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1973 Evinrude 25hp, Odd black box on motor

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Sirrobbythe5th

Contributing Member
Hello I have a 1973 Evinrude 25hp and it has this small black box by the fuel pump that has electrical cables running into it. Ive searched everywhere and I can't figure out what the hell it is any ideas??.. and before you say it ....its not a powerpack

ALSO,, after tons of trouble shooting and money... I have finally narrowed down that my bottom cylinder is missing...I took the top spark plug lead off while trolling, and it died, put the top back on and took the bottom off...and wouldn't you know it. It ran great. Minus the lack of power....
any ideas on where to start on fixing this??
My compression is good...118 on both cylinders.
 
There is no black box on a 1973 25hp. Where do the wires lead to? Who knows what somebody has added?? How about a picture?
 
Heh, I was wondering if that was what he was talking about. But then I said to myself, nah that hardly is a "black box". Well, I guess it is "black".
 
For the black box: Its connected to the battery and the starter...Im assuming its a solenoid, it a black square cover about 1" x 1"
As for the motor.....I just set my points today at .020, using the crank shaft I set the points when the hit the set mark.... I checked my condenser and its good ( set the multimeter to ohm.. held it for a second, then switched it to dc and watched it slowly go down when connected) NOW heres the kicker.... The points for the bottom cylinder are not perfectly lined up they are offset a tiny bit and the faces are flat... not rounded like this... )(
Also there is only one coil under my flywheel
Then there are two by the spark plugs one for each plug with a lead on it
Im running out of options here............
 
I will switch the engine coils and see if thats it. Would the points not lined up cause that much trouble on the second cylinder ??
How would the lower crankshaft seal be an issue in this matter?
and Im running a brand new tank, new oil quicksilver tc-w3 at 50:1 ratio, new hose for the tank, an inline filter on the hose...and I just rebuilt the entire pump
 
ok. got it . so the set mark on the cam doesn't really matter? those marks on the armature plate and flywheel are more important? I take it any timing light will work?
 
Do you adjust the points when the the throttle is Wide open??, so throttle wide open and adjusting them so they are at a .022in gap when the mark on the flywheel is in-between the two marks on the armature plate??
 
ok update here, I switched the coils by the spark plugs.. and same thing,,, I put the top on bottom and the bottom on top and switched all the wires. The top one still runs ok and the bottom is running like ****. The only other thing i can thing of is points and confessors and timing ? still curious about were there throttle needs to be at to set the timing.
 
It does not matter where the throttle is when you set the points !!!!-----You are timing the points to open at the correct time relative to the rotating magnets.-----That is why this simple set-up is caled a " magneto "
 
We'll excuse me being naive here, but I have set the points and gap in relation to the set mark on the "cam". But they do not open in relation to the marks on the flywheel and armature plate . The points on the top cylinder open when they should "being they open at the set mark and the marks on the flywheel. Buttt the second cylinder does not open in relation to the marks on the flywheel and armature plate. Even though they open when the set mark on the cam hits them. Am I missing something here?. But also like I said, I switched the coils and same problem .
 
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