Marine: Boating, Sailing, PWC, GPS and Navigation - boat motor repair

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Ray Hitt
05-25-03, 07:24 PM
I got a 1974 Evinrude, when i start it ,it runs at full tilt. Is there anything I could do to bring the idle down, and keep it down.


Sharp Advice
05-25-03, 08:06 PM
Hello and Welcome Ray Hitt to the Do-It-Yourself Web Site and the Small Engine forum.

Although this forum does not provide service and repair advice on boat engines, the professionals in the boat forum will most likely need to know more specific information on the engine type.

Kindly use the reply button to add more details. The professionals in the boating forum, where your question will be moved to, will need to know model number and what recent repairs, if any, where made that may have something to do with the current condition or problem.

In the mean time, check for any unconnected parts or linkages on the carbs and throttle linkages. Watch the throttle cables movements while moving the throttle. The cable movement may not be equal to the throttle movement or the carb throttle plates may not be moving at all.

Obviously I have not covered all the possiblities. The boat mechanics and other resident boating professionals will offer additional suggestions, advice & help.

Check back on your question several times over the next few days for additional replies.

Ray Hitt
05-26-03, 04:46 PM
The motor type is a 25hp evinrude the year is 1974. The problem is that the linkage at the carborator is fine. The throttle is working fine. It seems to be the little spring on the side of the carborator that gives it a higher idle. For more specific location, the ckoke lever accually pushes it all the way back which chokes it. It seems not to ride back far enough. The person who I had purchased it from had said it could be the swithes on the controls but it seems their just knobs that screw in and out , positioning the throttle lever.


Sharp Advice
05-26-03, 05:31 PM
Hello: Ray

Thanks for providing the additional information.

I have combined {merged} both your postings, which are now one single thread. In doing so it keeps all questions and replies within a single posting and makes following along much easier.

Please do not use the ask a question button to add additional information or post a reply back. Kindly use the REPLY button for all further communications pertaining to this question.

I'm sure the professional boat engine mechanics will be able to help you further. Check back on your question several more times over the next few days. Holiday weekend has us out and about.

BoatMech
05-27-03, 08:21 PM
Ok, let"s all get the terminology straight.
The throttle lever twists and turns the magneto which
has a cam that opens the throttle plate in the carb.
It does this by means of a cam follower on the top of the carb.
The spring on the throttle shaft keeps the follower on the cam
and keeps them synchronized. It also keeps the idle low when
you have the throttle grip twisted to Slow.
There is no adjustment to any of this.
There is however adjustment to the high and low speed
carb orifices (orfici ?). The lower one is the high and the
upper one is for the low speed adjustment. Start with the
lower knob at 3/4 turn and the upper knob at 1 and 1/4
turns out from fully in. Dont over tighten them. The
beaks of the needles tend to seat too far if you do and you will
be looking for a new carb. Give it a try, Scott