1970 evinrude 115 dies high rpm

[farmuse]

I have a 1970 Evinrude 115 electric shift with 120 psi on all cylinders just rebuilt the carbs because I was having to choke it to get it to run over 3000 rpms. I have ss screws set pretty close and it
throttles up now til it gets to about 4000 rpms then it just will not come to full throttle. It sounds like it is starving for fuel. The bulb is hard so i think the fuel pump/filter is operating as it should. does anyone have a suggestion as to what might be wrong.

This is the first time I have had it out since carb rebuild. There was a lot of gum in the main jets and a piece of trash in one so I though I might have found my problem.

Could it be a timing problem? could the timing be set to far in advance? possibly retarded to much? I do not know how to check the timing on this engine.

 

[farmuse]

Re: 1970 evinrude 115 dies high rpm

may have found my problem. someone has removed the rectifier ans wired around it. The battery does not charge but it does run. I checked the voltage and it is about 11.5. that explains the slow start when initially turning the key. Will purchase rectifier and see if thsat helps.

 

[emdsapmgr]

Re: 1970 evinrude 115 dies high rpm

Typically, the fuel hose bulb will only get hard when you first prime it for a cold start each day. Once the engine is running, the bulb should get softer, but should not collapse. If the bulb stays hard, you may have a problem with the ball valves in the bulb. When you get the engine running full throttle, have a friend constantly squeeze the fuel hose bulb. This will force extra fuel into the carb bowls. If the engine runs better/faster, you may have a bad fuel pump. The fuel systems on these older engines were not built to handle today's ethanol fuels. Possible the fuel is deteriorating the bladder in the fuel pump (and the fuel hoses under the cowling.)

 

[farmuse]

Re: 1970 evinrude 115 dies high rpm

That is possible, but it is a new bulb, and new lines under the cowling and rebuilt carbs, the only thing i have not done is rebuild or replace the fuel pump. I am also missing an electrical diode and rectifier in the system. I have ordered a rectifier and will be ordering the diode if i can find it. Thanks for the suggestions and I will try to do the fuel bulb pump up next time I am out.