On a recent trip we had light winds and had to motor in. I started the Atomic 4 and motored for about an hour when she suddenly quit. It was so calm a stop that it was as if I had simply shut the ignition switch (yes, we had gas.) I could not start her again. The next day the motor started up. The day after that I motored for about 45 minutes out, cut it, drifted for a few hours and then motored back in. Any ideas regarding the initial quit?
Atomic 4 Stall
- Thread starter Temboguazu
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Make sure all electrical wires to engine are in good condition and tight, alternator, ignition, etc. A grounded wire can interrupt the ignition circuit. When an engine suddendly quits with no sputtering it is usually an electrical failure.
My old A4 had a bad connection somewhere in the ignition system which caused the occasional stall and random start/no start. Usually the no start was when I really needed it to start!
I solved it by replacing the harness and from that point forward never had a problem....with the ignition system, that is.
I have a diagram on my computer of a temporary solve that was shown to me by one of the mechanics down here and when I get back from the boat will try to find it and post it.
Be sure that's the problem before you fork out the cash for a harness, though since you problem may be something else.
I solved it by replacing the harness and from that point forward never had a problem....with the ignition system, that is.
I have a diagram on my computer of a temporary solve that was shown to me by one of the mechanics down here and when I get back from the boat will try to find it and post it.
Be sure that's the problem before you fork out the cash for a harness, though since you problem may be something else.
For example is there power reaching the ignition coil when it fails ?
While i can only WAG on your issue and you need to test to avoid throwing parts at the problem
the coil is one of the items that can fail when hot and work when cool
While i can only WAG on your issue and you need to test to avoid throwing parts at the problem
the coil is one of the items that can fail when hot and work when cool
Suggestions:
1. Check your ENGINE GROUND. The electrical system is connected through the GROUND STRAP on the engine. If this ground connection and its connector is corroded, the engine heat will 'dry out' the 'corrosion' and render it non-conductive .... slowly. When the engine cools and moisture re-saturates, the corrosion conductivity returns, .... only to dry-out later to repeat the symptoms. Ditto with all other 12vdc connections to the engine.
2. When was the last time you torqued the head? This is a studded engine and the studs that hold the 'head' on are subject to miniscule 'stretch' over time and repeated heat swings. If you dont occasionally re-torque, expect to eventually 'blow' a head gasket (usually between cylinders 3 & 4).
Check the compression both when the engine is cold and again when the engine is HOT.
and all the other suggestions by the other posters .... and my best 'bet' is a failing coil or failing 'oil pressure safety switch' if you have one.
1. Check your ENGINE GROUND. The electrical system is connected through the GROUND STRAP on the engine. If this ground connection and its connector is corroded, the engine heat will 'dry out' the 'corrosion' and render it non-conductive .... slowly. When the engine cools and moisture re-saturates, the corrosion conductivity returns, .... only to dry-out later to repeat the symptoms. Ditto with all other 12vdc connections to the engine.
2. When was the last time you torqued the head? This is a studded engine and the studs that hold the 'head' on are subject to miniscule 'stretch' over time and repeated heat swings. If you dont occasionally re-torque, expect to eventually 'blow' a head gasket (usually between cylinders 3 & 4).
Check the compression both when the engine is cold and again when the engine is HOT.
and all the other suggestions by the other posters .... and my best 'bet' is a failing coil or failing 'oil pressure safety switch' if you have one.
If the boat is old and it has the original igniton
key switch you should replace it. People who have old classic cars tend to run into that problem. Most cars are not around long enough for that to occur so few are familiar with that problem. When replacing the switch be sure that the drain hole in the body of the switch is pointed down for good drainage.
Coils are rarely a problem but when they do go bad one of the symptoms is that they act up as the engine heats up. Another coil symtom is misfire at high rpms and not so much at lower rpms.
Condensers are touchy and can produce a number of peculiar symtoms. Condensers are also notorious for being bad, brand new right out of the box. When tuning up, always swap out the new condenser and start the engine up before you swap out the other items so as to verify if the new one is OK.
key switch you should replace it. People who have old classic cars tend to run into that problem. Most cars are not around long enough for that to occur so few are familiar with that problem. When replacing the switch be sure that the drain hole in the body of the switch is pointed down for good drainage.
Coils are rarely a problem but when they do go bad one of the symptoms is that they act up as the engine heats up. Another coil symtom is misfire at high rpms and not so much at lower rpms.
Condensers are touchy and can produce a number of peculiar symtoms. Condensers are also notorious for being bad, brand new right out of the box. When tuning up, always swap out the new condenser and start the engine up before you swap out the other items so as to verify if the new one is OK.
It could be anything. Electrically it could be a bad ignition switch causing intermittent running, bad coil, bad pickup, (points/condenser), bad ground, etc., etc..
I was given a car once that no one could figure out to get running. He had it to several shops, spent $$$$$ on lots of new parts, but it refused to run, would only occasionally spit and sputter. Turned out the wire to the coil was open internally. So while your checking continuity, make an effort to move the wires around and wiggle connections.
I was given a car once that no one could figure out to get running. He had it to several shops, spent $$$$$ on lots of new parts, but it refused to run, would only occasionally spit and sputter. Turned out the wire to the coil was open internally. So while your checking continuity, make an effort to move the wires around and wiggle connections.
