1973 Evinrude 115 - Fuel Starving at high RPM

[BOAH]

I have a '73 Evinrude 115 that runs great at idle and lower RPM's. When I run the RPM's up, it will usually run fine for a few minutes and then start to stall or completely stall. Sometimes it will run up to 5 minutes at high RPM's. If it starts to stall and I'm fast, I can squeeze the ball and keep it going. The ball is definitely not full when it happens. If it dies completely, sometimes I only need to squeeze it one time and it will start right back up.

I run it off of 6 gal. portable tanks which are new as well as the connections and the fuel lines.

There aren't any obvious leaks and I've looked at the filter in the fuel pump but again, nothing obvious.

After reading the threads that I could find, I'm thinking fuel pump. What do you think?

If it is the pump, I see differing thoughts on either rebuilding what I have or just buying a new one. Any suggestions on that?

Thanks for any help!

 

[ezeke]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

You may need to rebuild or replace the fuel pump - 0438559 is the current OE replacement.

You need 5/16 fuel primer bulb/line/fittings.

Have you rebuilt the carburetors and replaced the fuel lines with alcohol resistant?

 

[BOAH]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

The fuel line is new and is an Atwood fuel line and ball. All of the connections are new. I installed a fuel water seperator and I also add fuel treatment to every tank.

What is the best type of clamp to use on the fuel line? I used the solid band clamp instead of the standard hose clamp thinking that this would be stronger.

I have not rebuilt the carbs (yet)

Thank for your help.

 

[emdsapmgr]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

Follow ezeke's advice.

 

[BOAH]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

Will do. I picked up carb kits yesterday. Besides new fuel line going to the motor, now is a good time to replace the fuel lines insided the motor as well. I've noticed that the connections on the fuel lines in the motor look like they're held on with zip ties. Is that the best way to connect the lines?

Thanks

 

[ezeke]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

The ties are OK if you use the right kind, with the ramped face to fit the contour of the hose. You should have a tool to get them tight.

 

[BOAH]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

I rebuilt the carbs with new kits, replaced old fuel lines inside the motor compartment with 5/16 alcohol resistant fuel lines in the engine. I just got back from the lake. Again, it runs fine at low speeds but starves for fuel at high RPMs. Time for a pump? Can I get a rebuild kit for it or does it need to be replaced?

Also, I just noticed that when I replaced the fuel lines from the tank to the engine, I used 3/8 line instead of 5/16. Are those going to have to be replaced again?

Thanks again for your help.

 

[emdsapmgr]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

Bombardier does not make a repair kit for that fuel pump. 3/8" line from the tank will work just fine.

 

[BOAH]

Re: 1973 Evinrude 115 - Fuel Starving at high RPM

Good news! I replaced the fuel pump and it runs great. Ran it all day yesterday pulling the kids around on the tube. Everyone had a great day instead of hearing their their dad moan and groan about engine problems. Thanks for all of your help!