Annoying Throttle Cam - 15Hp Evinrude '76

[Rick.]

Re: Friction block & spring in throttle grip

Re: Friction block & spring in throttle grip

Rick, are you SURE your friction block is in place? Along with the spring, it creates a lot of tension with the twist grip, so it shouldn't move at all when you let go.

Yes I'm certain they are both in place. I remember asking this same question when I first got this motor and the consensus was it is supposed to return to idle if you let go. Rick.

 

[Chinewalker]

Re: Friction block & spring in throttle grip

Re: Friction block & spring in throttle grip

Also, your throttle slowing down has nothing to do with the throttle cam - simply not enough twist in the carb spring to push it back that forcefully.

 

[ChrisAG]

Re: Friction block & spring in throttle grip

Re: Friction block & spring in throttle grip

Yes I'm certain they are both in place. I remember asking this same question when I first got this motor and the consensus was it is supposed to return to idle if you let go. Rick.

Whoever told you that was mistaken - the whole purpose of the friction block is to hold the throttle in the position you set it, no matter the speed. Looks like yours is missing (or installed incorrectly, e.g. without the spring). Only one way to find out: remove the grip and check.

 

[OptsyEagle]

Re: Annoying Throttle Cam - 15Hp Evinrude '76

I checked my tiller grip and it had nothing but the #62 screw that holds the handle on. Nothing else inside it. Since I doubt OMC designed it with all those components( friction block, throttle control plate, spring, washer and control shaft bushing) for no reason at all, I am leaning towards ChrisAG being correct on this one. I have ordered the above parts and will hopefully know for sure by the end of this week.

The only other concern I have now is jmendoza's comment that perhaps I also have a throttle cam for a remote control motor that might also need to be replaced since my is now tiller. The only reason I am doubtful of this is because when I look at the part number that is written on the cam I have, it is the same number as the one that is specified on the BRP parts diagram. I agree the design looks a little wierd but who am I to tell OMC how to design a throttle cam. The other wierd thing is when I looked at the part number on the throttle cam from my 1975 9.9Hp motor, it is actually the cam specified for a 1974 9.9Hp motor (318952) not the 320434 that the 1975 9.9Hp diagram's specify. I would sure like to know what the 1975 cam looks like (320434).

Anyway, I will let you know how the new parts effect my 15Hp motor and hopefully put this issue to rest. Thanks for all your help.

 

[ChrisAG]

Re: Annoying Throttle Cam - 15Hp Evinrude '76

You have the cam for the remote throttle control, change it to the one that is like the earlier 1975.

This seems off to me.

Why would there be a different cam for remote controls? I used a remote control kit for two years on my 1978 Johnson 15. It did not contain a different throttle cam. Perhaps you are thinking of the 9.9hp sailing version - it makes sense that one would have some differences.

 

[bktheking]

Re: Annoying Throttle Cam - 15Hp Evinrude '76

There isn't any difference, you don't get a different cam in a remote control setup, just a bunch of brackets and such. The difference in the sail version was high thrust "reverse" from what I know.

 

[OptsyEagle]

Re: Annoying Throttle Cam - 15Hp Evinrude '76

ChrisAG, you're the man!

It works. I put in the new friction block and new spring, into my tiller grip and took the boat for a run and it worked great. I now have automated pilot operation at any throttle speed. It also got rid of some slack I had in the grip as well. The main benefit is that previously it actually took a fair bit of strength to hold it in place when I rode at higher throttle speeds. After a 1/2 hr or so this gets tiring, plus once you reduce the throttle a little, it would snap back so quickly, making the boat jerk around alot. Now it works like it is supposed to.

I never knew they made so many modificatons to a motor when they changed it to remote control. I also had to tighten up the steering tension.

Thanks again everyone.