May 3, 2019 at 3:43 pm #174776
HV pin to either low primary wires (black or green) should show 4-7 kilo ohms if not coil is open inside it could be open anywhere and arc internally during higher RPMS
in theory the faster the magnet fly by the coils the more ” kick” is generated when the fields build up and collapse later this can boost the HV enough for internal arcing
when you solve the problem and in conclusion if a new coil solves your problem you should do some coil surgery . the arcing point should show a blackening surface somewhere inside the coil . The HV pin may just… pull out
btw…. what does your “good coil” give results wise…May 3, 2019 at 5:34 pm #174783
i ordered a new coil was 24.99 and at this point i dont want to mess with the good firing cylinder lol if it not broke dont fix it or mess with it is what my father told me long time ago and i’m sticking to that..coil has to be bad i get nothing on the out put side of coil not even continuity.May 3, 2019 at 5:43 pm #174784
interesting i was looking at coil and there is a very small line of the sealer or opoxy from the back side that ran down the coil it is very clear didnt see that till i looked at it real close. how do i get inside the coil to look at stuff.May 3, 2019 at 7:06 pm #174793
try a hammer to crack the case ….
burnt wires , inner varnish coating will be apparent where arcing took place
glad to see you are making headway …..I also have a 59 5.5hp Golden Jubile ready to try out in a few weeks
as to the measurements on the other coil you just need to pull the boot and measure in place… no need to dismantle 🙂
from the boot spring clip to the engine body (any shiny non painted surface will do ) should see 4-7 kohmsMay 3, 2019 at 8:38 pm #174796
i will go check little later and see..i will wait to crack open the coil till i get the new one and it running how it should..i love my golden gubilee these motors are so smooth and quit…not to mention it pushes my 12 foot boat with me and gear an extra 200 pounds worth lol at 13 mph not bad for a little 5.5hp vintage motor
US Member - 2 Years
Topics: 32May 3, 2019 at 9:52 pm #174798
Those digital meters can be confusing and misleading, especially if you don’t have them set correctly. When you say “no reading”, I am assuming you mean infinite ohms or an open circuit. I am assuming that the green wire is the coil primary lead and the black wire is the coil ground, common to the primary and secondary leads. The proper way to test the secondary circuit is to touch one lead to the coil ground lead, the other lead to the plug terminal, this should show several thousand ohms. Touching one lead to the coil ground lead, the other lead to the coil primary should show about 1 ohm. Needless to say, your meter must be set properly or you will misinterpret the results. You may want to try testing the other coil first and compare the results before buying a new coil. Keep in mind, that even a coil that reads correctly on an ohm meter may be defective, especially if the secondary has an external leak/crack allowing arcing to ground.May 3, 2019 at 11:28 pm #174800
meter reads zero no ohms i did the same on other one and that did read .8 then nothing kinda weird.i tried it in all modes and same out come.so dont know what is right but i ordered a new coil..only thing else it could be is fualty piont for some reason but they look great and are clean.May 4, 2019 at 12:11 am #174801
1- touching your probes together will give you your 0 ohms referrence (max conductivity since the probes are touching themselves. IF using a needle meter touch the probes and …adjust the needle to 0 ohms to establish a referrence of 0 ohms on the scale being used .Always reset the needle to 0 when changing to a diff. scale.
Make certain the meter’s inside battery is fresh……..(they all have a battery inside) !!!!
2- that said probing the green and black will give you your primary winding resistance 1-3 ohms max not much more (if using a needle meter use 100 ohms scale or lowest possible scale above the expected 3 ohms reading
3- that said ….. black to HV pin probing gives you the secondary winding at 4-7 kohms … if using a needle meter set the scale to 10 kohms !!
if your digital meter shows nothing (no value) similar to when the probes did not touch themselves before starting step 1 above …. you have infinity … open …. infinite resistance (air) which is an open secondary winding
US Member - 2 Years
Topics: 32May 5, 2019 at 7:51 am #174833
I am assuming you were checking the primary circuit during you restest, correct? .8ohms seems correct, zero ohms means the primary is completely shorted….That being said, those digital meters are very hard to read, and not all that accurate when reading super low resistance readings (below one ohm). The readings seem to jump around and add to confusion. I admit to being “old school”, and love my simple Stevens AT 101 analog meter….Like anything else, I’m sure there are some digital meters that do a great job in the low ohm range, but the jumpy readings sure can be confusing….
OK, so you have ordered a new coil. If the new coil doesn’t solve the problem, then I would swap the points to see if the problem swaps cylinders….If not, I would swap the condensers. Bad condesners are often overlooked, and they do deteriorate with age. And, just because they are new, doesn’t mean they are good. I am trying to remember if you replaced the points and condensers, am assuming you did…If so, did you use an OMC ignition kit?May 10, 2019 at 2:54 pm #175045
ok so got new coil on and went through points again…still losing spark at about half throttle but was messing around with it because it weird that it doing this..so at half throttle i lose spark but when i push down a lil bit on the mag plate where the piece sticks out to move the throttle the spark comes back and is fine..i am lost now any one have this problem…i did put very lil grease on the bottom of mag plate when i resembled it where it makes contact with mounting plate for it and the inside of mag plate should i have not done that.
US Member - 1 Year
Topics: 43May 10, 2019 at 4:44 pm #175046
You did right in lightly greasing the mag plate. Low voltage does not cross that junction, only high (spark) voltage which has no problem getting past the thin smear of grease.May 10, 2019 at 5:04 pm #175047
try adding a piece of wire linking mag plate surface to engine surface this will ensure electrical conductivity between sparkplug bodies and the ultimate return path to the high voltage coil winding (the secondaty winding)
when you push down on the mag plate you are probably closing the path
mesh shielding from a piece of TV coax cable makes a nice flexible conductor
just for a test … with that new coil
you should now read a good 4-7 kohms on the secondary at the plug boot when measured to the engine main body
if not find out why !! press down on the mag plate to see if 4-7kohms suddenly appears
both secondaries should have solid 4-7 kohms
- This reply was modified 3 months, 1 week ago by crosbyman.
US Member - 1 Year
Topics: 43May 10, 2019 at 6:29 pm #175051
Pressing down on the mag plate changes the breaker point gap and clearance between the coils and magnets. This could be significant if it is worn really sloppy. However, they all have some wiggle.May 10, 2019 at 7:25 pm #175053
well if the ground wire does not help we will know it is more mechanical than electrical
hoping to see ohms readings and wiggling impact on measurements.
when we find cure for this oldy I am certain we will be amazed
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