1959 10hp evinrude sportwin idle/rpm/throttle issues

I am working on a 1959 evinrude sportwin and I finished up rebuilding the carb, resealing the lower unit and gear case. I set the low (1-1/2) and high speed needles (3/4) to factory settings and it does start up easily. However the motor dies right before i even throttle it down from the start position(which actually starts more in the run position) to the shift setting to put it in gear (forward or reverse). I have started up the motor in forward gear and it doesn't seem to get up to full speed (rpm). I ran it for 10 min in the tank and when I throttled it down and right before it got to the shift position it died (multiple times). It runs alright with a slight vibration but it doesn't rev up near as far as it should go. I did replace the plugs as well. The pressure tank was all redone with new gas/air lines. Fuel mix is 24:1 with new premium gas. i am looking for assistance on what can be causing this as well ways to fix it. Thoughts and suggestions?

I would say it is running on 1 cylinder.----Check for strong spark ( 1/4" or more gap ) om both leads.

Welcome aboard the forum. Agreed. Running on one cylinder. Have the spark coils, points, and condensers been replaced? These coils, if originals, are cracked. The coating used by Evinrude/Johnson will crack even in the best of storage conditions, then the coils will arc down to the stator plate underneath. Most certainly they have been replaced, or it might not run at all.

timguy said:

Welcome aboard the forum. Agreed. Running on one cylinder. Have the spark coils, points, and condensers been replaced? These coils, if originals, are cracked. The coating used by Evinrude/Johnson will crack even in the best of storage conditions, then the coils will arc down to the stator plate underneath. Most certainly they have been replaced, or it might not run at all.

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I am 100% sure that I didn't check those and most likely the previous owner didn't either. I was told that it ran well when it was last used... Famous words.... I picked up a gap tester today and will check it in the next few days! I will let you guys know what I find. Thanks! I appreciate it!

Quad1994 said:

I am 100% sure that I didn't check those and most likely the previous owner didn't either. I was told that it ran well when it was last used... Famous words.... I picked up a gap tester today and will check it in the next few days! I will let you guys know what I find. Thanks! I appreciate it!

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Checked the spark gap for both boots. Didn't get a spark to jump 1/4 on either. Had spark on both originally when I changed them but definitely not strong spark obviously. Ordered new coils, condensers and points. Points looked pretty worn...

Were the coils cracked?

Having 'done ' a few of these engines and their sisters...I've always found that 3/4 out on the main jet is too much and results in exactly the same situation as you mention, firing then dying immedeatly. I've found that seating both jets, leave the top low speed one alone to start with but take the bottom/main needle out a fraction at a time, If like me most times the needle will be out about 1/4 turn maybe a fraction more/less and she'll run fine and adjust accordingly. Alter the low speed jet at low revs similarly once you've done this. This is only my experience and I'm no where near as qualified as some of the guys on here....

It really is elegantly simple.------The initial settings are 3/4 turn out for high speed ( lower ) needle.----And 1-1/2 for low speed.------That will get the motor running and keep running.-----Then you MUST make the final adjustments with motor running and warmed up on a boat.

That's right, Racer....a barrel doesn't work well because exhaust fumes are concentrated......messing up the mixture......besides that, your tuning with the cowling open....or off completely.

timguy said:

Were the coils cracked?

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Coils were not cracked.

Then they were replaced at one time. Probably gonna end up being the points. When you install points, make sure to put a tiny scosche of grease on the pivot post. Also a drop of oil on the cam follower wick. If the wick is bad, then it should be replaced. If the cam follower wears down because of lack of lube, you may have to reset the points again within the next 10 years or so. I also put a tiny dab of a high quality synthetic grease on the cam.....making sure it dispenses evenly on both of the tabs where the points contact the cam. I consider it a failure if I have to even LOOK at the points within the next 10 years. This is brilliant, bulletproof, and simple engineering. When properly serviced and maintained, you can trust your life with it.....I know, I have.

timguy said:

Then they were replaced at one time. Probably gonna end up being the points. When you install points, make sure to put a tiny scosche of grease on the pivot post. Also a drop of oil on the cam follower wick. If the wick is bad, then it should be replaced. If the cam follower wears down because of lack of lube, you may have to reset the points again within the next 10 years or so. I also put a tiny dab of a high quality synthetic grease on the cam.....making sure it dispenses evenly on both of the tabs where the points contact the cam. I consider it a failure if I have to even LOOK at the points within the next 10 years. This is brilliant, bulletproof, and simple engineering. When properly serviced and maintained, you can trust your life with it.....I know, I have.

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I just wanted to thank you guys for your help. I replaced the ignition system and it runs very well. Now I just need a boat to try it out on! But none the less it tested great in the bucket.