Evinrude 75 Problem

[richpaladino]

Help. I am a new owner of an old pontoon boat and don't have any experience with motor maintenance. These are the symptoms I am dealing with.

The motor always starts and idles fine, the difficulty is in the ability to get the engine rpm up to high levels. When transitioning to higher rpm the motor always begins to bog down like it is getting no fuel. If I hit the choke during the transition it will immediately respond to higher rpm's, but never really seem to get to the max rpm, and then will begin to die out again. If I hit the choke again it begins to speed up and the cycle repeats.

Filling the tank completely full of gas seemed to make things better but still didn't get to the full rpm, or stay there.

At one time, getting the prop out of the water and reving it up to full rpm and then putting the prop back in the water would fix the problem for a while.

I changed the plugs but that didn't seem to make any difference.

It seems like it must be a fuel problem or something similar to a timing advance problem.

Any recommendations on what potential simple fixes to this problem may be that I could try. Or easy parts that I could exchange? One individual mentioned that it could be the "stator" which is under the flywheel so that would require hundreds of $$$$ to fix.

Any help would be appreciated.

 

[F_R]

Re: Evinrude 75 Problem

Since choking "fixes" it, your carburetor (or carburetors) is obviously partially plugged up. Especially the high speed orfice jets. Thoroughly clean the carb(s) and put in repair kits. Pay particular attention to those high speed jets.

 

[cuzzx]

Re: Evinrude 75 Problem

I have the very same motor on my Toon and have had similar problems, What I have found is that there is either trash or a small amount of water in your gas tank. They make items that you can get at WalMart or your local gas station that will help remove water. If this does not work then you are in for a rebuild.

 

[Evinrude Boater]

Re: Evinrude 75 Problem

FR, doesn't an air leak in the carb result in the same symptom? I took my boat out today for the last ride of the season and it was doing the same thing. I had to baby it to gradually get it to WOT. Even after it was warmed up it wouldn't respond right out of the hole. It was surging when backing off the throttle too.
When I flipped the choke on to start it I noticed fuel leaking around the big welch plugs on the front. I think I have to redo all the plugs to tighten it up.
I thought maybe the plugs were loaded up during the warm up since I mixed a tank of 25:1 fuel to try . After I pulled the boat out of the water I checked the plugs and they were toasty tan. That extra oil will probably be good for the insides during winter storage, that's about all.
Oh, and richpaladino, don't rev you engine out of the water. You'll cook your water pump in about 5 seconds and your engine in the next few minutes.

 

[1730V]

Re: Evinrude 75 Problem

Rich or lean (probably lean) the carburetors need to be serviced. I assume you're talking about carb. core plugs? Those plugs come in the OEM kits.

An easy winter project. She'll wake up fresh, in the spring.

 

[kenmyfam]

Re: Evinrude 75 Problem

Fuel pump and carb service would not be a bad thing to do.