Coil wiring surprise!!!

[kaliona]

165hp Mercruiser I6. I've been trying to troubleshoot my intermittent coil spark/no spark problem when I noticed how the coil is currently wired. It currently has 2 brown wires and 1 black wire are on the (+) terminal (black goes to distributor) and 2 white and 1 tan are on the (-) terminal. Everything I've been reading about the coil, along with the wiring diagram in the manual says the brown wires and distributor should be on the (-) terminal.
Is this wiring currently backwards ? I've been running the boat this way all season. I'm confused, if it is backwards, how is the boat running? Could this be why I've always had difficulty starting when the engine is warm? And why I'm having "no spark" from coil problems?

 

[Don S]

Re: Coil wiring surprise!!!

Sounds backwards to me.

 

[kaliona]

Re: Coil wiring surprise!!!

Came back that way from the shop earlier this year. So how is it I've been able to run the boat this way?

 

[Don S]

Re: Coil wiring surprise!!!

They will run, just won't run as well.

 

[stonyloam]

Re: Coil wiring surprise!!!

Came back that way from the shop earlier this year. So how is it I've been able to run the boat this way?

Well look at it this way: You have two sets of windings in the coil, a primary (few turns) and a secondary (many turns). When the points close current (12V) flows through the primary and it sets up a magnetic field, when the points open the current stops flowing and the field collapses and generates a very large voltage in the secondary. It does not make any difference which way the current flows through the primary, the only difference would be when hooked up backwards the primary and secondary common connection would be on the wrong side of the primary windings, so I guess it would work, but the efficiency would be reduced due to the resistance of the primary windings. Anyway that is how I think it works.

 

[kaliona]

Re: Coil wiring surprise!!!

For the last year, I've been battling a problem of difficulty starting the engine when it's warm. Could this have been the cause off that problem?

 

[Don S]

Re: Coil wiring surprise!!!

Why ask??????? Put it right, and find out.

 

[guycooper]

Re: Coil wiring surprise!!!



Well look at it this way: You have two sets of windings in the coil, a primary (few turns) and a secondary (many turns). When the points close current (12V) flows through the primary and it sets up a magnetic field, when the points open the current stops flowing and the field collapses and generates a very large voltage in the secondary. It does not make any difference which way the current flows through the primary, the only difference would be when hooked up backwards the primary and secondary common connection would be on the wrong side of the primary windings, so I guess it would work, but the efficiency would be reduced due to the resistance of the primary windings. Anyway that is how I think it works.

I'm having the same problem

 

[GA_Boater]

I'm having the same problem

Have you been running for 8 1/4 years with the coil wires reversed?

Closed.