68 startflite 100-s wont turn off

[elfking]

Hi all,
I did a little R&R on a boat I was given since all the wires were just flaking away from being original. Everything works perfect except when I turn the key to the off position the boat will still be running off of the charging system. It will eventually sputter and die, but sometimes will run for quite a while.

A little info:
It has an after market pulse pack and coil and I have replaced the rectifier and voltage regulator. I also replaced the pulse pack (as this was the reason I got the boat..) It has an electric start, and electric shift.

I am not a newbie to electronics/re-wiring things but honestly I haven't dealt with a generator + rectifier + voltage regulator.. They have all had alternators and a regulator.

I have been trying to put a diode in place to keep the system from back feeding but I have been unsuccessful. My next train of thought is to take a relay and have it close the field when the key is off. Unless there is an easier way I am just overlooking.

I have the factory service manual, I will try to scan the wiring diagram if people need that to assist..

I have also looked around a bit and found a couple threads like this one:
http://forums.iboats.com/showthread.php?t=69310

I will have a look to see if I have these wires, I don't remember there being a black and yellow wire on my pulse pack.. I also have NO ground wire to my ignition switch. There is a ground there but the switch itself has no ground, so its only connected to the lights/gauges... I made sure there was a really good ground for everything in the motor.. so maybe I mixed up something here which needs to only be grounded while its running and then when the ground is taken away the pulse pack no longer sparks...?

Thanks for you time.

 

[Joe Reeves]

Re: 68 startflite 100-s wont turn off

There is no diode required on that system. Study the wiring diagram. It appears that you have something wired incorrectly.

If when the engine is not running, and with the key in the OFF position, there is no voltage being applied to the pulsepack...... and still with the engine not running but with the key in the ON position, there is voltage being applied to the pulsepack..... that much is normal.

Now, after starting the engine, then turning the key to the OFF position, the engine continues to run..... obviously voltage is still being applied to the pulsepack. This indicates that the charging system is somehow throwing voltage directly to the pulsepack.

If wired correctly, this would be impossible on that model. Has other wiring/components been added?

 

[darrklim2]

Re: 68 startflite 100-s wont turn off

I will have a look to see if I have these wires, I don't remember there being a black and yellow wire on my pulse pack.. I also have NO ground wire to my ignition switch. There is a ground there but the switch itself has no ground, so its only connected to the lights/gauges... I made sure there was a really good ground for everything in the motor.. so maybe I mixed up something here which needs to only be grounded while its running and then when the ground is taken away the pulse pack no longer sparks...?

If the key isn't grounded how else would it shut the motor off. From what I understand the engine is "shut off" when the key grounds out the spark, without a ground I don't think this would work??? Maybe I am completely wrong but that is my guess.

 

[Joe Reeves]

Re: 68 startflite 100-s wont turn off

Darrklin.... The 1968 100hp model is unlike the later models that require killing the ignition (grounding).

This model actually requires battery voltage to energize the pulsepack, and to turn it off, it's simply a case of eliminating that voltage, similar to a automobile ignition system.

 

[darrklim2]

Re: 68 startflite 100-s wont turn off

Darrklin.... The 1968 100hp model is unlike the later models that require killing the ignition (grounding).

This model actually requires battery voltage to energize the pulsepack, and to turn it off, it's simply a case of eliminating that voltage, similar to a automobile ignition system.

Thanks Joe for the clarification. I wasn't sure if it was the same back then, I haven't worked on many older models.

 

[elfking]

Re: 68 startflite 100-s wont turn off

Thanks for the info, I thought about the pulse pack being energized idea with voltage. So I had a wire coming directly from the key ign post to the purple wire on the pulse pack. Which was hooked in with the ign system. I figured this would kill it when I turned the key off. However it didn't. Maybe the ignition switch (is original) and is not cutting off and voltage is still slipping past it..

Or maybe I have the wrong wire?

Thanks for all the help.

The only other major change I did was the following:

It used to have an amp gauge which had the output from the charing system going all the way to the front just for the gauge then back again to complete the loop. I updated to a volt meter and shortened these wires, so it wasn't running forwards then back again. This seemed like a very poor way of wiring a system. Plus a volt gage will show you plenty. So I just have one lead coming for power from the starter solenoid to the ignition key.

The key wasn't interrupting the charging system at all when it was coming forward for the gauge, it was only getting power for the key from this lead.

There is no diode required on that system. Study the wiring diagram. It appears that you have something wired incorrectly.

If when the engine is not running, and with the key in the OFF position, there is no voltage being applied to the pulsepack...... and still with the engine not running but with the key in the ON position, there is voltage being applied to the pulsepack..... that much is normal.

Now, after starting the engine, then turning the key to the OFF position, the engine continues to run..... obviously voltage is still being applied to the pulsepack. This indicates that the charging system is somehow throwing voltage directly to the pulsepack.

If wired correctly, this would be impossible on that model. Has other wiring/components been added?

 

[elfking]

Re: 68 startflite 100-s wont turn off

I scanned the wiring diagram in case it will help jog any ideas. If this is against any TOS agreement or something please let me know right away and I will remove it. I scanned it from my Evinrude Factory Service Manual.

http://sirelfking.home.comcast.net/boat/68starflite100-s-wiring-diagram.jpg

Of course this does not show the after market CDI/pulse pack setup. This diagram is straight as it came from the factory.