1978 9.9HP Evinrude question

[JohnsRude]

I have the subject motor and am doing a little refurb and trying to remove the vertical control shaft gear and the inner control shaft gears to replace them. It appears that the vertical control shaft gear needs to come out first so the inner control shaft gear can slide out of it's housing. The exploded view shows a pin that the vertical gear sits on. Is anyone familiar with this and if so, will you tell me how to get it out?

 

[JohnsRude]

Never mind, I figured it out. For those that encounter this in the future on Johnson/Evinrude 9.9/15 HP 2 stroke outboards in the future (at least those models with these gears in the throttle control), the vertical control shaft gear has what should be called a plastic bushing that holds it in place, not a "pin" as listed in the parts list. it has a flange on one end and a hole through the center. I was able to remove it by making a hook using some baling wire (yes, baling wire) and pulling straight up. The gear and bushing came out, allowing the inner control shaft gear to be pulled out of it's housing.

 

[JohnsRude]

.... and for those who wish to purchase the patent pending tool I designed for the bushing removal, they are on sale in the lobby for the low, low price of $3,000 US or whatever the current retail price of a Tohatsu 9.9 hp, 2 stroke motor is.

 

[OptsyEagle]

What are you trying to fix? My motor has a lot of play in the throttle before it moves the armature plate that pushes the carb butterfly. The twist grip probably moves almost 3/4 inch each way before the throttle cam actually moves.

Did your motor have any play in the grip and if so can you fix it if those parts are removed?

 

[JohnsRude]

That is exactly the problem I was trying to fix. When investigating this, I found that the bulk of the 'lost motion' was occurring in the two gears I mentioned. After taking the gears out, I do not see a lot of wear, but I'll report back once I get it reassembled with the new gears in place.

 

[OptsyEagle]

Thanks. It is quite annoying.

 

[JohnsRude]

I reassembled the 'drive train' with 2 new gears and cleaning everything and relubing. There is no noticeable reduction in the lost motion. Interestingly, with all these parts being plastic, one might expect more wear than if they were metal, but that was not the case here. The handle motion does not match the markings for throttle position. It is very annoying. Looks like we'll just have to live with it.

 

[OptsyEagle]

Thanks for letting us know. I have heard that it can be fixed but I have stared at it for hours and cannot really see where the play is coming from and because of that I never took anything apart. I have no idea what would look differently if it had no play in it. I assume it did not when it was first made so what has changed over the years. I can't see a little wear on a gear giving it so much slack, but if not, what does slacken it up so much with use. Quite a mystery.

 

[Nytebyte]

I found it to be the shaft that goes into the gears from the tiller handle wears. I was able to tighten mine up a bit with shims.

 

[racerone]

I would rather have that older system than the newer one with complicated / expensive cable.

 

[OptsyEagle]

I found it to be the shaft that goes into the gears from the tiller handle wears. I was able to tighten mine up a bit with shims.

Does it have to come apart for that fix. Where exactly do the shims go?

 

[Nytebyte]

It does have to come apart. After removing the shaft I cleaned it up and made shims from a aluminum can and wrapped a layer on the square ends of the shaft and reinstalled.I only had the shim on 3 sides. One side had a little bump on it to line it back up in the right place if I remember right.