use it for trolling into significant wind if I have to but if done for extended periods of time it will load up and you can tell it by the "carbon" smell when it is blown out afterward. I have a 9.8 Tohatsu for trolling and that is what I use 99.9 percent of the time and a 9.9 Johnson before that. My thinking since buying the 135 Opti and boat new is that I want to extend the life of the engine so very little trolling with it has been done.

[Bozeman Bob]

I would invest in two trolling bags ,allows you to bump your throttle a bit in most cases,thus reducing fouling along with  better steering , settles the boat right down/ reduces rocking in any direction. No affiliation,  I have the small and medium from  G2outfitters.com.  Best bags I have seen on the water . 

[greenhornet73]

Good suggestion, I had two brand new drift bags that went down with the last boat. I’m going to try a little trolling tomorrow to see how it does and will probably order a couple of bags in the meantime.  I’m hoping to replace it next season with a 4 stroke if I decide I really like this boat so I’m not worried about putting more hours on it. Thanks for all your input guys, very helpful.

[greenhornet73]

Sk8man, you mentioned your stainless prop. What is the advantage of those over the aluminum?

[sherman brown]

the things i like about a ss prop is they are more durable. i can hit a pretty good chunk of wood and all i get with my ss is a bend to the blade. just take a hammer and a board for the back side and slowly bring it back close to now. but with alum you better have a spare. a ss will get you out of the hole much better than alum. a alum will flex way out of pitch on take off where as a ss don't flex near a much holding its pitch and giving the boat more take off power. you can hit small driftwood that will require rebuilding alum and only put a small ding in the ss prop. ss just gives you better performance over an alum. plus the ss just looks much better, LOL.

[Sk8man]

Top end speed and quicker out of the hole and more durable. On the downside more expensive to  buy and more expensive to repair

[Bozeman Bob]

10 hours ago, greenhornet73 said:

Sk8man, you mentioned your stainless prop. What is the advantage of those over the aluminum?

      You should also ask what is the disadvantage. 

   Cost , usually about 4 times as much.

Hitting a rock, you may end up with a bent prop shaft $$ as there is no give compared to aluminum which would take the brunt of the hit.

Top speed is within 1 maybe 2 mph but who drives around wide open ? Cruising speed may go up by .5 mph. 

Probably take quite a few years to recuperate the extra cost to make up for it in any fuel savings from the minuscule difference in prop slip and with a new quality aluminum prop there might not even be a difference.

If I was a bit tight on cash I would lean towards using that 5-600 for gear.

Deeper pockets and mainly using it where I know I am not smacking bottom I would buy a SS. The one I run on a 15' speedboat I can feel a slight difference in it being smoother when idling out  . May be better quality control or they balance them.better.  So you have a few things to consider. 

[J.D.]

I ran a 2004 Merc 115 2 stroke years ago. The motor was a "2+2", meaning 2 cylinders shut down under 1800 RPM. It trolled like a dream. I am running a 1996 Merc 90hp. 2 stroke with oil injection I purchased new, and have been trolling with it since '96.  I use 93 octane fuel, add Sea Foam fuel additive, and use a good grade of 2 stroke oil.  I change out plugs every spring.   If you have a "2+2" motor, you're in great shape to troll with it.

[greenhornet73]

8 minutes ago, J.D. said:

I ran a 2004 Merc 115 2 stroke years ago. The motor was a "2+2", meaning 2 cylinders shut down under 1800 RPM. It trolled like a dream. I am running a 1996 Merc 90hp. 2 stroke with oil injection I purchased new, and have been trolling with it since '96.  I use 93 octane fuel, add Sea Foam fuel additive, and use a good grade of 2 stroke oil.  I change out plugs every spring.   If you have a "2+2" motor, you're in great shape to troll with it.

Awesome JD, that’s what I’m hoping for. I have company coming for dinner tonight so my hopes of fishing today were squashed but some day I will have a chance to test it out.  

[Sean Youngblood]

 I am with sk8man on this. The advantages of having a kicker motor out ways. Being able to troll with your main motor in so many ways. Better on fuel economy, less fumes, and being able to get back to port incase something happens with the main motor are my top 3. Best investment I have made for my boat and enjoyment while trolling.

[MCF]

I have trolled with multiple outboards going back to the 2 strokes of the early 80's.   Evinrude and Mercury 115hp.  With no issues. 

Where you will have problems is expecting it to idle at 700-800 rpms all day, that is just asking for it to load up so you want to be able to bump up your speed using a bag or whatever.  I can remember being told decades ago by a Mercury dealer about the guy who trolled hundreds of hours per year trolling with a 115 straight six Mercury successfully.  I also can concur with the discussion about the small kicker for trolling and as a back up.   At the end of the day, everything boils down to $$$ and what you are comfortable with.    

[greenhornet73]

I do have an electric trolling motor and would eventually like to have a kicker motor, but this boat like my last is a bay boat design with the self bailing scupper valves just above the water line. I am afraid to put a kicker on and lower the deck any more which is why I think my boat sunk last fall when my bilge failed. I need something very light weight. My 6 hp Johnson was only around 35lbs.