1973 evinrude 25 hp ignition problems

[evvy]

I recently acquired a '73 evinrude 25 with no spark on one cylinder. I switched the wires that go to the external coils and the spark followed the black wire marked number one, so both of the outside coils are good. After that I pulled the recoil and flywheel, I properly installed an ignition tune up kit. While it was apart I cleaned everything. When I put it back together, same problem. I noticed the flywheel had one magnet, and I thought about it and seems to me it should be two, seeing as how it has one driver coil and needs to fire twice per revolution.(feel free to correct me if that is wrong) I would like to know some more info on this, and any advice is appreciated. I am trying to be cost effective as well, so I don't want to get a flywheel if it may be a pinched wire or something stupid like that. Thank you

 

[HighTrim]

Re: 1973 evinrude 25 hp ignition problems

Have you tested the points on the dead cylinder? CLEAN? Run a continuity test from the points to the plug lead to see if there are any issues.

 

[evvy]

Re: 1973 evinrude 25 hp ignition problems

Thank you HighTrim, I will try that after next week when I go back in after Christmas break with family. I was just wondering if you knew if the single magnet flywheel was correct? That would be a relief and take a little load off my mind. Thanks again.

 

[HighTrim]

Re: 1973 evinrude 25 hp ignition problems

Yes flywheel is fine. Be sure the magnet is ok, should grab a screwdriver from a few inches away.

Likely an issue with the coil/wire/connection.

Test continuity across the points when they are closed. If none, dress, regap, clean with acetone and re check.

If that checks out, check continuity from the points to the plug boot spring. If no continuity, remove the boot and spring and check to see if continuity is getting to the end of the wire. If so, there was an issue with the spring making contact with the wire. If continuity there, faulty plug.

 

[evvy]

Re: 1973 evinrude 25 hp ignition problems

I know that both external coils, plug wires, plug boots and plugs are fine because when I switched the coil wire connections, The spark moved with the number 1 wire. So both systems past that little black connector have sparked good. I probably missed something small then, like a pinched wire or some oil on a set of points then. Thanks

 

[evvy]

Re: 1973 evinrude 25 hp ignition problems

Sorry it took so long to get back to you, I got really busy. I took the flywheel off again and tested everything and it all checked out, so I swapped the points and condensers from side to side. The spark stayed with cylinder number 1. I found an old Evinrude shop manual with detailed diagrams of the ignition system, and it shows two magnets on the flywheel. Part of the description was "Magnet one is 180 degrees from magnet two, and both should have strong pull on a screwdriver or bolt from a couple inches away". So I'm just going to try a different flywheel. I found a couple reasonably priced under forty bucks with shipping.

 

[evvy]

Re: 1973 evinrude 25 hp ignition problems

got the newish used flywheel and it had a magnet on each side like it should. Good spark on both cylinders after a 5 minute flywheel swap, but now somebody in the shop got sticky fingers or wanted to **** me off and took the low speed mixture screw from my parts bin. Where do I find another one? I also need to sell the good older style flywheel that was on the engine.

 

[AlTn]

Re: 1973 evinrude 25 hp ignition problems

dealer may have them or marineengine.com

 

[evvy]

Re: 1973 evinrude 25 hp ignition problems

I found the adjustment screw when a friend was working on another engine next to me and says "I can't figure out where this big brass needle thing goes". he grabbed it off the counter a couple days ago because he thought it was off his weed eater carb. He isn't too bright sometimes, but everybody has their moments. I threaded it in and set it to the initial setting. Stuffed the engine in a barrel, it poped and spit for about ten pulls. I found out I had the point-to-external coil connectors flip floped, so I put them back to normal(no big deal, about one minute thinking and two minutes fixing it) Then she fired up on the first pull and ran perfect, no misfires or sluggishness. Idles low and smooth. Thanks for the help.

 

[kfa4303]

Re: 1973 evinrude 25 hp ignition problems

sweet! congrats!!!! Happy Boating!

 

[AlTn]

Re: 1973 evinrude 25 hp ignition problems

Thanks for the education < to me at least > on the 2 magnet flywheel!

 

[69 Alumacraft]

Re: 1973 evinrude 25 hp ignition problems

Thanks for the education < to me at least > on the 2 magnet flywheel!

I need a 1 magnet flywheel for my 25 I want to convert it to old school ignition are you willing to part with it? When I do this I will have new coils I will no longer need that will fit your motor, mine is a 76 25hp rude . Can you PM me?

 

[kfa4303]

Re: 1973 evinrude 25 hp ignition problems

Check ebay for flywheels too. You can usually get them fairly cheap.

 

[weh8625]

Re: 1973 evinrude 25 hp ignition problems

Check ebay for flywheels too. You can usually get them fairly cheap.

I have the same '73 Evinrude I'm working on for a friend.
I have no spark on either plug, and I just pulled off the flywheeel last night.
Do any of you have a picture of how it's supposed to look under the flywheel?
This is the first time I've seen one with external coils.
Also, is there a good way to test the coils, condensers, and points to see where the problem is?

Thanks.

 

[kfa4303]

Re: 1973 evinrude 25 hp ignition problems

HI weh8625. I would start your own thread for this topic. Unfortunately, I'm not very well versed in these transitional ignitions, but here's a link that can explain the basics. Hope it serves.

http://www.sschapterpsa.com/ramblings/johnson_9.9_magneto.htm