1981 EVINRUDE SHUT DOWN 70HP

frydaddy5

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Oct 11, 2013
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LAST NIGHT MY 1981 70HP EVINRUDE JUST SHUT DOWN LIKE YOU TURNED THE KEY OFF. HAD JUST GOTTEN THROUGH FLOUNDERING AND PUT THE MOTOR DOWN, GOT ON A PLANE AND WENT A LITTLE BIT AND IT WAS LIKE SOMEONE TURNED THE KEY OFF. CHECKED ALL OF THE OBVIOUS AND KEPT TRYING TO CRANK , ACTED LIKE IT WASN'T GETTING FIRE, THEN IT CRANKED. IDLED IT UP AND IT DIED DOWN AND NEVER WOULD CRANK AGAIN. HAD TO BE TOWED. ANY SUGGESTIONS AND HOW TO TROUBLE SHOOT WHAT YOU THINK IT IT IS.

THANKS,
FRYDADDY5
 

Crosbyman

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The "cranking circuit" is very basic....fire or not on the spark plugs cranking malfunctions are likely the result of .
.
- weak battery (not charging, old, defective etc... check or try a new charged battery)
- poor electrical contacts ...anywhere (batt post, selenoid, starter etc...incl poor contacts in the start key, neutral switch, internal selenoid contacts etc...

start with the basics with a a fresh battery and connections

my 2 cents
 

frydaddy5

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Oct 11, 2013
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WILL TRY THAT FIRST, THEN BY PASSING THE NEUTRAL SWITCH TO SEE IF THAT MAKES A DIFFERENCE. STARTER ENGAGED AND SPUN THE MOTOR, ANYWAY TO CHECK THE POWER PACK OR DO YOU THINK IT WOULD HAVE RESTARTED THAT LITTLE TIME IF IT WERE BAD? JUST CONFUSED ON IT JUST SHUTTING DOWN.
 

boobie

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When you say "won't crank", do you mean the motor won't spin over or won't start.
 

Crosbyman

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Frydaddy5....keep this clear and orderly

are we having a mechanical issue here (no flywheel revolutions when key is START)

or are we having a fuel combustion issue ( motor won't run after being successfully cranked over with the START key ??
 

frydaddy5

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Oct 11, 2013
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FLYWHEEL TURNS, MOTOR SPINS, STARTER WORKS FINE-NO DRAGGING , IT'S LIKE IT LOST THE FIRE. CLEANED BATTERY POST, MADE NEW CONNECTIONS GOING TO THE FUSE BLOCK FOR THE KILL SWITCH, REMOVED AND CHECKED THE NEUTRAL KILL SWITCH EVERYTHING JUST FINE THERE. STILL DON'T UNDERSTAND IT CRANKING AFTER INITIAL SHUTDOWN. WOULD A POWER GO OUT COMPLETELY, THEN RESTART ONE TIME AND GO OUT ON ALL 3 COILS?
 

frydaddy5

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THE LAST TIME I HAD A POWER PACK GO BAD IT ONLY SHUT DOWN ONE COIL, STILL HAVEN'T LOOKED IN THE CONTROL BOX. ANYONE KNOW HOW TO MAKE A HOME MADE SPARK CHECK OR IS THIS AN ITEM YOU CAN GET AT A REASONABLE PRICE?
 

boobie

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You can buy open air gap spark testers at most parts houses for around $8.00. If you get one set it at 7/16". Another thing to do is disconnect the black/yellow wire coming out of the power pack and try it. This eliminates the boat wiring harness.
 
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frydaddy5

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IF THE BLACK/YELLOW IS DISCONNECTED WILL IT TURN OFF IF IT WERE TO CRANK? DOES THE SPARK CHECKER CHECK THE SPARK BETWEEN THE POWER PACK AND THE COILS OR IS IT COMING OUT OF THE COIL? A FRIEND TOLD ME IT CHECKS IT COMING OUT OF THE COIL, DOESN'T SEEM LIKE THAT WOULD BE THE CASE SINCE IT WOULD BE AFTER THE COIL. WILL GET ONE FROM THE AUTO STORE AND LOOK FOR A RESPONSE ON WHERE IT CHECKS IT. THANKS FOR RESPONDING.
 

Bosunsmate

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The black yellow kills the engine when grounded. This happens when the key is in the off position- it connects that wire to engine ground. If theres a faullt in the boat wiring or the key switch then disconnecting that wire stops that grounding from happening. If disconnecting it works and the engine then goes you need to use the choke to stop it.
Just put the sparktester at the end of the coils grounded to the block that way if its firing you check the whole electrical system except timing.
 

