1975 Evinrude 9.9 help

tanuki

Petty Officer 2nd Class
Joined
Nov 23, 2011
Messages
137
I have a 1975 Evinrude 9.9 that ran like a top last year and most of this year. All of a sudden (when the motor is warmed up) sometimes when I restart it the motor revs up extremely fast and I have to press the shut off button to stop it. It will do this many times and I have to keep shutting it down. It almost sounds like the motor is revving faster that wot (if that is even possible). After a while the motor will start and idle properly and run like a champ again. Last time out, motor ran properly to our fishing spot?I shut it down, anchored, fished for awhile, then when we were ready to leave I started it and it revved extremely high many times and I had to shut down again. I could not put it in gear as it was revving too fast. What I wound up doing was starting it and instantly putting it in gear ( I know, not a good thing) which made the boat lunge forward at wot. Went about 100 feet forward and then the motor ran properly again. Ran properly back to the trailer and when I got home and I flushed the motor in a garbage can it started and idled like a champ. I am a rookie with the motor, but I have learned a lot from this forum and ?Leroy?s site?. Any ideas on solving my problem is really appreciated.
 

Tim Frank

Vice Admiral
Joined
Jul 29, 2008
Messages
5,346
Re: 1975 Evinrude 9.9 help

First thing I'd do is a good visual of all the carb and throttle linkages to see if anything looks loose, or if there is something that might be causing interference/jamming
 

kbait

Commander
Joined
Nov 13, 2007
Messages
2,461
Re: 1975 Evinrude 9.9 help

+1 w/Tim^. Sounds like the cam follower linkage(carb) needs to be lubed up. If it's sticky, that'll cause your symptoms. Pull the airbox and take a peek.
 

tanuki

Petty Officer 2nd Class
Joined
Nov 23, 2011
Messages
137
Re: 1975 Evinrude 9.9 help

@ Tim Frank and kbait....thank you for the info, will check next time I get to the boat and get back to forum.
 

tanuki

Petty Officer 2nd Class
Joined
Nov 23, 2011
Messages
137
Re: 1975 Evinrude 9.9 help

Update....pulled the airbox and saw nothing unusual. Looked clean and free moving. Sprayed some cleaner on the linkages and ran the motor in a barrel for 1/2 hour starting and stopping it. No high speed revving, but I will be taking the motor indoors for the winter now and do some preventive maintenance. Will clean up and lube the cam follower linkage, etc. as I tinker with the motor. At least now I know what to look for with the high revving problem. Thank you guys again for your input.
 
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