'91 Evinrude 20hp power surging problem!

67Mirro

Seaman Apprentice
Joined
Apr 13, 2022
Messages
41
Good day everyone!

I am having a little issue with my 20hp Evinrude 1991 power/ fuel issue.

Last week I had it at the lake for the week on my 14 ft. aluminum boat. I started it up and it ran and idled fine out of the channel until I powered up and it ran fine full throttle for the first 300 yards then it would lose power and then restore the power and speed up and slow down constantly until I got back to the next channel where it idled and putted along fine in the channel. When I got back I realized that I didn't open the vent on the tank, so I opened it and took it back out and it was still doing the same thing. So I went to pull the boat out and powered up to go to the launch and after getting on plane again it started surging almost like lack of fuel (same as before) so I was pumping the primer ball seemed to be helping it get fuel(the inline filter has little to no fuel in it all week after I fill it with primer ball after it empties to the motor it seems to run like empty) anyways then I lost all power and it would only go around 5 km/h with full throttle.

Here's what I'm thinking I'm going to be doing to it:
-Put a new primer ball in
-move my tank from the front of the boat to the back so the pump doesn't have to pull from 14 ft. away( shouldn't be that big of deal though because once the lines full it doesn't need that much pressure to pull it as its primed don't know if this will really help)
-also ordered a new fuel pump rebuild kit just incase that's the issue the diaphragm looked pretty stretched.

What's everyone's opinions on here or if they have came across this problem in the past and what should I be looking for. I also pulled a plug one didn't look the best so I'm putting new ones in as I already have a few sets.

Anything helps just trying to nail down as much as I can before I make the drive to the lake again.

Thanks!
 

67Mirro

Seaman Apprentice
Joined
Apr 13, 2022
Messages
41
Inspect pick-up tube INSIDE the tank.
did that its on good clamped it on to the pick up

also pulled the feed line off the fuel pump and primed it with my thumb over the inlet fuel line to the pump and it seemed to hold pressure great ball stayed hard and filter was full so i have a feeling it was leaking somewhere in pump
 
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