1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 Cyl

MattinTally

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1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 Cyl

1988 90hp 3Cyl, serial #B250374 (I have the manual and a DVA tester)

Lost all spark back in July. Did some testing and finally located the blue stator wire that failed the test specified in the book. I ordered a replacement CDI brand Stator and Trigger (decided to replace both since I was taking the flywheel off).

Replaced both and reinstalled the flywheel (had to use a ratchet strat wrapped 2 revolutions around the flyweel and anchored to the aft cleat to prevent the flywheel from turning).

I charged my weak battery up to full charge and did some testing. After new stator & trigger, I now had spark again in the No. 2 and No. 3 Cylinder, but nothing on No. 1. I then swapped the No. 1 and No. 2 coil and the same symptom continued -- good spark on No. 2 and nothing on No. 1. So, I believe the coils to be good.

I then went to the switch box and swapped the No. 1 coil wire and the No. 2 coil wire and retested. The problem moved and I now had good spark on No. 1 and nothing on No. 2. ...... So, this seems to me to point to a bad swtich box (power pack)..... Does everyone concur, or are there other tests I should perform?

1.) Could I have goofed anything up with the installation of either the trigger or the stator? Is there any adjustment to the trigger or stator that I may need to do to get spark back to the No. 1 cylinder? The manual wasn't very helpful in showing exactly how to mount the stator. I belive I've used the same holes, but I can't be positive as the CDI replacement looks different than the OEM part I removed.

2) Is it common for a failed stator to fry a switch box?

3) Does the rectifier have anything to do with the stator/trigger, or could a bad rectifier fry a switch box? I haven't done any testing of the rectifier as I don't think it impacts a no spark issue.
 

scbljr

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Oct 28, 2009
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Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Sounds like you need a switch box as well. Get one from CDI the OEM ones are easily destroyed. I have replaced several on my 1986 115 one cylinder starts miss firing then the whole pack goes out.
 

CharlieB

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Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

A bad stator cannot hurt a switchbox, but a bad switchbox CAN overload and hurt a stator.

Most likely, the switchbox is bad, PROVE it. Swap the trigger leads for 1 & 2, and see if the problem remains on #1 plug, if so you can be certain the box is bad.

A defective rectifier can cause strange ignition problems at speed. Test the rectifier with you ohms meter after disconnecting all the wires. Check battery voltage engine off vs engine running at 1500 - 2000 to verify voltage rise/charging.
 

MattinTally

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Dec 6, 2009
Messages
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Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

A bad stator cannot hurt a switchbox, but a bad switchbox CAN overload and hurt a stator.

Most likely, the switchbox is bad, PROVE it. Swap the trigger leads for 1 & 2, and see if the problem remains on #1 plug, if so you can be certain the box is bad.

A defective rectifier can cause strange ignition problems at speed. Test the rectifier with you ohms meter after disconnecting all the wires. Check battery voltage engine off vs engine running at 1500 - 2000 to verify voltage rise/charging.

I then went to the switch box and swapped the No. 1 coil wire and the No. 2 coil wire and retested. The problem moved and I now had good spark on No. 1 and nothing on No. 2. ...... So, this seems to me to point to a bad swtich box (power pack)..... Does everyone concur, or are there other tests I should perform?



CharlieB,

Isn't reversing the wires from the switchbox to the No. 1 & No. 2 coils an equivalent test to reversing the trigger wires? I think they are, but I want to ask to ensure I'm not missing something or there's a lessen to be learned....
 

Sunfish12

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Feb 6, 2011
Messages
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Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Reversing the trigger wire with a known good cylinder(#2) trigger wire and still have no output on switchbox cylinder one verifies switchbox is bad.
 

MattinTally

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Dec 6, 2009
Messages
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Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Re: 1988 90hp 3Cyl - Lost all spark, replaced Trigger & Stator -- no spark on No. 1 C

Put on a used switch box off a parts motor and reconnected all the wires. Second touch the key she fired right up!

Its working great now...
 
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