coil issue

[palumbo]

Hi I have a 1976 70 horse Johnson outboard 70EL76D. I had an issue with a bad coil that I have replaced. after replacing the coil the boat ran good for 20 minutes and that coil had gone bad again. I replaced the power pack and installed another coil. my question is, what would be making a coil go bad on one cylinder after everything has been checked Out. could possibly be a bad part straight from CDI or could it be another issue on my motor but I haven't looked into yet. I have installed a new coil for the second time just wondering if anybody has ideas before I kill New coil again. I have installed a new power pack and another coil just to see if the power pack was causing it. I haven't had it out on the water to see if new coil will keep firing.

 

[gm280]

:welcome: aboard palumbo. Nice to have you join us...

If you are replacing the burnt coils with OEM coils, then I was suggest you swap the burn coil out with the one that wasn't fried and put the new one in its place to see what happens. For any electrical part to fry, it has to be carrying more current then it was designed for. So make certainly every wire, and component is the absolute proper one for that engine... JMHO!

 

[schematic]

not likely a coil problem. Try swapping coils as mentioned. Most likely a bad cdi pack

 

[palumbo]

so still having the same issue with missing on number 2 coil, new power pack and new coil still creating issue at idle with no spark

 

[palumbo]

So took the boat out for a run seem to be missing on number two cylinder at idle after it warmed up seem to start running just fine. new coil and new power pack. does anybody have any ideas to point me in the right direction. sometimes I have very low spark sometimes no spark sometimes fires just fine, this problem seems to be only on my number 2 coil or number 2 cylinder. did a run for about 40 minutes at three quarter throttle. turn the motor off and ran my kicker for about 2 hours started up main motor again will not fire until I picked up the idle and let it rev for a sec or 2. ran great for another 40 minutes back to the dock. weird issue I got. so interment hard to diagnose. it's fishing time up in the Pacific Northwest bad time to be dealing with my motor issues

 

[racerone]

The electronic components on these engines are very good and reliable.----Answer this question.-----Will spark jump a gap of 7/16" or more on the 3 leads, yes or no ?

 

[palumbo]

Don't know, I do not have that type of a tool. I will go buy one and let you know. all I have is a spark plug light tester. I will post my findings once I find out. thank you

 

[racerone]

You could make a tool with a piece of plywood , some wire and stapler.----Just need to establish a gap between wires to do an ignition output test !

 

[AlTn]

make certain that new coil from cdi is properly grounded...up to and including wire brushing of the mounting bolt, sanding or filing down to shiny aluminum on the block at the mounting point, possibly cleaning the mounting threads with a tap

 

[palumbo]

Ok so found the spark tool at work. I have cleaned the contact points on block very good. I have done a lot of that on a lot of grounding points to see if that could have been the issue. I put the new coil on the number one cylinder and moved that coil down to the number 2 cylinder. With the new coil ( at top cylinder #1) the spark jumps the 7/16 gap same with #3 cylinder. #2 cylinder won't jump till idle is increased to 1000 rpm for 10 sec. Then very weak at idle. At 1000 rpm it is very strong. New power pack is installed... if the trigger was not working properly I'm assuming I would have no spark on any cylinder? Is this true...so raceone yes and no....I know that's not a very good answer. thank you for the quick response and giving me ideas I really appreciate it.

 

[F_R]

Actually, it has three triggers, one for each cylinder. But I sort of doubt that is the trouble. Tell us exactly how you are testing the spark. An open air gap to ground (not to spark plug)? Do you have anything connected to that coil that should not be? How did you arrive to the conclusion the coil was bad? Finally, I assume you are correct that there is no or weak/intermittent spark, and not something else wrong with the motor. They have a problem with getting water into a cylinder.

 

[palumbo]

yes an open air gap tester. I had a coil go bad all together in the number 2 cylinder that's what started the troubleshooting .replace the coil and have had weak spark at idle sense Just on #2 cylinder. Have flopped coils doesn't seem to be of a coil, new power pack, doesn't seem to clear up the issue. runs greatt at 1,000 rpm and higher. will even run good intermittently at idle you can hear it fire and then start running on 2 cylinders then after sometime and I'll fire again on the number 2 very intermittent, runs excellent at higher rpm

 

[sutor623]

Check the stator as follows:

No spark on One cylinder: 1. Swap the Brown wire with the Brown/Yellow wire and see if the problem moves. If it does, the stator is likely bad.

Another easy test for stator:
Check resistance between the Brown/Yellow and the Brown wire. You should read approximately 450-600 ohms. DVA (peak voltage) should be 150v or more while connected to the power pack.

 

[palumbo]

nothing hooked to the coil that should not be there. yes putting the open air gap to ground not spark plug. I tried it both ways put it to the spark plug that's where I noticed that it's really weak at idle and when I Idle up to 1000 rpm it would start to jump the gap but at idle it would not jump gap.

 

[palumbo]

do not believe I am having a water issue in that cylinder. if it were to have water in that cylinder would that cause weak or no spark? plug looks dry when I take it out no moisture in the cylinder as far as I can tell.

 

[sutor623]

Like I said, check Stator!!!!!!!!

 

[palumbo]

ok thankyou sutor623. ordered a DVA adaptor. waiting for it to arrive. haven't had time to test but once I do will post my findings..thanks

 

[AlTn]

while you're waiting...the pins and socket connections clean and tight?

 

[sutor623]

ok thankyou sutor623. ordered a DVA adaptor. waiting for it to arrive. haven't had time to test but once I do will post my findings..thanks

Sure thing bud. And you can always check resistance of the stator with a basic multimeter. Also, you can swap the brown and brown/yellow wire off the stator and see if the issue moves You will appreciate owning a DVA meter!

 

[palumbo]

so everything checked out just fine, power pack on the coil leads all have right voltage same with stator where they should be at .came to the conclusion that some of the information I gave you was wrong. second Coil from CDI will not fire at idle I was wrong about the number 2 cylinder aS i had moved to the number one. decided I would just order a new coil that's original Johnson Evinrude parts and I thank should fix the problem. my conclusion is the parts (2 so far) that I'm getting from CDI is not compatible with my motor. that's what they recommend I use but its not working. CDI part #183-2303. waiting for my new coil and we'll see what happens. both coils were sold to me at Seaway marine in Seattle . 2 original Coils probably from 1976 looks like one might have been changed at some point, i can put them on the power pack coil leads (3) anywhere and I'll fire just fine. sort of like musical chairs moved the two good coils around the motor several different times and I have great fire everywhere, no grounding issues. put the CDI coil in there will not fire in any three positions on the power pack. except at a higher rpm's. that DVA adapter is awesome. thanks for all your help, I will post my results once my new Original Equipment Johnson/ Evinrude coil arrives.