Canada Member - 2 Years
Topics: 416May 21, 2019 at 12:06 pm #175660
Your spark returns to the mag plate thru the top of the brass retainer ring which is also a support bearing for the plate and also thru the center bearing which the plate rotates on. These areas must be free of any corrosion or buildup of any kind which can impede the electrical flow. Lightly sanding the inside of the plates bearing surface and other contact surfaces will help to ensure a good electron flow. Don’t bend or deform the brass plate.
To determine if the plate is too loose, try wiggling one edge of it up and down while holding the opposite edge still. A good fitting plate will hardly move at all while a loose one will flop around quite noticeably.
If it isn’t poor grounding causing the spark issue, I’d then suspect internal breaks or shorts in the plug wires or poor connections on the ends of them.
- This reply was modified 3 weeks, 6 days ago by Mumbles.
US Member - 2 Years
Topics: 31May 21, 2019 at 1:02 pm #175681
I thought he had already tried grounding the mag plate, perhaps I misread the post….Nonetheless, your theory of a loose/misrouted plug lead makes sense….
Canada Member - 1 Year
Topics: 158May 21, 2019 at 5:57 pm #175714
if it was me….
I would really clean up the whole oily looking mess of an engine……… certainly any part carrying electrical currents ..as suggested redo all connections from coil up to the boots clips… if need be install new boots with metallic wire crimped & folded back under the clips as suggested by mumbles
shine up.. polish all contact points and/or surfaces (retainer ring…… mag support plate coil grounds ( scrape all connection points and use star.. lock washers to bite into mating surfaces ) reinspect the mag plate plug wire routing
swap that lower coil/condenser/point kit to the top cyl position …we know it is good and never causes a problem
remeasure the coil secondaries for 4-7kohms from the boots to frame…. wiggle everything while measuring … see if it cuts out
reassemble the whole thing dry … no greases ..oil as a test … and keep that mag plate grounded as insurance
realign the coil edges on the mag plate
find a way to run that engine in the dark…3 a.m. if need be ………… look for arcing anywhere at high rpm when it fails
if all else fails make a nice trolling motor out of it !
..patience brings joy
June 3, 2019 at 3:31 pm #176572
- This reply was modified 3 weeks, 5 days ago by crosbyman.
ok i got back on the motor…so i took it all apart cleaned up all the oil there was a bit packed up under the mag plate hold down the big one…put back together and now it run even worse than it did now the bottom has no spark at idle…but i took it apart again getting really good at it only takes me 5 min to tear aprt lol…and in pic you can see the bushing does have a small gap could this be my whole problem..i’m thinking of puting some really small thin pieces of copper in between it to make it a lil tighter do you think it will work or ruin it more…other than the litlle gap ii’m loss of words why it wont work and just about ready to throw it out…June 3, 2019 at 5:35 pm #176582
so i put it back together and got spark on the bottom cylinder like i always did…still nothing on the top it is dead now but if i hook up a ground wire to spark plug end it lights up my tester but plug still doesnt have spark.odd any thing else i should look at..think i’m going to return the coil for a new one say it is fualty since now the screw terminal where the plug wire goes in came out of the coil..just can’t win
US Member - 1 Year
Topics: 43June 3, 2019 at 7:37 pm #176585
That gap in your picture means nothing at all. The mag plate centers on the crankcase neck, not on the mounting ring.June 4, 2019 at 11:12 am #176600
ok good to know…so i should have a good ground then if the bottom cylinder has spark…i’m going to buy some new plugs try that…and going to see if local parts store has diff spark plug ends the ones that you bend wire around wire and clamp on insteae of the old spring looking ones that you just push into wire..i cant figure out why my tester lights up if you ground it out but plug will not spark unless it is bad for some reason….can i just glue the little screw terminal back into coil where the plug wire goes or is the new coil junk.June 4, 2019 at 1:07 pm #176607
so i put old coil back in..put the clamp on style plug end on new wire and same thing…i get good spark in certain throttle positions then i get weak spark where the spark tester will light up but the plug wont then i get no spark at all…been through everything now and nothing seems to help..hoping some one with the same problem comes along and see this post becouse i checked everything and nothing seems to help
US Member - 2 Years
Topics: 12June 4, 2019 at 3:11 pm #176613
What kind of spark tester are you using??
I use one like this:
And open it to a quarter inch (compensating for the fact that it’s harder to make a spark under compression) and I’m not satisfied unless I get a blue spark and a good “snap” sound.
After sanding the points, I always clean them by running clean paper dipped in acetone thru them.
June 4, 2019 at 6:10 pm #176627
- This reply was modified 1 week, 6 days ago by phil.
i have a inline spark checker that lights up if there is spark…i sanded and cleaned points a few times now..there is plenty of meat left on them too almost look new very little wear…and i switched everything to the bottom cy;inder that works and i get spark except for the points…i dont think it is a ground issue becuose the bottom cylinder works fine.June 4, 2019 at 6:12 pm #176628
i might hook a drill to flywheel to spin it over at night see if i see any arcing going on.
US Member - 1 Year
Topics: 68June 5, 2019 at 5:46 pm #176687
Since you swapped coils, condensers, and points without much change I would suspect the spark plug wire to plug terminal connection. The stab-in terminal at the plug end may not have a good connection with the wire copper core. Some folks strip 3/16 or so of insulation from the core and fur the copper strands to increase the chance the end may contact the terminal. Also stab in again and confirm by feel that you are indeed through the copper core.June 6, 2019 at 7:16 pm #176749
there is brand new wire just put on and just switched terminal end to the clamp on style…dont get it if bottom cylinder has spark then there is good ground…only thing i didnt change is the points i might order a set and see also have another new coil coming but dont think that is the problem.
You must be logged in to reply to this topic.