Atomic Four -- No Spark

[tchiffriller]

I was motoring into port when i stupidly cut the channel and immediately threw it into reverse without even slowing up the throttle. It revved up high in neutral and I panicked and thru it into reverse where it immediately cut off. Since then the engine will crank but there is NO SPARK i have since then replaced the coil which i believed to be faulty and still no spark. Do you think the over rev or boat hitting the sandy chesapeake with a thud do something to the ignition system?? Any advice would be much apreciated!!!

[5.5 Meter]

Open up the distributor to see if the router is rotating.

[Tom Robb]

If the distributor rotor is NOT rotating, something mechanical in the engine is busted - cam chain, distr. gear, etc.

[Peter Malcolm Jardine]

Almost impossible to break that engine... you should be doing points and condenser once a year anyway.

[Plover]

If you have an electronic fuel pump some of them are wired to a pressure switch and in some cases people wire the ignition into them to keep from burning out the points. Check all of that wireing as well as oil level. But as said above, check the rotor, the advance springs, advance weights, replace the points and condenser check all conections. Its a very simple motor, it either a loose wire, a bad switch, or something let go, with any luck, it just a roll pin and not gear teeth. If you took the teeth off the cam you will be pulling that engine! These engines won't jump time and they are pretty hard to break!
Best of luck
Paul

[Michael D. Storey]

Suggest you take the distributor cap off and turn on the ignition. Open the points and look for a spark. No spark, your prob is at least partially in the distributor. It has often been sed that in points-and-condenser ignition, 90% of your break downs are electrical.
I highly doubt that the revving/plow into the sand thing is a source of your prob. I would also suggest that you take out a couple of plugs and turn over the engine by the fly wheel. Watch the rotor. Check the timing then, too, by seeing if you are pointing to #1 cylinder when you are on your timing marks. But, if there is no spark, timing is not the issue. It may be a coincident issue, but I doubt that it is. I am wondering about the point spring, actually. I knew a guy from Hoopers Isle over on the Shore who had a Draketail, as well as a boat with an Atomic Four. He was headed to Solomon's Island, and his spring broke, so he rigged it with rubber bands, at least he sed he did.

[banjoman]

All good advice so far. The only thing I would add is to call these guys.

http://www.moyermarine.com/

You will probably end up speaking with Don. He knows his stuff.

[tchiffriller]

Heres an update!! I went to my grandparents house where i keep the boat this weekend and replaced the spark plugs, coil, and spark plug wires. I then took off the distributor cap and the points were nice and white so then i cleaned the distributor cap and put everything back together. I then hooked up a spark plug to test for spark to the #1 wire and I got a BIG JUICY spark. Naturally I was very excited and and put the plugs all in and put all of the plug wires on and yet i cranked the engine to no avail!!!! it wouldnt start. So i took out the #1 spark plug to make sure i still had spark... and no spark!!! what could it be???

an intermitten problem?
i hope not

or maybe something changed between the two time?

could it still be the condenser?

[ssor]

I once had a bad ignition switch that wouldn't connect power to the spark coil while in the engine cranking position. If I got the engine spinning and let go of the key, often times it would catch and run.

[outofthenorm]

Check the continuity of the plug wires. Could be an internal break that's "hit and miss".

Also, the white on the points isn't necessarily good - I'd run a points file over the surface, especially if it's a new set.

- Norm

[TerryLL]

could it still be the condenser?

Yes. Easy enough to check. Simply disconnect the condenser and check again for spark. The function of the condenser (capacitor) is to filter out high frequency radiation from the points, which can be heard on the AM radio bands.

You can check the ignition switch by bypassing the primary circuit. Connect a jumper wire (16 gauge) from the pos terminal of the battery to he battery side of the coil. Crank the engine with the key. If the engine starts and runs normally the ignition switch is the likely problem. Do not run the engine with this latch-up for any length of time.

[tchiffriller]

Check the continuity of the plug wires. Could be an internal break that's "hit and miss".

Also, the white on the points isn't necessarily good - I'd run a points file over the surface, especially if it's a new set.

- Norm

but there was a fat spark and then no spark so the points must be somewhat good.
But the plug wires are brand new. could that still be a problem?

thats a good idea about linking the battery directly to the coil. unfortunately i cant get to the boat till next sunday but ill find out then!

[TerryLL]

but there was a fat spark and then no spark so the points must be somewhat good.
But the plug wires are brand new. could that still be a problem?

thats a good idea about linking the battery directly to the coil. unfortunately i cant get to the boat till next sunday but ill find out then!

Not likely to be anything you already replaced, and not likely that all the spark plug wires are bad. That center post on the inside of the distributor cap is critical, as is the contact on the top of the rotor. Make sure they are clean and making good contact. I would recommend a new cap and rotor.

Do you have a voltmeter? With the key on you should read 12v at the battery side of the coil with the points open and zero with the points closed. If no meter, then watch the point gap as you turn over the engine and look for slight sparking. Sparking indicates power to the points. If you have power at the points then the likely culprits are rotor, cap, coil, or the wire from the coil to the cap center tower.

[Tom Robb]

Does anyone remember the circumstances of the failure?
High revs - thrown into reverse....
Has he taken the distr. cap off and turned the motor over w/ the starter?
Did the rotor rotate?

[John B]

My bet is timing chain or a stripped cam gear.

[outofthenorm]

One thing no-one has mentioned is to check for gas flow to the carb. Is it getting any? It doesn't take much dirt to bung it up and the occassion might have stirred things up, either in the tank or in the bowl.

Does anyone remember the circumstances of the failure?
High revs - thrown into reverse....
Has he taken the distr. cap off and turned the motor over w/ the starter?
Did the rotor rotate?

