1973 evinrude 50 hp

fishdady

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Jun 27, 2012
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I have a 73 rude 59 hp. Model 50373r. I have cleaned and rebuilt the carbs, but, I can't get it to idle. Seems to be dumping gas untill it floods out. I have tried everything, checked the float drop twice, adjusted numerous times. Lower carb is especially bad. Beginning to wonder if these carbs are right. Float bowl has 313355 number on it. Research shows this was on a 25 horse. It sat for 4 years before I got it. Any suggestions would be appreciated! Thanks
 

Joe Reeves

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Feb 24, 2002
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The floats should be set as follows:********************
(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.
********************************

1 -Make sure that "all" of the jets are absolutely clean!
2 - The linkage between the carburetors should be adjusted so that, with the cam NOT touching the throttle roller,... the throttle butterflies open and close at the same time..... You do not want one closed and one slightly open.
3 - The throttle butterflies should just start to open when the scribe mark on the metal cam is dead center with the throttle roller.
 

fishdady

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Jun 27, 2012
Messages
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Will look at everything, again. I've gone through all this, but, will go through it again. Didn't know I would get the master right off the bat! Thanks, Joe. I should mention the idle control valve was bent, replaced it and getting the "bearing" out was more fun then I have had in a long time (Lower carb)
 

Joe Reeves

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Feb 24, 2002
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Idle Control Valve?.... I don't recognize terminology. What are you speaking of?
 

Joe Reeves

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Feb 24, 2002
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*Low speed valve, sorry!

*Slow Speed Needle Valve

This "bearing" you mention... Would that be the threaded "Aluminum Barrel" that the S/S needle valve screws into? If so... that's easily removed by removing all the packing washers, then screw the S/S needle valve into it, then just yanking it out of there.
 

fishdady

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Jun 27, 2012
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Bearing is actually a nylon bushing that goes on the low speed needle valve to guide into the center. That's what the book and parts schematic calls it. Thanks for your help.
 

Joe Reeves

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Feb 24, 2002
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Bearing is actually a nylon bushing that goes on the low speed needle valve to guide into the center. That's what the book and parts schematic calls it. Thanks for your help.

Oh, okay... yeah, that would be that very small bushing/bearing that the front of the needle valve rides upon, designed to keep the needle valve from being damaged by engine vibration. Agreed... that thing can be a real headache to remove.

I found that by using a small tap, I think it was a size 4x40 (not sure) and hand screwing it into that bushing, the threads of the tap grabbed the insides of the bushing but didn't go thru to the aluminum. Having a small vice grip attached to the tap would let one yank it out of there.

Curious.... what approach did you come up with to remove it?
 

fishdady

Petty Officer 3rd Class
Joined
Jun 27, 2012
Messages
78
Ready for this; took a paper clip, bent a hook in it, cut the bend very short, like a small hook, ran it in the hole and caught the lip. Top carb came out fairly easy, bottom carb was a different story. Top carb "Bearing came out fairly in tac, bottom carb it was crushed, assume by the bent valve. Amazing the things you can find in some of these older engines!
 
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