'58 FD-12 Super Lean

[roger56]

Re: '58 FD-12 Super Lean

I have a 59 Johnson 15HP some of the same issuses, I though i had good spark on both cylinders. Motor will run on one cylinder. I ended up Replacing the plug wires with new ones to correct my Problem. I also cleaned carb Replaced coils condensers points. All along it was one bad plug wire. Some one told me while motor is at idle pull one of the plug wires off does motor keep running. If it does put plug wire back on. Pull the other off does it keep rumnning?. I had one wire that was not suppling enough spark fire the plug. Hope this helps

 

[nwcove]

Re: '58 FD-12 Super Lean

only reason i asked asked was that i have a smaller motor , same vintage, it idled well, ran at wot well, but it kicked like a horse in the middle. i tightened up the mag plate ( joe reeves method) , and the motor now runs perfect.

 

[Big Jay]

Re: '58 FD-12 Super Lean

I have a 59 Johnson 15HP some of the same issuses, I though i had good spark on both cylinders. Motor will run on one cylinder. I ended up Replacing the plug wires with new ones to correct my Problem. I also cleaned carb Replaced coils condensers points. All along it was one bad plug wire. Some one told me while motor is at idle pull one of the plug wires off does motor keep running. If it does put plug wire back on. Pull the other off does it keep rumnning?. I had one wire that was not suppling enough spark fire the plug. Hope this helps

I pulled the leads one at a time figuring it couldn't hurt, but with one lead off it ran like crap, and gave me a good shock too lol. Thanks for the input though, I've managed to get spark jumping bright blue just over a 1/4 inch on both leads on my spark tester since the mag plate rebuild... However the leads have not been changed since I got it, I did snip a 1/2 inch off each end therefor giving myself fresh copper connections at both ends.

 

[Big Jay]

Re: '58 FD-12 Super Lean

only reason i asked asked was that i have a smaller motor , same vintage, it idled well, ran at wot well, but it kicked like a horse in the middle. i tightened up the mag plate ( joe reeves method) , and the motor now runs perfect.

I'll have to remember that, too much play and wobble at certain rpm threw it off I guess...

I have a sister in Windsor BTW.... you live in a beautiful end of our country

 

[82rude]

Re: '58 FD-12 Super Lean

if you go to this site and look at the diagram you will see there are no washers for the coils atall certianly not 2 .http://www.marineengine.com/parts/v...ntage-evinrude-johnson/377514/37751400001.htm page 4 ,you can zoom in also.top left .

 

[jbjennings]

Re: '58 FD-12 Super Lean

Some pesky problems on the old ones that I've run into and thank goodness, read about....

Sintered fuel filter stopped up/partially stopped up
Throttle cam roller shaft bent, causing synchronization to be off.
Air leak at welch plug on top of carb.
plug wires arcing to goofy locations
weak condensers/inconsistent spark
Throttle shaft on carb leaking air
Bad lower crank seal

If you haven't checked for carb/timing synchronization, you should. The throttle plate in the carb should just barely start to open as the cam roller passes the 2 marks on the throttle cam, and be fully open at full throttle.
I'd also triple check for good consistent spark on that bottom cylinder.
I hope you figure it out,
JBJ

 

[Big Jay]

Re: '58 FD-12 Super Lean

Hey 82rude... I figured there was no way those washers were stock, but they don't seem to be hurting anything. I suppose I should try the motor without them and I likely will in the spring.
JBJ, I have often wondered if there was a way to test that fuel filter but never looked it up. I suppose a new one would simply eliminate any possibility though. I also wonder if the roller linkage is bent too, it doesn't line up at all the way it's supposed to. On my model there is just 1 line on the cam but it's supposed to line up the same I think, but would it run as good as it does if it were as far out of align as I think it is??
I also try to consider the ramifications on the butterfly valve on the throttle, if it doesn't quite open now... how bad will it be if I bend the linkage to restore timing on the idle?

Thanks for the suggestions, it helps me to think outside my narrow box of experience.

 

[jbjennings]

Re: '58 FD-12 Super Lean

I would take the filter out and see if that has an effect. If so, just put an inline filter in the main fuel hose and problem solved.
As far as the cam roller shaft, set the throttle to where the roller and timing mark should touch, and either adjust the cam (2 screws on underside of armature plate) or bend the roller shaft to where it barely touches. If the roller barely touches, and the plate is fully opened when you reach full throttle, it should be right.
Later,
JBJ

 

[Big Jay]

Re: '58 FD-12 Super Lean

I would take the filter out and see if that has an effect. If so, just put an inline filter in the main fuel hose and problem solved.
As far as the cam roller shaft, set the throttle to where the roller and timing mark should touch, and either adjust the cam (2 screws on underside of armature plate) or bend the roller shaft to where it barely touches. If the roller barely touches, and the plate is fully opened when you reach full throttle, it should be right.
Later,
JBJ

Thanks again for the response,

I''l maybe try those 2 ideas out on Sunday or Monday and let you know what happens

 

[jbjennings]

Re: '58 FD-12 Super Lean

One last thing---check the gear mesh on the tiller handle and riser gear to see that they haven't jumped a tooth. That can cause strange symptoms as well, as timing will be off.
JBJ

 

[Big Jay]

Re: '58 FD-12 Super Lean

Huh.... never thought of that, thank you very much. As soon as it's light outside I will check it out

 

[Big Jay]

Re: '58 FD-12 Super Lean

UPDATE:

After replacing the ignition complete except the coils (I removed those washers under the coils and was able to get a much better spark) and including spark plug lines, installing new O-rings in the fuel connecter, a new carb kit and bending the roller cam arm to adjust the sync...

My engine is running as close to new as I could have hoped for !!

Thanks for your help and advice!