Looking at 8hp and 15hp 4stroke Merc

[demarko210]

today for my 23 WA as a kicker for trolling, drifting and emergency situations. I notice that some have steering arms from the main engine to steer the kicker when its underload. Is the steering arm necessary? I have been reading that the main engine can act as a rudder when submerge and running on the kicker without the steering arm.

 

[Grub54891]

I'd go with the bigger motor, more power if the weather gets bad. Yes the steering arm would be good to have, as you could be at the helm and more comfortable.

 

[Texasmark]

If you don't have the tiller attached to something, unless you have the engine to transom clamp bracket squeezed down tight (making tiller arm steering impossible when you attempt to guide it) propeller torque will turn the engine sideways and you would go around in circles.

 

[demarko210]

If you don't have the tiller attached to something, unless you have the engine to transom clamp bracket squeezed down tight (making tiller arm steering impossible when you attempt to guide it) propeller torque will turn the engine sideways and you would go around in circles.

I will be installing a bracket for it. I will see how it works without the arm and if needed I will investigate prices and installations. Thanks

 

[matt167]

Yes, my dad uses the main engine as a rudder on his boat. But currents will require him to turn the kicker from time to time to get more control ( turned slightly opposite of the current ). That would drive me nuts. I’m glad that my 25hp will troll just fine on my boat, and steering is steering

 

[Texasmark]

If you don't have the tiller attached to something, unless you have the engine to transom clamp bracket squeezed down tight (making tiller arm steering impossible when you attempt to guide it) propeller torque will turn the engine sideways and you would go around in circles.

Er-ah just noticed a misnomer: ".....propeller torque will.....". Torque is pressure (Force). Thrust is pressure in motion, aka HP.....(torque x RPM)/5252. Thrust acts on the engine position.

 

[Scott Danforth]

I usually just dropped on a lower pitch prop and idled the main motor when trolling. I could maintain 1.1 to 1.3mph trolling for walleye with the 15p, and ~2mph with the 17p

 

[demarko210]

I usually just dropped on a lower pitch prop and idled the main motor when trolling. I could maintain 1.1 to 1.3mph trolling for walleye with the 15p, and ~2mph with the 17p

My plan is to go with a lower pitch from what I have read. I will start from starch and see which way it will takes me. I was mostly seeing what other items I would possibly need in making these changes other than a few grand.

 

[flashback]

Without having remote throttle and shift I don't see the steering link being very useful unless you're in open water.

 

[demarko210]

Without having remote throttle and shift I don't see the steering link being very useful unless you're in open water.

THis would be a nice to have to control from helm but not going that route. Steering is all I need. I can change gear and rpm manually if needed. I am on the Chesapeake bay and this is mainly going to be used to troll and encase the main has some issues I can try to make it back on the kicker and not call Boat US

 

[airshot]

I have a much smaller boat ( 16' side console) I troll in Lake Erie using a little 2.2 hp kicker motor. Everyone says way to small but it works. Being a single cylinder vibration can be an issue a slow idle. Being small,cit needs tobrun 1/2 throttle or more which eliminates the vibration and that small motor is not loud, a normal conversation is not a prooblem while underway. Earlier this summer, I had an electrical short in my main engine and xame in on the little kicker. Slow, yes, about 5-6 mph in a foot and a half chop. Three mile plus ride in with kicker locked straight ahead and steered using main motor dragging in the water in neutral all the way to the ramp. Steering was far better than I thought it would be. Even thru the various canals it steered quite easily. Best part about that little motor is I can troll all day on a gallon of gas. Just some actual experience for you to consider, food for thought, hope it helps......

 

[Grub54891]

Trolling with the main engine isn't the best way to go. We've had a few that come in with shifting/running issues. Turns out the owners troll with them, turn down the idle and putz along. It carbon's up the plugs/cylinders and makes them run poorly. The one's that give them a good wot throttle run at the end of the day do ok. You can put a trolling plate on the outdrive which helps a lot, just don't forget to raise it up before throttling up!

 

[boscoe99]

Er-ah just noticed a misnomer: ".....propeller torque will.....". Torque is pressure (Force). Thrust is pressure in motion, aka HP.....(torque x RPM)/5252. Thrust acts on the engine position.

Torque is technically a twisting moment. A force at the end of a moment arm will impart torque. Expressed in pound feet for US English speakers. Not feet pounds.

Thrust is thrust. Motion is not required. Think of a jet airplane at full power with the brakes holding the airplane in position. Plenty of engine thrust. No motion

 

[airshot]

Torque is technically a twisting moment. A force at the end of a moment arm will impart torque. Expressed in pound feet for US English speakers. Not feet pounds.

Thrust is thrust. Motion is not required. Think of a jet airplane at full power with the brakes holding the airplane in position. Plenty of engine thrust. No motion

Most jet engines will overpower the brakes by a long shot. Mabey a better example...

 

[boscoe99]

Most jet engines will overpower the brakes by a long shot. Mabey a better example...

OK. Rocket engine strapped down for test purposes. Boat tied to a tree on a bank with motor running wide open. Piston engine airplane chained to tie down fittings.

 

[QBhoy]

I can steer my boat with the main engine, when the auxiliary engine is powering the boat. But only if the auxiliary is adjusted and friction set at a steering angle that’s a little offset, to counter the side it’s on and it’s affect. Only in open water though. Wouldn’t be any use in close quarters. Needs adjusting every so often too.

 

[demarko210]

I can steer my boat with the main engine, when the auxiliary engine is powering the boat. But only if the auxiliary is adjusted and friction set at a steering angle that’s a little offset, to counter the side it’s on and it’s affect. Only in open water though. Wouldn’t be any use in close quarters. Needs adjusting every so often too.

Thanks. Solid information. IF close quarters I may be able to steer from the kicker itself if I can see.

 

[Texasmark]

Torque is technically a twisting moment. A force at the end of a moment arm will impart torque. Expressed in pound feet for US English speakers. Not feet pounds.

Thrust is thrust. Motion is not required. Think of a jet airplane at full power with the brakes holding the airplane in position. Plenty of engine thrust. No motion

The motion is contained in the device developing the thrust be it a jet engine or a twisting outboard propeller. As you said, there doesn't have to be motion of the object being subjected to the thrust.......but there can be if the objects resistance to the thrust is adequate........released the brakes on the aircraft and it moves.