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1redTA
07-04-2011, 12:21 PM
I am having issues with the starting circuit in my boat, been thru a bunch of solenoids and replaced the ignition switch. The distributor has a Petronix ignition and coil( no resistor ), one wire alt, a good charged battery

I have had the volt meter out and checked for voltage
Batt 12.6 Solenoid batt side 12.6
Ignition switch 12.6 B
Ignition switch 12.6 I
Ignition switch 12.6 S all with key in the correct position

The starter won't even try to turn over, no matter how I hook up anything. no voltage to starter side of the solenoid
One day it was running, quit and now all this fun!
I could use a schematic for the wiring of an 81 Skier 351w powerslot. I have used the search but can't find a good schematics.
Thanks and Happy 4th!

JLeuck64
07-04-2011, 02:16 PM
Are you getting a click at the relay when the key is turned to the start position? If no then perhaps the starter relay is not grounded well. If I remember correctly those relays are remote and not physically attached to the starter motor but are found on the back of the engine. The ground is the metal case of the relay and the bracket it is attached to. That connection needs to be clean and tight of course.

Now if that relay is clicking but the starter is not turning over we need to know what the voltage is at the starter motor during cranking. If it is low or zero then the contacts in the relay are probably burnt again, but what could be causing that to keep happening? One thought I have is maybe the starter motor is turning to slow when cranking. A slow running motor will cause a LOT of current to flow thought the circuit. Replacing the relay will temporarily solve the no crank symptom but doesn't fix the under lying problem. You can try another starter relay but we'll need to do some more testing after the motor is cranking to check the starter circuit for abnomal voltage drops.

jconover
07-04-2011, 03:26 PM
12V across neutral safety switch?

1redTA
07-05-2011, 06:18 PM
I got the relay from autohole and it won't do click.
When I got the boat the solenoid had the ignition and starter wires on the I terminal of the solenoid and both of the neutral safety switch wires on the S terminal. It rangreat likes this all last year, lately the solenoids haven't been lasting long at all.

Can someone tell me how there S S is hooked up on the solenoid.

TxsRiverRat
07-05-2011, 06:26 PM
I had to open this thread...

I was like... You have a short.. what?

:uglyhamme:uglyhamme:uglyhamme:uglyhamme

1redTA
07-05-2011, 07:10 PM
I had to open this thread...

I was like... You have a short.. what?

:uglyhamme:uglyhamme:uglyhamme:uglyhamme

you weren't expecting pictures were you?

jconover
07-05-2011, 07:18 PM
Start power comes from the Ignition wire in the harness (which is yellow/red stripe), which passes through the neutral safety switch, and then goes to the S (start) terminal of the starter. The NSS is normally closed when the boat is in neutral, and open otherwise, preventing you from starting the boat if it is in gear. If both wires go from the NSS to the S terminal, then it is not doing anything.

The I terminal on a starter goes to 12V when the S terminal is energized. In my previous electrical setup, I ran the ballast bypass wire from this terminal to the cold side of the ballast resistor. This functionality allows you to deliver momentary 12V power to the ignition system while cranking the engine. Without it, you would only be delivering 7-9 volts to the ignition system during cranking, since the ballast resistor pulls down the voltage from the ignition so that you don't burn out your ignition system. (Note that some ignition systems have internal resistance which compensates for the ballast resistor - they are typically called solid state coils, and can be identified by the fact that they have a 1.4 Ohm internal resistance when disconnected from the ignition system)

A few pictures attached - note that I used a white wire from the terminal block to the neutral safety switch.

Edit: you have an external starting solenoid, but the functionality is the same - S terminal gets 12V from yellow/red wire via the NSS when everything is hooked up properly. If testing for functionality, you can bypass the NSS and go directly to the S terminal. When I bought my boat, owner had done one step further and bypassed the starting circuit with an SPST switch and some electrical cord - the switch just bridged between 12V and the S terminal directly. Ugly hack (picture attached).

1redTA
07-05-2011, 10:35 PM
Thanks for the pics jconover, I'm going to try some new runs this weekend

1redTA
07-07-2011, 01:12 PM
so does the S wire on the ignition go to the S on the starter solenoid? and where does the I terminal run to, the ignition coil?

jconover
07-07-2011, 01:46 PM
Do you have a ballast resistor in there? I have nothing connected to my I terminal any more

1redTA
07-07-2011, 02:24 PM
no ballast resistor, where does the coil get it's power from then

jconover
07-07-2011, 03:07 PM
The coil needs 12V whenever the keyswitch is in any position other than OFF or ACC. This is normally provided by the purple wire that comes from the dash, via the harness, to the distribution block at the back of engine. The reason you use the purple wire is because it is also run through the safety breakaway switch on the dash.

In any case, the "I" terminal of the starter is only hot when cranking. The I terminal has no connection when the starter is at rest, and is +12VDC while cranking.This circuit provides +12VDC to the ignition coil during cranking for easier engine starting. So you wouldn't want to hook your ignition coil to that.

jconover
07-07-2011, 03:12 PM
By the way... if your starter DID have a wire going from the I terminal to the + side of the coil.. that is the ballast bypass wire (meaning either your boat DID have a ballast resistor, or still does and you misidentified it). On my wiring, the I terminal went to the ballast resistor, which was then in turn wired to the + side of the coil.

Again - the I terminal is only +12V when cranking... when wired this way, it provides your ignition system with extra "umph" to start the motor. as soon as you stop cranking, "I" goes to zero volts, and your coil is getting its voltage from the purple wire in the harness (trace this to see what it passes through)

Reference:
http://forums.vintage-mustang.com/vintage-mustang-forum/549268-s-terminal-starter-relay.html#post3452257

TxsRiverRat
07-07-2011, 03:13 PM
you weren't expecting pictures were you?

LMAO - haiiiil noooo