'73 Evinrude 6hp - setting throttle grip to carb position

[ncpi]

I am getting ready to reassemble the carb to the motor after cleaning/rebuilding, however I know the throttle grip wasn't matching the correct carb butterfly position when I took it apart. Someone had marked a different start position on the tiller arm instead of where the decal shows "Start". Whats the best way to get this aligned properly?

Thanks in advance for the help!

 

[Willyclay]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

I have the same motor and the factory service manual. Will try to get what you need if one of the other members doesn't beat me to it.

 

[F_R]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

The wording on the twist grip rarely matched reality even when the motor was brand new. People just had to get used to it. Having said that, if it is way off, the bevel gears may be assembled wrong, or the nylon pin in the lower end of the vertical throttle shaft may be broken. I've even seen the vertical shaft twisted because somebody horsed on it too hard, trying to make it go faster, I guess. I've also seen people attempt replacing the gears on the two tiller shafts, which you are not supposed to do. The gears are drilled and pinned to their original shafts and usually won't align if installed on another shaft.

 

[ncpi]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

...I've even seen the vertical shaft twisted because somebody horsed on it too hard, trying to make it go faster...

I could see that! LOL

Good to know I am not supposed to try to re-set the bevel gear on the shaft to get it aligned. I wondered whether I could do that with the twist grip on the shaft? Also wonder if the bevel gears possibly "jumped a tooth" or something.

I guess I just need to see if the butterfly is fully opened when the grip is turned all the way. Anyone know the position of where the carb lever should sit on the cam when it is set to "Start" or how far open the butterfly should be for "Start"?

 

[Chinewalker]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

If the gears are aligned (both sets) and nothing else is broken or bent, it is as aligned as it's going to get. Everything goes together (correctly) only one way. Not really much else to do beyond that, outside of setting the throttle pick-up to meet the cam at the marked point.

 

[Willyclay]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

Since you have two of the forum guru's posting in your thread, I will not attempt to add anything except the link below to an online parts reference and a note from the service manual that says; "Align throttle shaft gears so that the large cogs mesh." If you disassemble the throttle control handle/grip, then some other issues might need to be addressed. Good luck with that great old motor!

http://www.marineengine.com/parts/j...manufacturer=Evinrude&section=Exhaust+Housing

 

[ncpi]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

If the gears are aligned (both sets) and nothing else is broken or bent, it is as aligned as it's going to get. Everything goes together (correctly) only one way. Not really much else to do beyond that, outside of setting the throttle pick-up to meet the cam at the marked point.

Thanks everyone for your help!

What is the proper way to adjust the throttle pick-up (I assume this is the nylon lever on the carb that actuates the butterfly) to the cam for the "start" position? BTW, when the throttle is wide open, the throttle pick-up is on the highest point of the cam so I am thinking this is probably adjusted correctly, but thought I would check. I am thinking everything is set up properly and only the label is way off...sounds like that is somewhat typical.

 

[Chinewalker]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

THe cam on the underside of the mag plate has one oblonged bolt hole for adjustment. Loosen that bolt (one closer to the low speed pick-up) and adjust accordingly.

 

[Willyclay]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

BTW, when the throttle is wide open, the throttle pick-up is on the highest point of the cam so I am thinking this is probably adjusted correctly, but thought I would check.

The "nylon lever" is called the throttle cam follower and, here's what my manual says. "Throttle valve should just begin to open when flat port side of cam follower passes mark on cam." Good luck!

 

[ncpi]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

The "nylon lever" is called the throttle cam follower and, here's what my manual says. "Throttle valve should just begin to open when flat port side of cam follower passes mark on cam." Good luck!

"Throttle Cam Follower" a name that really makes sense. That adjustment position is exactly what I needed to know. Thanks.

 

[Willyclay]

Re: '73 Evinrude 6hp - setting throttle grip to carb position

Anyone know the position of where the carb lever should sit on the cam when it is set to "Start" or how far open the butterfly should be for "Start"?

The "butterfly" or throttle plate should be fully closed in the START position. If not, the return spring may be too weak and should be replaced OR the linkage is binding. FYI, these motors start and run off-idle with the idle/slow-speed mixture only. The high-speed jet is activated after substantial ignition advance occurs. Hope this helps!