Evinrude 2hp 1981 spark gap

[psteurer]

Finally got a chance to work on this little motor that I picked up a few months ago. Compression is 95 on the single cylinder. I rebuilt the carb and still have some issues with it losing power. This motor has points and I read in the FAQ section that motors without solid state ignitions should have the gap on a spark tester set to 1/4" instead of 7/16". I get a strong blue spark at 1/4". Not very much at 7/16". Is this correct?

I am trying to isolated a loss of power issue with this motor. I rebuilt the carb but still lose power when advancing the throttle. If I choke the motor, right before I advance the throttle, I can get it to WOT. It will run forever at WOT but if I reduce the throttle down to near idle, the motor will just die. I am thinking it is starving for fuel since the plug is dry when I remove it. I did clean the fuel filter and have a strong flow of fuel from the gravity fed fuel tank. Any suggestions?

 

[Joe Reeves]

Re: Evinrude 2hp 1981 spark gap

The 1/4" gap pertaining to a spark test is correct. Set the points as follows.

(Point Setting Of Magneto Models)
(J. Reeves)

Set the points as follows. Have the flywheel key aligned with the fiber rubber portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.

NOTE: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.

(Carburetor Float Setting)
(J. Reeves)

With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

You can use either Champion J4C or J6C spark plugs gapped at .030. The J6C might provide somewhat improved performance.

 

[psteurer]

Re: Evinrude 2hp 1981 spark gap

Thanks for the detailed reply. I know a little about points but not that much so this may be a stupid question. If I have a good spark jump which I do on this motor, does that mean that the points would not need to be set? I am thinking my problem is fuel delivery and not spark related.

 

[Joe Reeves]

Re: Evinrude 2hp 1981 spark gap

Check the point setting as mentioned. If they are set at 18 or 23, you would still have spark BUT that would of course affect the timing.

 

[psteurer]

Re: Evinrude 2hp 1981 spark gap

Okay thanks. I just went through the carburetor again and gave the motor a run. It runs strong at full throttle and okay at idle. The problem is when I advance the throttle. If I pull the choke out for a second and then advance the throttle, it will go to full throttle. But if I do not do that, most times it will bog down when I advance the throttle and then just stall out. I've got the OEM manual for this little motor, so the cam is set right and carburetor correctly rebuilt.

Does this still sound like it may be point related? Reason I ask is I do not have a flywheel puller but it is something I knew I would have to get sooner or later.