twist throttle

[fishie phil]

Hi Guys
Well i do have another question about my1960 Johnson seahorse 5.5
As i stated in a few of my threads i got motor ruining but found out today something I hope you all can understand.
OK when i twist the throttle and hold back the carb roller all the way open it runs perfect from slow to fast throttle
But when i let the twist throttle and carb roller do their thing rest against the brass sleeve that is on the armature plate i can not go all the way back to shift or it will die.
Could this be timing not set with carb? Also can i wire the roller all the way open and run as is?
Thanks Phil

 

[F_R]

Re: twist throttle

As you twist the throttle grip, it does two things in sync.
1. Advance/retard the spark
2. Open/close the carburetor throttle shaft.

Now, if you open the carburetor without advancing the spark, it should stall.
If you close the carburetor with the spark advanced, it should slow down but run very rough.

Your idea of wiring the carburetor open doesn't make sense. It should stall when you retard the spark.

Anyhoo, if the motor is operating normally, those words on the tiller handle are never accurate. Hopefully, the "Start" position should be somewhere near correct. The rest of them should be considered as "This-away for" and That-away for".

 

[fishie phil]

Re: twist throttle

Yes it does as you say and runs ruff but does not stall.
But if i open carb all the way nothing and as soon as i twist the throttle it goes from ideal to fast in a matter of seconds
And the tiller handle has to be on start as you stated cause it will not start until i move it close to start with carb open or shut

 

[Joe Reeves]

Re: twist throttle

There is a scribe mark on the cam that slides against the carburetor cam throttle roller. That scribe mark must be dead center of the roller when the throttle butterfly just starts to open (synchronization).

If set such as stated above, the carburetor must be adjusted as follows:


(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Now....... If you have proper compression and spark, the engine should run as smooth as ever it can be.

The markings on the tiller throttle handle.... those are not accurate and are more so a reminder of which way is fast and slow.

 

[fishie phil]

Re: twist throttle

Yes i know of the scribe mark but but i can not get their cause the engine dies before i even get close,but i will try again in a few days and keep you posted again thanks

 

[OptsyEagle]

Re: twist throttle

What Joe was saying is that you need to adjust the link and sync so that the scribe mark is in the center of that roller JUST as the roller hits the throttle cam (your brass sleeve as you put it). If it does not, and the motor does not need to be running to test this, there are two nuts on the starboard side of that throttle cam that you loosen and then adjust it so that it does sync up properly with the carb roller.

Make sure you do not have your choke engaged when you are checking and adjusting this.

 

[fishie phil]

Re: twist throttle

What Joe was saying is that you need to adjust the link and sync so that the scribe mark is in the center of that roller JUST as the roller hits the throttle cam (your brass sleeve as you put it). If it does not, and the motor does not need to be running to test this, there are two nuts on the starboard side of that throttle cam that you loosen and then adjust it so that it does sync up properly with the carb roller.

Make sure you do not have your choke engaged when you are checking and adjusting this.

Yes i just went out and checked again and i noticed that the mark and the roller are way to far apart even if i can ajust the plate the roller would be way to far away from mark.
Could i have brass plate on wrong?

 

[Joe Reeves]

Re: twist throttle

Do you have the choke lever pulled out? That would cause the throttle roller to pull away from the cam.

 

[F_R]

Re: twist throttle

Yes i just went out and checked again and i noticed that the mark and the roller are way to far apart even if i can ajust the plate the roller would be way to far away from mark.
Could i have brass plate on wrong?

I dunno, did you have the brass plate removed for any reason?

 

[OptsyEagle]

Re: twist throttle

Can you take a picture?

 

[fishie phil]

Re: twist throttle

No coke all the way in,I will work on it later in the week and get you an update
Yes will get a picture for you,and yes i had the brass plate on and off a couple times when i had to replace the admiture plate at the beginning