Inline 6 ignition

[JSavage]

Friends, fellow boaters... and everyone else, I've a question.

First the background.

Last year I lost half of my ignition on this 90 HP merc, inline 6, circa 1985.

I replaced a switch box, believing it to be the culprit, though without a DVA to confirm. It didn't correct the problem. I them purchased a new stator, still no joy.

Well this year, I decided to by a DVA and get to the source of the problem.

I tested the stator and got 180 and 30 as required.

When I checked the coils I got 25, 1.5, 22, 1.5, 25, 1.5

It occurred to me that something was off. I removed the "new" CDI switch box and re-installed the Merc box that I took off last year. I re-measured at the coil and got .1, 1.8, .1, 1.7, .2, 1.8

Now it hits me "Maybe that CDI box puts out a different voltage! Could that make my boat run WORSE, mixing the switch boxes? It in fact did run worse with the CDI box and I had a tough time even setting timing.

Any input would be great.

Thanks.

My Bad, it was a Mallory switch box.

 

[daveswaves]

Re: Inline 6 ignition

Friends, fellow boaters... and everyone else, I've a question.

First the background.

Last year I lost half of my ignition on this 90 HP merc, inline 6, circa 1985.

I replaced a switch box, believing it to be the culprit, though without a DVA to confirm. It didn't correct the problem. I them purchased a new stator, still no joy.

Well this year, I decided to by a DVA and get to the source of the problem.

I tested the stator and got 180 and 30 as required.

When I checked the coils I got 25, 1.5, 22, 1.5, 25, 1.5

It occurred to me that something was off. I removed the "new" CDI switch box and re-installed the Merc box that I took off last year. I re-measured at the coil and got .1, 1.8, .1, 1.7, .2, 1.8

Now it hits me "Maybe that CDI box puts out a different voltage! Could that make my boat run WORSE, mixing the switch boxes? It in fact did run worse with the CDI box and I had a tough time even setting timing.

Any input would be great.

Thanks.

My Bad, it was a Mallory switch box.

The switch boxes do not put out appreciably different voltage, however, it is not uncommon for a failing or failed switch box to damage the remaining one. There is a bias connection between the two. It is generally recommended to change the switch boxes as a pair, expensive I know, but it sounds like your other switch box may be bad as well.

 

[JSavage]

Re: Inline 6 ignition

I just realized I never closed this out. In fact, I did replace the remaining switch bax and solced the problem.... then I sold it. Thanks for the help!