View Full Version : 115 HP Yamaha stallssafe mode above 3300 RPM

07-17-2009, 06:31 PM
"1991 two stroke will run all day below 3300 RPM. If I go above, it sputters and goes into what I think is safe mode(idle which it runs fine). After about 30 seconds it will let me get back on a plane and runs great as long as I don't go over 3300 RPM for 3-5 minutes.

The following work was done by a outboard mechanic..a bit of shade tree though...

Oil tanks are full, both primary and on the engine.
Replaced thermostats.
Replaced water pump(plenty of non hot water coming out of pee hole when the trouble happens)
Replaced sensor in primary oil tank
Even swapped the computer
Replaced temp sensors
Plugs are good.
Note*The digital tilt/trim, oil level(shows full all the time) do not work on the electronic gauge. However, on the same gauge, the RPM, hour, trip and time do work.

I appreciate any help."

07-17-2009, 07:03 PM
ding dangit...I mean't 2001 year model...

07-19-2009, 08:40 PM
You seem to have exactly the same problem I have.(see my 7/16 post). I haven't had any success trying to fix it and my frustration grows. there is a good yamaha mechanic here but he is too busy to get to my boat for a month and every suggestion he has given me over the phone hasn't worked.
Nick has posted a suggestion that I should check wiring for corrosion and bad grounds. I haven't had time to do that yet but will do it in the next few days and will post results.
If you find anything that works I will be most interested and will share anything that I find out.

07-23-2009, 08:56 AM
I looked for bad connections as suggested by Nick. I found one negative wire that seemed maybe a little loose and secured it. Don't know if that was helpful or not but I moved the wires around as I searched and that may have helped and now have taken two long cruises at high rpm's without getting an alarm. It could just be playing possum and I might be back where I started when I go out again. I'll let you know. Joe

07-23-2009, 03:42 PM
"has to be a fuel delivery problem. check fuel pumps,carbs/injectors for trash/restrictions. Good luck!"

07-28-2009, 06:50 AM
Would a fuel delivery problem cause it to go inti alarm? I can see how that would interfere with high rpm operation but am not aware of an alarm associated witha fuel delivery problem.

I have not been able to cause my motor to go into alarm after several deliberate attempts since I fooled with the wiring. I still don't know if that helped or it's in remission but I like it.

07-31-2009, 06:36 PM
"Thanks to everyone for the comments and suggestions, keep them coming. I will look for bad wiring. I will post the resolution when I find the gremlin. By the way, I never actually get an audible alarm, it just reduces RPM to <~800...thanks for looking!"