1974 johnson 115 running problems

[norman2013]

Re: 1974 johnson 115 running problems

the fuel pump has 3 spots to hook up a gas line. I will take off the middle on which i believe to be the output and try that

 

[norman2013]

Re: 1974 johnson 115 running problems

Which one do I hook the hose too?

 

[racerone]

Re: 1974 johnson 115 running problems

Top hose in the picture is the pulse hose to operate the pump.---Middle one is pump output.----Bottom one is fuel feed from your tank.

 

[norman2013]

Re: 1974 johnson 115 running problems

Okay, I did the fuel pump test and it seemed to be working perfect. It was spurting out a steady stream of gas for a good time. I also did a spark test with my spark plug tester and it seems that all plugs are getting good spark.

 

[racerone]

Re: 1974 johnson 115 running problems

The term " good spark " means very little to folks with 40 + years of experience.-----Does spark jump a gap of 7/16" or more------Yes or no ?---Does the timer base under the flywheel rotate when throttle is advanced ?---Yes or no.----All linkages attached on the carburetors and both carburetors open fully ?--Yes or no.

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

Have you check timing?

 

[norman2013]

Re: 1974 johnson 115 running problems

After bending the spark plug tips it reaches further then 7/16 of an inch now. The linkage is all hooked up the the carb but wasn't forcing the chock flaps all the way up but now it is. and as far as the timer base I'm not 100% what that is but i think i do and it does not appear to be moving much at all maybe a half an inch. There is a large spring holding it back. Ill attach a few pictures of what I think it is.


On this photo I think your talking about that that upper arm is hooked too

 

[norman2013]

Re: 1974 johnson 115 running problems

After bending the spark plug tips it reaches further then 7/16 of an inch now. The linkage is all hooked up the the carb but wasn't forcing the chock flaps all the way up but now it is. and as far as the timer base I'm not 100% what that is but i think i do and it does not appear to be moving much at all maybe a half an inch. There is a large spring holding it back. Ill attach a few pictures of what I think it is.


On this photo I believe your talking about what that upper arm is hooked too?

 

[norman2013]

Re: 1974 johnson 115 running problems

I pulled this arm off for inspection and all seems fine but it seems that the spring on the inside if the arm isn't making the timing thing to move forward?

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

It should move much more than that, wheres that spring originate from?

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

Disconnect that spring and retry, the return happens by a spring in the throttle arm and also from the throttle control so it looks like someones tried a bad idea on your motor.
Move the throttle forward and back and check it swings right forward and right back.
Beware that someone might of put that on as the base isnt going right back so it will then idle high if it doesnt go right back to the back position so be ready to turn it off. Mine doesnt go right back, but near enough

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

I pulled this arm off for inspection and all seems fine but it seems that the spring on the inside if the arm isn't making the timing thing to move forward?

The spring in there is designed so that it allows the top and bottom bit of that arm to move forward and reverse and be still at different times so that the carb and timing base move when needed independently,

 

[norman2013]

Re: 1974 johnson 115 running problems

Yeah i pulled off the spring holding it back and started it up and it did idle high. Im thinking with a lot of penetrating oil and some lube it might be able to work right. Is there any way to get to that timing thing better? or does it need a new spring?

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

Whats wrong with it, is it not returning back to the full stop?
If so adjust your throttle cable

 

[norman2013]

Re: 1974 johnson 115 running problems

It was pretty stiff probably from sitting for several years. Iv been working it and lubing it up! It has gotten much better! just a little more and it should be fully functional. With that moving forward properly should that power up the motor better?

 

[racerone]

Re: 1974 johnson 115 running problems

It looks as though someone was guessing on how everything moves here,---You really need to verify that maximum timing is correct and that everything moves as per design.--You risk major damage if timing is way off.

 

[racerone]

Re: 1974 johnson 115 running problems

The proper spark plug gap for a running motor is about 0.030"---------BUT the ignition system was engineered and built ( at some cost ) to be able to jump a gap of up to 1/2" or more.------So when you force the ignition to jump a gap of 7/16" or more you have done a comprehensive test of all the components !

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

Bloody oathe yes

 

[Bosunsmate]

Re: 1974 johnson 115 running problems

It was pretty stiff probably from sitting for several years. Iv been working it and lubing it up! It has gotten much better! just a little more and it should be fully functional. With that moving forward properly should that power up the motor better?

Bloody oathe yes

 

[emdsapmgr]

Re: 1974 johnson 115 running problems

Regarding the movement of the spark advance rod and the timer base. These can move slowly once the original grease dries out. You may want to pull the spark advance lever of as well as the timer base. Clean these pivot surfaces well, and install a small amout of white lithium grease. They should move very easily after that, even at cold temps.