Problem with 1979 Evinrude 55hp

[SteveandCarrie]

I have a 1979 , 55 hp evinrude and the Motor runs good as long as I am going slow but when I speed up the motor starts to rev up and down and makes the front of the boat slap the water as if the prop is slipping. I already had the prop rehubbed and that did not solve the problem. Any suggestions??

 

[oldboat1]

Re: Problem with 1979 Evinrude 55hp

sounds like the boat is porpoising. Try shifting some weight to the front of the boat and/or adjusting the trim of the motor.

 

[Joe Reeves]

Re: Problem with 1979 Evinrude 55hp

Steve.... As per one of "OldBoat1's" suggestions, move the reverse lock tilt rod in towards the boat one (1) hole.

 

[SteveandCarrie]

Re: Problem with 1979 Evinrude 55hp

No, I have electric tilt on this and it is tilted properly and the weight is correct. There is somthing wrong with the motor making the boat surge.

 

[JB]

Re: Problem with 1979 Evinrude 55hp

Hi, S&C.<br /><br />What does "tilted properly" mean?<br /><br />If, in fact, your boat is porpoising (not proven, just a suspect) it is because the engine is trying to lift the bow higher than it can sustain.<br /><br />If it is merely the engine surging you have a different problem, but if you are unwilling to take suggestions to narrow the suspects how can we help?<br /><br />In normal use the tilt is changed when getting up on plane and then again to optimize performance after plane is achieved. Are you doing this?<br /><br />Another suspect is cavitation, which can occur if the engine is set too high on the transom. Check that your anticavitation plate is even with, or no more than an inch above, your keel.<br /><br />Finally, you may have water in your fuel tank that sloshes to the pickup when the bow rises.<br /><br />Let us know what you find and if you have more questions.

 

[SteveandCarrie]

Re: Problem with 1979 Evinrude 55hp

It's not that I am not willing to take suggestions I am just stating what I have already eliminated. Alls I am trying to say is somthings wrong with the motor that makes it surge and not pick up speed. It revs up and down kinda like Whaauu - Whaauu - Whaauu - Whaauu. As if it is losing power as I speed up, but its up and down. It runs great if I run slow to meduium speed.

 

[petryshyn]

Re: Problem with 1979 Evinrude 55hp

Hello Steve+c<br />>Is this boat and/or motor new to you?<br />>Has it performed proper for you in the past?<br />>Have you tried maintaining a hard primer bulb by constantly squeezing it while this surging is occuring?<br />>Is your Whaauu - Whaauu - Whaauu consistant or intermitent?<br /><br />*Try running with the alternator rectifier disconnected(disconnect the stator leads and tape em off). If this cures it, check the rectifier for shorts

 

[Mikael-Block]

Re: Problem with 1979 Evinrude 55hp

Hello Steve..<br />Check Fuelpump ...might not get enough fuel to WOT.<br />or fuel level in cabs are to low...maybe water in cabs, try to drain them..<br />even the plugs can give problems....replace them ..if they are old...need to be change every year...<br />The iginition timming are a surce to problems..<br /><br />Tell us what you have done/checked on the engine..<br /><br />There a a lot of possibilities...not easy to solve by mail...<br /><br />mikael

 

[SteveandCarrie]

Re: Problem with 1979 Evinrude 55hp

I found a pin hole in the tube going into the fuel pump. It must have been sucking air or spitting the fuel out not allowing it to the carbs. I also put new plugs and cleaned the carbs. It runs great now. Yea!!!!!