Question for "the machinist"

OptsyEagle

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or anyone else that knows.

I have a 1976 15 Hp Evinrude that has a fair bit of slack in the twist grip of the tiller arm. I can pretty much go from "shift" to "start" without advancing the throttle at all.

In LeeRoys Ramblings it says
http://www.sschapterpsa.com/ramblings/Johnson_9.9_troubleshooting.htm

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"Again for the early motors up to 1987, if the twist grip throttle handle (steering grip assembly) has developed enough slack that it is hard to find your position except if you move it from one way all the time. Or the engagement gears on the control gear & bushing assembly (#65) & the vertical shaft (#108) allow the gear teeth to jump out of mesh to where you may not be able to rotate the twist grip, you may need to make some shim spacers. These shims can be made from the plastic of the sides of milk jugs, margarine tubs or other plastic bottles.

If the throttle twist gears disengage, (#65 & 66) you may be able to place a spacer on the twist grip shaft between the end gear & the housing, pushing the shaft rearward. This can be performed without tearing any major parts of the motor apart. If this does not help & the gears still jump the teeth & get out of time, then it is time for a new shaft with the new gears, price of $46.70 for both it & the matching nylon bushing. You can weld new teeth back in or add bronze or silver solder to the tips to give more positive engagement. The newer parts have both bronze teeth as compared to sintered steel, nylon or aluminum for the older units. "

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My question is where exactly would these spacers go. Would it be like between #64 and #67 or perhaps under #109. I am a little of confused with the suggestion. Also, how thick, approximately will these spacers be and do you think that it might help reduce the slack that I have mentioned?
 

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bktheking

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Re: Question for "the machinist"

They go between the lower cowl and the throttle handle. You need to remove the handle , there is a through bolt and nut that keeps the handle attached to the motor. In your pic there is a big washer without a number, that is where the "extra" spacer is needed however:

I don't think this is your problem, all this will do is make more of a positive mesh on the tiller gears. What you are talking about is entirely different. You may have a worn set of gears which will either require a new set or repair by brazing and filing or wear somewhere else, possibly the plastic gear that sits down in the cowl or the bar that connects the plastic gear i'm referring to to the magneto plate.

I'll add- if this is somehow causing the motor to run bad or not achieve top speed by all means fix it. If it's just a bother and doesn't hinder the performance of the motor well guess what, the older 15's / 9.9 are almost all like that and to get them perfect is very expensive.
 

OptsyEagle

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Re: Question for "the machinist"

I just thought perhaps there might be a simple fix for it. I don't think it will hurt performance any. It is a little annoying but certainly manageable. Thanks for your thoughts.
 

bktheking

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Re: Question for "the machinist"

No problem, it's more of a wear and tear thing. My 76 15's gears are like new yet I still have the slop the same as you, it's just part of the old motor syndrome.
 

the machinist

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Re: Question for "the machinist"

The spacers would go UNDER the 109 gear. Since these are bevel gears & IF they are contributing to the sloppyness, you can raise the #109 by shimming under it, which pushes it up & tighter to the horizontal #52 gear.


However if the slop is in the meshing teeth of the tiller handle, I have again used plastic off margarine tubs & made a washer that can be put on the geared shaft so it fits forward of #66 & against the housing. This shaft & gear are spring loaded inside the twist grip so when shimming here it pushes #66 tighter into #65 gear.

However typically these are originally sloppy & most people learn to live with it, you just have to remember to always move the twist grip one direction to get your speed, (usually from slow to fast). You might even have to remark the START position with a felt marker. These motors will not start if the throttle is slower than needed , but will start if faster.
 

OptsyEagle

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Re: Question for "the machinist"

Thanks machinist. That clears it up for me. I will see how much it bugs me if/when I get this motor working well.

Thanks a well for all your work on your website. It has provided me with immense help.
 

OptsyEagle

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Well, better late then never. I am again looking at trying to reduce the slop in my throttle control. It does appear that gear #66 does not fit up tight to gear #65 and would like to shim it but I can't see where a shim would go that would tighten up the messing. It seems to me that the #66 shaft position is defined by the screw that holds it into the twist grip and that gets positions with a few things but the #60 seems to hold it into a constant position.

Anyone know if there is a way and where to shim this mechanism to make #66 push into #65 a little more. Could use about a millimetre or two forward on #66.
 

racerone

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A simple matter of looking at the parts.-----Perhaps make washer #64 thicker.
 

oldboat1

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Maybe the spring (66) has gotten lazy. Might try stretching it out a bit and see if that makes a difference.
 

racerone

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Springs do not get lazy here.-----Perhaps the plastic bushing / sleeve #55 is compromised.-----Very easy to shim this up to correct the issue.
 

oldboat1

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So there's a joke about a new Rolls Royce owner who has the misfortune of a broken suspension spring. After trying for six months to obtain factory assistance, he finally gets a terse letter: "Rolls Royce springs do not break."
 
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