Silvertip

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You keep using the word "crank" when you should be using the word "start" or "fire" for your situation. An engine is cranking when the starter is spinning the flywheel. Doesn't matter if the engine "starts" or not. That's cranking. The battery is not even required for your engine to actually "run" so the electrical checks on that system were, as you found out, a waste of time. An engine that suddenly stops is almost always an ignition system issue. Have you at least pulled the plugs to see if they are wet, dry, oily, etc. If they are wet, that says you do not have a fuel problem. If they are dry you may have a fuel problem. But since you have a spark checker, confirm that you do or do not have spark on all cylinders. The neutral start switch prevents the motor from "cranking" in forward or reverse. It does not kill the ignition system. The KILL switch (if you have one) would kill the engine immediately if the lanyard was accidentally pulled or if the switch itself was defective. If this is a spark issue, then understand that electronics go bad in many different ways. Sudden death, intermittently, once in a blue moon, fail on one cylinder followed by failure on the next, or failure on all cylinders, etc. Yes, a bad module can kill the engine once, let it restart once, and then head off to module heaven.
 

boobie

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One must be careful when answering questions on here. The term "won't crank" when used in the Southern States usually means won't start. I learned that over 20 years ago. Nothing wrong with it though.
 

frydaddy5

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SORRY FOR NOT KNOWING THE LINGO, YEA, I'M IN THE SOUTH. FLORIDA PANHANDLE, PENSACOLA. THE PLUGS WERE SOAKING WET WHEN PULLED, I DID CHECK THE KILL SWITCH AND PUT NEW BATTERY CONNECTORS ON THE FUSE BOX WIRES SINCE THE KILL SWITCH IS HOOKED TO THE FUSE BLOCK. DID A COMPRESSION CHECK, ALL THREE ON A COLD TEST, FROM THE TOP, WERE 125, 122, AND 125. HOOKED THE KILL SWITCH BACK UP AND FIRST SPIN THE MOTOR STARTED. GO FIGURE.

I'M NOT CONVINCED THE PROBLEM WAS WITH THE BATTERY CONNECTIONS FOR THE FUSE BLOCK, I FOUND MAYBE 3 WIRES BROKEN OUT OF THE 8 WIRES AT THE OLD CONNECTOR. NONE OF THE WIRING FROM THE STATER OR TIMING ADVANCE LOOKED WORN OR ANYTHING.

MY NEXT GUESS IS TO OPEN UP THE CONTROL BOX AND CHECK THE IGNITION SWITCH AND SPRAY WITH SOME ELECTRONIC/CONTACT CLEANER. ANY OTHER SUGGESTIONS ARE WELCOMED. IF I'M NOT REFERRING TO SOMETHING CORRECTLY, I APOLOGIZE AHEAD OF TIME. YOU KNOW US SOUTHERNERS. IF THAT ALL CHECKS OUT, NEXT WEEKEND I'LL TAKE IT TO THE LAUNCH, LEAVE IT ON THE TRAILER AND RUN IT FOR ABOUT AN HOUR AND THEN SEE WHAT HAPPENS AT FULL THROTTLE FOR A WHILE AND SEE IF THE SHUT DOWN OCCURS AGAIN.
 

boobie

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Well hell, you live in LA. That means Lower Alabama. I used to live in Pensacola and loved it.:joyous: Take it out and run it and report back. By the way, I'm a Northern Midwesterner.
 

Watermann

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My 55 HP Johnny did the same thing to me, running great and one day at WOT it died like the key was turned off. After about a half hour it fired up again and I almost made it back to the launch before it died again. It was the power pack that went bad.
 

frydaddy5

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Oct 11, 2013
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FLOUNDERING IS REFERRING TO THE FLOUNDER FISH, FLATTIES AS WE CALL 'EM DOWN HERE. YOU GO AT NIGHT WITH LIGHTS MOUNTED ON THE FRONT OF THE BOAT AND LOOK FOR FLOUNDER FISH LAYING ON THE BOTTOM AND STICK 'EM WITH GIGS. NOVEMBER IS THE BEST MONTH TO GIG FOR FLOUNDER IN THIS AREA, IF YOUR MOTOR DOESN'T CRAP OUT ON YOU.

THANKS FOR REPLY WATERMAN, I'M STILL THINKING ITS THE POWER PACK BUT WILL TRY EVERYTHING ELSE TO TRY AND RULE OUT ANY OTHER PROBLEM BEFORE FORKING OUT THAT $180. THIS PACK HAS BEEN RUNNING FOR ALMOST 11 YEARS AND IT IS AN AFTER MARKET. THE ORIGINAL LASTED 22 YEARS. IF I DO END UP BUYING ANOTHER ONE, IT WON'T BE ANOTHER AFTER MARKET.

NOT FUN BREAKING DOWN AT NIGHT NEAR THE CHANNEL, WE HAVE A LOT OF BARGE AND CONTAINER SHIP ACTIVITY AT NIGHT DOWN HERE. I'M JUST GLAD WE HAD A BIT OF A NORTH WIND THAT BLEW US BACK NEAR SHORE OUT OF THE WAY OF TRAFFIC. DON'T LIKE THE IDEA OF HAVING TO LIGHT THOSE FLARES OFF WHILE STANDING IN THE BOAT, BUT WOULD HAVE IF IT WAS CALLED FOR. RAINED TODAY SO I COULDN'T CHECK THE CONTROL BOX, BACK TO WORK TOMORROW. WILL HAUL IT TO THE WATER NEXT WEEKEND AND SEE IF IT DOES THE SAME THING, BUT, I WILL DO IT DURING THE DAYTIME WITHOUT TAKING IT OFF THE TRAILER. THANKS AGAIN FOR ALL THE INPUT AND WILL HOPEFULLY HAVE SOME NEWS WHEN I DO.
 
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