Never and rarely are the ones that will sneak up on you, especially on an old boat. But I always start with electrical because its the weakest system and the most prone to failure. Only after it checks out do I move on to fuel. And as you say, fuel usually isnt intermittent like that. But notice I said "usually", lol. Its always the one you say its not, and the last one you check, ya know.
I go with the electrical issue. only exhibits when heated up, then when engine cools runs ok. Classic. make sure all wires are off the block away from heat scources. take each connection off and wire brush the contacts and replace. look for cooked or cracked insulation. Replacing the wire harness would do it for any of the above problems. Redo the connections with silicone grease after a good cleaning with wirebrush or emery cloth. Very frustrating. only fuel type problem that would look like this would be vapor lock of the carb when hot, but that usually effects restarting while hot and dosent cause a shutdown lwhile running.
Jack Manning mentions a good possibility. I have dealt with a faulty harness for a diesel engine but since the diesel doesn't not require electricity to run never considered it as a possible cause for engine stalling. Since the A-4 is an electrical ignition driven engine a faulty harness can shut the engine down. The wiring harness on a boat is susceptible to chafing. These harnesses are routed around some sharp fiberglass bends and with years of hull flexing the wire insulation tends to wear off and cause electrical shorts. These failures usually start gradually and intermittently and quickly progress to total failure. I would suggest you visually inspect the harness from control panel to engine and look for broken insulation. Even if this does not turn out to be the problem a visual inspection may save you some aggravation in the future. Not every time a damaged wire can be detected visually so a continuity test could be performed on all leads but most often than not it can be detected visually.
I'd also suggest that you check the vent on your fuel tank. If it's plugged you could be pulling a vacuum in the tank that the fuel pump can't over come. Simply running the engine till it shuts down and opening the tank filler will tell you. If there is a woosh of air rushing in then it may be a clogged vent.
As for the coil once it shuts down pull the coil wire and crank the engine, If you have spark it's good. If not it's bad.
As for the coil once it shuts down pull the coil wire and crank the engine, If you have spark it's good. If not it's bad.
George, a weak coil might still give a spark under
some conditions. The symtoms described are characteristic of a weak coil although there are other situations that could be doing it.
some conditions. The symtoms described are characteristic of a weak coil although there are other situations that could be doing it.
True enough, But that is easily detected. The spark should be a hot blue white spark, if you've got a yellowish thin spark then you have a problem.
I'm not a fan of spray and pray repair, rather I prefer to test and rule out components until the problem is confirmed. An hour of your time saves more than a dime.
Here's what I do next time
When it stalls, LEAVE everything alone!
PPull a spark plug wire, insert a plug and lean it against the block or a lead to ground it.
Check for spark, should be nice blue,
No spark?
Pull the dist cap off, the pints opena nd close, causing a drop in voltage at coil and poof big voltage, low amps, (hense whyu you never touch a spark plug wire, give it to your no so freinds to hold!).
Turn the en gine til the points are CLOSED. take a ????, screw driver, small stick, anything and OPEN the points, you shold see some type of spark just as they open/close.
If not, take a mulit meter and see if there is 12 volts TO the points.
If there is swap out the condenser, (most times they fail totally, but...)
If no 12 volts keep going back to the ign switch checking to see if voltage is there.
If you have spark there, but not at spark plug, coil is bad.
Can double check the coil, check the ohms resistance across the coil.
If it has spark, take the airfilter off, see if there is gas going to the carb, (you can take the fule line off and crank or giggle the line, but be CAREFUL!!! GAS LIKES TO CATCH ON FIRE AND RUIN YOUR DAY!!
Get a can and crank it over, see if it comes out.
If not, take the cap off the tank, hear a hiss????, then the cap is making a vacuum, no his the fuel pump got hot and quit
You gotta do it when it get hot, not when you get time.
Can you run it at the dock and get it to quit?
Good luck and let us know
Joe
I thought only cars and motorcycles did this hair pulling out problems!
When it stalls, LEAVE everything alone!
PPull a spark plug wire, insert a plug and lean it against the block or a lead to ground it.
Check for spark, should be nice blue,
No spark?
Pull the dist cap off, the pints opena nd close, causing a drop in voltage at coil and poof big voltage, low amps, (hense whyu you never touch a spark plug wire, give it to your no so freinds to hold!).
Turn the en gine til the points are CLOSED. take a ????, screw driver, small stick, anything and OPEN the points, you shold see some type of spark just as they open/close.
If not, take a mulit meter and see if there is 12 volts TO the points.
If there is swap out the condenser, (most times they fail totally, but...)
If no 12 volts keep going back to the ign switch checking to see if voltage is there.
If you have spark there, but not at spark plug, coil is bad.
Can double check the coil, check the ohms resistance across the coil.
If it has spark, take the airfilter off, see if there is gas going to the carb, (you can take the fule line off and crank or giggle the line, but be CAREFUL!!! GAS LIKES TO CATCH ON FIRE AND RUIN YOUR DAY!!
Get a can and crank it over, see if it comes out.
If not, take the cap off the tank, hear a hiss????, then the cap is making a vacuum, no his the fuel pump got hot and quit
You gotta do it when it get hot, not when you get time.
Can you run it at the dock and get it to quit?
Good luck and let us know
Joe
I thought only cars and motorcycles did this hair pulling out problems!
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