1 of my 4 spark plug coils is bad - 1982 Johnson 90 hp V4

[ib18]

1 of my 4 spark plug coils is bad - the secondary winding is showing infinitive Ohms instead of 250 ohms, so it is bad. Am I right?

all 4 coils' primary winding are good. They show zero ohms.

The primary winding is the connection between power pack and coil. The secondary (the finer) winding is the connection between coil and spark plug. Am I right?

 

[Bosunsmate]

I dont know but if one is much different from the rest then i would say somethings wrong with it. But infinitive ohms sounds bad

 

[daselbee]

I don't know if I have ever seen such a pitiful example of a video to instruct someone on any subject. The guy doesnt know the subject matter himself. Stop looking at that video. You will not learn anything from this one.

I will get my manual out, and look up the coil specs. I will post back the proper procedure in a few minutes, as the manual is down at the shop right now.

Disregard that video. In fact, I would ask the moderators to takie it down, as it is very very inaccurate.

 

[daselbee]

No Title

This is the correct procedure for testing an ignition coil on a 1996 V6 looper. Ign coil part number is 582508.
Other models' coils will test the same way. There may be variations in what the expected readings should be, but the concept is the same.

For the newbies who are unfamiliar with electronic measuring, zero ohms (0) indicates a direct SHORT between the two points being measured.
Infinite ohms means there is no current flow between the two points being measured, and in different terminology, it means they are OPEN.

Now get this: When measuring the primary side of the coil, it specifies that you should see 0.1 ohms. Todays utility meters will not read 0.1 ohms accurately.
So, when doing this part of the test keep that in mind. The value 0.1 ohms is almost a direct SHORT. It will be very difficult to determine with these junk meters the difference between 0 ohms and 0.1 ohms.

Basically, the test is measuring each of the coils. primary side and secondary side, to the ground tab.
You will probably get 0 ohms on the primary, and around 275 ohms on the secondary side.

EDIT: By the way, on your original post above, where you say "Am I right?"...yes you are in every case.

 

[ib18]

Thanks to each and everyone of you for your first class help and reply. I really appreciate all of your comments. BTW, I found this link thanks to the great internet invention, and confirmed my own diy guesses.

Ignition coil should have between 0.2-1.0 ohm for primary, 200-400 for output (secondary winding) to spark plug.

http://www.outboardignition.com/page40.asp

HP

Year

Power Pack Type

Stator (ohms) Charge | Power

Stator (DVA) Charge | Power

Charge Wire to wire

Power Wire to wire

Trigger (ohms)

Trigger (DVA)

Trigger Wire to wire

Ignition Coil (ohms) Primary | Output

90

1984-1997

CD4

450-600

N/A

150V+

N/A

Brown to Brown/yellow

N/A

35-45

0.5V+

Wht to Blu/Pur/Grn/Pk

0.2-1.0

200-400

 

[ib18]

ok, it turned out my ignition coil was good. I simply took apart all 4 ignition coils, and sanded the ground terminals really clean and shinning. Now, all 4 cylinders have sparks. No new parts needed. Will fire up the motor this weekend and go fishing.

Thanks to all.

 

[ib18]

https://www.youtube.com/watch?v=jf0C9eWDnfc - Johnson 90 hp 2015 cold and first start