115hp Johnson Tracker Problems

[bucmac79]

Hey everyone. I just bought a 92 Tracker Nitro with a 115 johnson. The biggest problem is getting on plane. This motor should have plenty of power to plane this boat. It sounds good just won't get plane until I get weight forward. So when I take off I have to stand in front of the boat. If anyone can help I would really appreciate it. I was told that the lower unit was replaced with an older one and the previous owner was told that the boat may be a little slower. Could this be the problem? Is there a fix other than replacing it again. I also am getting no power to the switches for bilge, aerator and lights etc. Anyone have any ideas?

 

[tashasdaddy]

Re: 115hp Johnson Tracker Problems

do you trim you motor all the way down when getting out of the hole? have you check compression and spark? your accessories has nothing to do with the motor. should be separate wires to battery for them and fuse panel.

 

[Joe Reeves]

Re: 115hp Johnson Tracker Problems

What are the compression readings of each cylinder?

With the spark plugs removed, does the spark jump a 7/16" gap with a strong blue lightning like flame.... a real SNAP?

What is the highest rpm reading that the boat reaches at full throttle?

If the compression and spark are as they should be, and since the lower unit has been replaced, possibly the propeller is no longer matched to the boat.

Another possibility is that the carburetors are somewhat fouled and need cleaning.

 

[bucmac79]

Re: 115hp Johnson Tracker Problems

Thanks for the help. All cylinders have good compression and excellent spark. The boat runs great after I get it planed. How could I tell if it is the wrong prop? This seems like the most logical answer to my problem. Does any one know where I might find the fuse panel?

 

[bucmac79]

Re: 115hp Johnson Tracker Problems

Do you know how I can find out if the prop is wrong?

 

[wilde1j]

Re: 115hp Johnson Tracker Problems

What are RPM's @ WOT? If not ~ 5800 RPM, prop may not be right.

 

[bucmac79]

Re: 115hp Johnson Tracker Problems

About 5200 and 43mph

 

[wilde1j]

Re: 115hp Johnson Tracker Problems

You need at least 2" less pitch, assuming the setup is right (motor height relative to hull bottom, etc.) 3" lower would be even better (each inch of pitch is worth ~ 200- 250 RPM). The boat will pop on plane way better with the lower pitch and your motor will have a longer life.

5200 is way too low, even though the manual may say operating range is 5000 to 5500, 5800 to 6000 is WAY better for the motor.

 

[bucmac79]

Re: 115hp Johnson Tracker Problems

Thanks for the help. Do you know how I determine the pitch?

 

[wilde1j]

Re: 115hp Johnson Tracker Problems

The prop barrel is usually stamped nnXnn ... the first number is the diameter, the second is the pitch. Also, props often are stamped in the hub area with a part number. If you know the make, you can find the pitch from the PN. As a last resort, take it to a prop shop (if you have one not too far away) ... they can use a pitch gauge to tell the pitch very easily if the other means fail.