Help!!! I wanna use my boat now!?

Question

i have a 1994 johnson 50 horse 2 cylinder motor. the problem is power. at full throttle the motor runs as through the timimg is too low. what could the problem be?

Answer 1

its 1994. its old.

Answer 2

i run a '79 vintage evinrude runs as good as the day it was made.  with just a little basic maintenance, that motor'll still be running after we're long gone.

Your symptom is caused by one of three things:

Low compression

Inadequate spark

Fuel starvation

  A little bit of methodical troubleshooting will pinpoint the problem.

Compression test:   PSI should be the about the same on both cylinders (within 5 or 7%), if not, post a question about troubleshooting compression problems. (compression gauge, about $25)

Spark test (not a *spark plug* test):  inline spark tester (couple bucks at a car parts store), set the gap for 7/16", clip it to the engine block, attach the plug leads (one at a time) and look for sharp blue spark while you turn the engine over with the key.  Bad or no spark on a cylinder, post a question about troubleshooting the ignition.  Spark plugs should be champion QL77JC4 gapped at .030

Make sure the fuel tank is free from water and debris, the primer bulb gets and stays firm when you pump it up, the tank vent is open and clear, and the fuel is fresh 87-octane gasoline.

Make sure the timer base moves smoothly without sticking, and the carb throttles are parallel (assuming you have a 2-carb engine).

If all this checks out, you need to rebuild your carbs.

Here's an excellent write-up on how-to:

http://forums.iboats.com/showthread.php?...

Answer 3

Pump up the fuel

Answer 4

we need a bunch more info. Did it ever run good? What size and weight boat is it on? How old is the gas? Is it vro or mixed in a can? Give it up and maybe some one will take the time to help you out for free. Or take it to the marina --where for $100 an hour or more somebody will take the hood off for you.

Answer 5

O.K., a couple of problems.

One - The motor is from 14 years ago.

Two - The motor is only 50 horsepower.

Three - It is only 2-cylinder.

So, when you kick up the motor to full throttle, the speed will definitely leave something to be desired.  I am sure that most trolling motors around today are probably faster than your engine.  If I were you, I would cough up a few bucks to get yourself a new engine.  I recommend a 4-stroke 120 horsepower engine.

I also bet that if you kick it up to full throttle too soon, you also get a h**l of an air bubble behind the prop and the RPMs soar.  Be sure that you are not trying to jam it in an instant.  Be sure that you are slowly bringing it up to speed.

Sincerley,

G.C.

Answer 6

Not sure what government cheese is talking about. Your motor should have plenty of power. But there are a lot of thing that could cause this. Carburetor, electrical, and even transmission. You do need a mechanic. I cannot TS this over the internet.