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1975 Evinrude Fisherman 6hp (6504R) Slow Speed Needle Adjustment

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Swarlos

Regular Contributor
I have a '75 Evinrude 6hp. The throttle feels stiff, but it seems to be working. I am only able to start and run the motor if it's on Fast speed according the plastic markers on the throttle. I need to warm the motor up for quite awhile before I am able to shift it into gear because if I bring the throttle down to a low enough level to shift in gear it will usually stall if it isn't good and warm. I wonder if something is off on the throttle or if the setting on the low speed valve is incorrect. What is the correct starting point for the slow speed needle? I have tried gently seating the needle then backing off 1-1/2 turns, but that doesn't seem to correct the issue.
 
Does spark jump a gap of 5/16" on both leads , yes or no ?----Remove the slow speed needle.----Does it have a pointy end , yes or no ?-----Is the thermostat in place and working properly ?----They are often found stuck open.
 
1-1/2 turns is only the beginning point. It needs to be adjusted from there, on a warmed-up motor, preferably on a boat on the lake. The words on the throttle band are usually inaccurate, nevertheless it should run at any actual speed.

Needing to start it at high throttle suggests an ignition problem or a sick motor. Have you checked the compression?
 
I haven't run a spark gap jump test, I have just ordered a tester. I'll remove the needle tomorrow to see what shape it's in. I don't know how to check the thermostat or even where it is... Just checked where the thermostat is on top of the head, but still don't know how to check to see if it's stuck open.

I understand that the factory setting is only a starting point, but I just wanted to be sure where that starting point is. I can run a compression test tomorrow when I check to see if the needle is still in good shape. Can I remove the needle and thread it through without removing the nut holding the packing/washer in?
 
Swarlos said:
I haven't run a spark gap jump test, I have just ordered a tester. I'll remove the needle tomorrow to see what shape it's in. I don't know how to check the thermostat or even where it is... Just checked where the thermostat is on top of the head, but still don't know how to check to see if it's stuck open.

I understand that the factory setting is only a starting point, but I just wanted to be sure where that starting point is. I can run a compression test tomorrow when I check to see if the needle is still in good shape. Can I remove the needle and thread it through without removing the nut holding the packing/washer in?
Click to expand...

Good question. Removing the needle carries with it the danger of the packing material disintegrating and pieces getting down into the hole. Best advice from me is loosen the nut just enough to take the pressure off the packings. More truthfully, I wouldn't even be taking it out without better indication to do so. I realize racer's thinking is that the tip is broken off---certainly good reason to look.
 
Swarlos said:
I haven't run a spark gap jump test, I have just ordered a tester. I'll remove the needle tomorrow to see what shape it's in. I don't know how to check the thermostat or even where it is... Just checked where the thermostat is on top of the head, but still don't know how to check to see if it's stuck open.

I understand that the factory setting is only a starting point, but I just wanted to be sure where that starting point is. I can run a compression test tomorrow when I check to see if the needle is still in good shape. Can I remove the needle and thread it through without removing the nut holding the packing/washer in?
Click to expand...

It'll be obvious if it is stuck open. The round" flap" on the top will be raised above the mounting flange so that water will pass through.
To test put in warm water and slowly heat while measuring the water temperature. It should just start to open at 143F

I had mine stick open but I only discovered it because I decided to take a look at it. It did not affect the running or starting.

I'd do as fdrgator suggests when removing the needle
What can happen is that the pointed tip gets broken off and stuck in the orifice if screwed in to tightly
 
Picture of thermostat from the parts catalog on this site
5005440.jpg
 
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