Jump to content
  • GUESTS

    If you want access to members only forums on HSO, you will gain access only when you Sign-in or Sign-Up .

    This box will disappear once you are signed in as a member. ?

Loss of Power on '79 Evinrude


MntkaFishin

Recommended Posts

I took the boat out yesterday for the second time this spring and everything was running fine, good rpms, the boat would plane nicely, so I decided to shut things off and do some fishing for about an hour. When I started her back up I noticed that at full throttle the engine would almost bog down and the power just wasn't there(ie., the boat wouldn't plane and the rpm's weren't nearly as high). Being that I'm relatively new to boat motor maintenance and this is a rather old engine, 25 HP '79 Evinrude, I'm not sure were to start. One thing I did notice is that the motor would kind of shake, almost on que, every couple of seconds. Is there a couple of simple checks a newbie could do to try and isolate the issue? I would imagine it has something to do with either a bad plug or a compression issue.

Link to comment
Share on other sites

As you mentioned I would check compression on motor, get 2 new plugs, and run a seafoam in your tank.

Read procedure on top of this page, let us know what are the reading with compression test, and we'll go from there.

Link to comment
Share on other sites

Yep could be water (Add water Remover, a bad or cracked coil, fouled plug. Make sure vent on tank is open. Look around the motor for any fuel leaks or even a clogged fuel filter. I run an inline filter on the hose.

Link to comment
Share on other sites

I took the boat out yesterday for the second time this spring and everything was running fine, good rpms, the boat would plane nicely, so I decided to shut things off and do some fishing for about an hour. When I started her back up I noticed that at full throttle the engine would almost bog down and the power just wasn't there(ie., the boat wouldn't plane and the rpm's weren't nearly as high). Being that I'm relatively new to boat motor maintenance and this is a rather old engine, 25 HP '79 Evinrude, I'm not sure were to start. One thing I did notice is that the motor would kind of shake, almost on que, every couple of seconds. Is there a couple of simple checks a newbie could do to try and isolate the issue? I would imagine it has something to do with either a bad plug or a compression issue.

interesting.

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.


  • Your Responses - Share & Have Fun :)

    • Your kid needs to stay with him!👍
    • My kid was eating in Beverly Hills and ran into this guy. Talked to him a bit and wished him luck in the game tonight.     
    • 🤔as a recovering machinist!🤣🤣that must make me a recovering welder!
    • As a recovering machinist, I can appreciate that.  If the spec is 0.001 - 0.0015, then clearly the correct measurement is 0.00125, duh…
    • I just figured that it is easy enough to just get a 3 bank so when the boat is not in use I can keep all 3 batteries charged. I have not bough a charger yet, maybe I will give it some more thought. Edit: After thinking this over, with the size, weight, and heat output of the charger (as well as the cost) I think it makes sense to just buy a 2 bank charger, I have a smaller charger i can use on the starting battery when the boat is sitting at home. Forgive me, for i am a retired engineer and I have to obsess over everything...
    • Congrats on the motor!  I think you’ll like it.   I can’t say much on the charger location but I’ve seen them under the lid in back compartments and under center rod lockers.  160 degrees is more than I expected to hear.   Curious why you’re opting for a 3 bank charger with a 24V trolling motor.  Unless you don’t feel you be running you big motor enough to keep that battery up as well?
    • I did buy an Minnkota Ulterra, thanks for the recommendations. I had a bunch of Cabela"s bucks saved up, which helped. Now i need to get an onboard battery charger. Where do you guys mount these things in your boat? The manufacturer I am looking at {Noco genius) says tht their 3-bank charger will run at 160 degrees, seems like a lot of heat in an enclosed compartment? Thanks for any input on this.
    • You're very lucky a troop of Sea Monkey's didn't carry you away.   
    • Wasn't terrible at a state park beach. Antelope island maybe.  I wouldn't recommend it as a beach destination tho.  Figured I was there, I'm getting in it.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Privacy Policy. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.