1975 25hp sneeze, and screw?

[drkilldrmz]

Hello group. I have a 75, 25hp evinrude I have been rebuilding, and I have it to running condition, however, it's sneezing at all RPM's. Rich, lean dont seem to affect it. Carb plate is fully closed at idle, opens right between the armature dots. Points clean, adjusted to .20, nice spark. No obvious oil from the upper seal. Carb ultrasonically cleaned, with plugs removed, replaced. Replaced the powerhead base gasket when I replaced the shift lever. I'm getting a little lost now as to where to check next. Also, on the exhaust cover, there is an open, threaded hole not obvious on the schematic. Does this serve a purpose?

 

[racerone]

Fuel filter was mounted there on some 22 cubic inch models.

 

[jimmbo]

Missing at all rpms? Well Fuel and Spark are the Suspects. Fuel Starvation, but it should run fine at lower Rpms. Internal Breaks in any of the Wires in the Ignition system. That Ignition System uses only 1 Coil under the Flywheel, and a Coil next to each cylinder. The wires from the Armature Plate to those coils might have a continuity problem

 

[drkilldrmz]

Missing at all rpms? Well Fuel and Spark are the Suspects. Fuel Starvation, but it should run fine at lower Rpms. Internal Breaks in any of the Wires in the Ignition system. That Ignition System uses only 1 Coil under the Flywheel, and a Coil next to each cylinder. The wires from the Armature Plate to those coils might have a continuity problem

As much as I was hoping not to remove the flywheel again, this makes sense. I have a new sierra points,condenser tune up kit, but I don't fully trust the aftermarket. Off she comes, and I'll post up a video when the rain stops. Thank you for nudging me to do so. Again..

 

[jimmbo]

Maybe a bad Capacitor(condenser)

 

[drkilldrmz]

Maybe a bad Capacitor(condenser)

Preparing for a full day's rain out tomorrow, but I'll replace everything up in there Thursday and hope for the best, or post up a video if not. I'm sure you guys have seen it all..

 

[saltchuckmatt]

Hello group. I have a 75, 25hp evinrude I have been rebuilding, and I have it to running condition, however, it's sneezing at all RPM's. Rich, lean dont seem to affect it. Carb plate is fully closed at idle, opens right between the armature dots. Points clean, adjusted to .20, nice spark. No obvious oil from the upper seal. Carb ultrasonically cleaned, with plugs removed, replaced. Replaced the powerhead base gasket when I replaced the shift lever. I'm getting a little lost now as to where to check next. Also, on the exhaust cover, there is an open, threaded hole not obvious on the schematic. Does this serve a purpose?

This is a little out of my pay grade and I'm not sure if this applies to your older motor. I had an 83, 30 horse and you had to run what I'm assuming is the timing quarter inch past the lines. There was an Evinrude update on that. My motor was doing the same thing, sneezing that is and once I ran that up it was fine. I played with a carb for a long time before I did that. These other guys have more experience than me so they can tell you if that's true to your motor. Pretty sure they're going to say it's not. Hope you find it.