Can not get this 18 running right.

[wiscoboater]

Hello gents,
I’m hoping some of you can help me out here. I’m tearing my hair out with this 59 Evinrude 18. Here’s where I’m at. This motor sat for a lot of years before my purchase of it. I did the usual, new plugs, rebuilt carb, repaired the pull starter, checked both cylinders for spark (present on both). I removed the cover on the flywheel and looked at the coils, both are intact but one is blue, the other black so not a matched pair, but functioning. Shot some electric cleaner on both sets of points through the inspection hole in the flywheel. Set the high speed needle at 3/4 turn out, low speed at 1 1/2 turns out. The motor starts and runs poorly….fiddle with the needles for an hour and a half…still runs badly. I can get it to idle but not real low, about the start position on the tiller and lined up with the embossed line on the brass plate that the roller rides on that opens the throttle butterfly. When I try to rev it up a bit it has no misses or sneezes, and when reved up turning the high speed needle in does increase RPM. Heres where it gets weird. If I throttle it back down, it stays revved up and starts to miss a bit…sort of like it’s running out of gas. Looking at the glass fuel bowl when this is happening it is almost empty. It gets stuck at this revved up state and will not come back to idle so I have to hit the kill button to keep it from over revving. At that time the fuel bowl is almost dry. Hit the starter a few seconds later and it’s back ideling, but only at the start position on the tiller. I have all new fuel and air lines on the motor, nothing is leaking. I just rebuilt the fuel connector with new BRP Orings and that’s not leaking. The pressure tank seems to pump up ok. What am I missing here? I just got an electric start set up for this motor and I want to use it on a wood boat project I’m working on, but I just can not seem to figure out why it is acting like it does. One last thing, after running it and fiddling with the needles for almost two hours I checked the new J6C plugs. They were slightly wet, not bad really and black with just a hint of brown at the tips. Don’t know if that helps, but thought I would throw that in. Any help appreciated.
Thank you. wiscoboater

[phil-b]

Basics:

Leaning out a too rich mix will speed up the engine.
Leaning out too much will result in a "sneeze" or miss.

You said it had good spark– you didn’t say how you tested.
To have good spark under compression the spark has to be able to jump a 1/4 inch gap in open air.

[frankr]

OK, the won’t slow down thing is called run-away. That is caused by revving it up without being under a load. So, I can only conclude you are running it out of the water or in a bucket or something. So…the first thing you need to do is get it on a boat, on the lake, in gear, then adjust it. You can’t adjust it under whatever circumstances you are doing now.

Second thing, the glass bowl will always run nearly empty. Don’t try to explain it, just accept it. Something about capillary action.

The motor very well might be just fine once you run it where it was designed to run. If not, check back.

[wiscoboater]

I used an open air spark tester. It has a plug end on one end and an alligator clip on the other. it can be adjusted by screwing it in or out to change the gap between the two points. I checked it at 1/8 inch and had blue spark. I will try it at 1/4 see how it looks. That and I’ll borrow a boat from a friend and try it under load. I just won’t wander far from the dock.

Thank you to both of you, Wiscoboater

P.S.
I was running it in a 55 gal. drum with a fan blowing away the exhaust smoke. I did not try it in gear, only in neutral. Thank you for your patience with us rookies Frank. I’m learning a little every day about these things. The help from this site is truly better then any manual printed.

[chris-p]

Is the linkage catching or sticking when you throttle down? Watch it at the carb, may be old grease and dirt that needs cleaning and new lube.

If it has been sitting, I would pull the flywheel and polish the points, reset at 020 and then clean by running a business card or paper stock dipped in acetone through them. They are likely glazed over.

[Mumbles]

It sounds like you may have a leaking seal at the top of the crankshaft. The symptoms you describe could be caused by air getting in thru a worn seal which is a common issue with these motors.

To check for a bad seal, I pour a bit of fuel or oil on the seal and turn the motor over by hand. Any bubbles coming up lets you know it’s time for repairs. While you have the mag plate off, you might also want to give the points a polish to remove any buildup from sitting for so long.

Here’s a short vid showing how I do it.

https://www.youtube.com/watch?v=cXt6fV6 … load_owner

[wiscoboater]

Should I run a folded piece of 600 grit wet/dry sand paper through the points before the acetone soaked business card?

[frankr]

quote wiscoboater:

I used an open air spark tester. It has a plug end on one end and an alligator clip on the other. it can be adjusted by screwing it in or out to change the gap between the two points. I checked it at 1/8 inch and had blue spark. I will try it at 1/4 see how it looks. That and I’ll borrow a boat from a friend and try it under load. I just won’t wander far from the dock.

Thank you to both of you, Wiscoboater

P.S.
I was running it in a 55 gal. drum with a fan blowing away the exhaust smoke. I did not try it in gear, only in neutral. Thank you for your patience with us rookies Frank. I’m learning a little every day about these things. The help from this site is truly better then any manual printed.

Well ok, there is your answer. Revving it up in neutral. That is causing your runaway. Also why you can’t adjust it. Let us know how it works out on the boat.

[wiscoboater]

Will do, Thank you Frank and everyone else.

[fleetwin]

Are you sure the carb butterfly is closing, not binding? Maybe the linkage is binding/throttle shaft gummed up causing the throttle to hang open when you decelerate causing the runaway/sneezing when decelerated.
Otherwise, do what Frank says! Best to get this thing on a boat in the water before getting too deep for no reason.

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