65hp Evinrude runs rough and no power

[areis34]

Problem with engine,Evinrude 65hp 1973, runs just fine with water hose hookup. Put the boat into water and it needs full choke to run at all and there is no power. Take the boat out of water, hook up water hose and engine runs just fine. Any ideas or suggestions would be appreciated...

 

[Tinlizzy]

Re: 65hp Evinrude runs rough and no power

Check the carburetor and distributor linkage synchronization. Possible ignition timing screws loose.

Check the fuel filter screen on the fuel pump. Also remove the fuel hose from the fuel tank and blow through all passages and lines with compressed air to be sure they are open. If clogged lines are the cause of the difficulty, this procedure would eliminate unnecessary servicing of the fuel pump.

Are there any backfires?

Make sure the automatic choke is functioning properly. Possible inlet needles and seats worn or stuck. Incorrect float setting.

This is just my humble advice, but start with that.

 

[chbailey]

Re: 65hp Evinrude runs rough and no power

As tashasdaddy would say: "start with the basics, compression and spark test." Compression numbers should be within 10% of each other and spark should be jumping at least 7/16.

 

[areis34]

Re: 65hp Evinrude runs rough and no power

Thankyou your feedback......I checked what you suggested....Remember that I only have the problem when the boat is in the water. When I run engine, out of the water, connected to the garden hose everything is just fine. What could be the difference between being in the water and being out of the water?

 

[Tinlizzy]

Re: 65hp Evinrude runs rough and no power

Exhaust gas entering the carburetor will give you a loss of power. possible exhaust cover screws leaking, damaged exhaust housing seals, adapter gaskets leaking, cracked exhaust housing, or exhaust adapter to cylinder screws loose or missing.

Seeing your motor has a thru prop exhaust, when in the water the problem could be greater due to restrictions on the exhaust forcing it out thru a crack.

start with the basics first though, as recommended.

Does the engine over heat? Any misfiring? What are some more symptoms if any?

 

[darrklim2]

Re: 65hp Evinrude runs rough and no power

Thankyou your feedback......I checked what you suggested....Remember that I only have the problem when the boat is in the water. When I run engine, out of the water, connected to the garden hose everything is just fine. What could be the difference between being in the water and being out of the water?

You say you checked what was suggested, what was your compression?

 

[77Lark]

Re: 65hp Evinrude runs rough and no power

I'm not a mechanic but I recently had a similar problem except mine was accompanied by not idleing for me.

I could only start it with full choke all the time and full idle on the warm up lever. Then when throttled up it would only go about 10 MPH and not plane.
Bogg down real bad.

I'm not sure but don't run it with carb problems cause oil may not get to the engine and burn it up.

I have an 85 HP OB Evinrude I rebuilt the carbs and it ran beatuiful for 1 day. Now I have no spark. Totally differen't problem though. I'm about to post a threa about that.

It was very easy to rebuild the carbs if you have the tools. Nothing special. TAKE YOUR TIME though clean it real good. Ask if you don't know!

Good luck!

 

[evinrude 79]

Re: 65hp Evinrude runs rough and no power

i have a 1979 140 hp evinrude outboard i just got this boat and took it to the lake. it don't have the power it should. it ran at 3000 rpm at full throttle . and i was told it should be running at 5000 to 5500 rpm . i tryed to pull a tuber and it was disapointing. it was at full throttle and it moved like i was trolling. what do you fine people think this is .. i change the battery and fuel filter was full of sand so i change it and that and it seem to perform better.i mixed fuel 50 to 1 i just don't know ????? please help thanks