Well, suddenly throwing the transmission into reverse should have absolutely no affect on the ignition ... the engine doesn't care what direction the prop is turning. But the engine cutting out at that moment could be very bad, because the high revving might have damaged something. These motors don't like to rev much - above 3000 or so RPM is dangerous territory. Or the sudden stress and vibration could have loosened something - like the bolt that holds the distributor housing. Even a one-eighth turn and the timing could be screwed.

On the other hand, the spark problem has been seen, if not diagnosed. This could also be just an inconvenient, coincidental, intermittent ignition problem ... an electrics issue. If everything else is in good shape, the engine should start even with a dead cylinder. But if there's any other issue - even one that wouldn't normally be a problem - it likely won't start on 3.

Also, just because a part is new doesn't mean it's any good. They likely came from China, donchaknow.

So, be thorough. Test each plug like you did the #1. You'll either get spark at each cylinder or not. If one wire doesn't spark and the others do, you've likely got your culprit. If something else happens, but it still won't start , use a meter to check continuity in the wire from the coil to the distributor - that's where the internal breaK could be. If still no luck, clean the points as I suggested (it takes 3 seconds). For points, "somewhat good" isn't good enough.

The other smart thing to do is to replace the points and condenser with a Pertronix ignition kit and a stronger coil. Works a charm.

BTW, this isn't guesswork on my part, it's just part of a practical trouble-shooting routine that has brought me home many a day.

[TerryLL]

Does anyone remember the circumstances of the failure?
High revs - thrown into reverse....
Has he taken the distr. cap off and turned the motor over w/ the starter?
Did the rotor rotate?

Critical questions that have been asked but not answered. Hard to troubleshoot without some feedback. I'm going on the assumption that the engine is intact and operating properly, but the spark is absent. That assumption might be completely wrong.

[Canoeyawl]

A defective condenser will allow a spark once then, no more...

[sdowney717]

points were nice and white

What you need to check is if the points are making good electrical contact. One thing is to check the continuity with an ohm meter.
The other is with the points closed, current should be flowing to the coil. when the points open, the coil primary field collapses and this induces the secondary windings to spark.
You can open the points when they are shut and you should get a spark with the ignition on.

[Michael D. Storey]

This is a simple-minded engine, with ignition technology from the 1920's. Suggest this:
1. Take off the cap, line the engine up on the mark by the flywheel, and see if the timing is good.
2. Turn on the ignition and open the points with a screw driver. Look for a spark at the points. Hold the coil wire near the block and look for spark at the coil. Check leads to the coil and back. Check to see that where the wire enters the distributor, there is not a ground.
3. Crank the engine with the cap off and make sure that the rotor turns.
If you have a good spark at the points, a good spark at the coil, reasonably good timing (the engine will fire with only static timing checked), put the rotor on, put the cap on, make sure that the wires are properly plugged into the proper plug.
Assuming that the plug wires are good you will now get enough of a jolt to make a spark, assuming that you have not wet your plugs up real good with all of that cranking.
It is a simple engine. I strongly urge you to dope this out on your own with advice found here, because the engine will never fail at dockside. I have a slant that you would be as well served to be as expert in enginery as you are at sailing, if you depend on each equally.
Jusayin.

[TerryLL]

It is a simple engine. I strongly urge you to dope this out on your own with advice found here, because the engine will never fail at dockside. I have a slant that you would be as well served to be as expert in enginery as you are at sailing, if you depend on each equally.
Jusayin.

That's about the best advice offered so far.

[tchiffriller]

2. Turn on the ignition and open the points with a screw driver. Look for a spark at the points. Hold the coil wire near the block and look for spark at the coil. Check leads to the coil and back. Check to see that where the wire enters the distributor, there is not a ground.

There is a ground. what does that mean?

And the engine does run fine it cranks well and i cant think it would be the points because at one point i was having such a constant meaty spark and now im not.

the point rotor does rotate too

[Michael D. Storey]

There is a ground. what does that mean?

And the engine does run fine it cranks well and i cant think it would be the points because at one point i was having such a constant meaty spark and now im not.

the point rotor does rotate too

There is a wire that runs from the points to the coil. When the points are closed, power flows thru the wire and is grounded out by the points. When they open, the power jumps in the coil and makes the 6ooo volt spark. Dont axe me how. Well, if that wire has worn insulation where it goes thru the distributor housing and grounds out there, the points will never effect the electricity flow, and there will never be a spark. Check the continuity of the wire. NAPA will sell a wire with an alligator clip on one end and a light on an ice pick on the other. Clip it on to the wire where it enters the distributor. Stick the other end onto a ground, say, your battery. If things are functioning properly, when the points open, the light will go on. If not, there is a break in the wire or at the points, which provides a permanent ground.

[TerryLL]

Here's the circuitry you're dealing with. It is just about the simplest ignition circuit you are ever likely to find.




The circuit is in two parts, the low voltage (12v) primary side, and the high voltage secondary side.

The primary side consists of the battery, the ignition switch, the coil primary, the condenser, and the points. All the wiring on the primary side is small diameter.

The secondary side consists of the coil secondary, the cap, the rotor, and the plugs, and the large diameter secondary wires (plug wires).

Since you changed the coil, I must ask you if the coil is firmly bolted down to the engine? This is required to ground the coil. Did you get the small wires connected to the right terminals?

To troubleshoot, start with the primary circuit. With the ingnition switch on, you should get faint sparking at the points when they open and close. Do you have sparking? If yes then the primary side is not the problem. If no sparking, disconnect the condenser and try again. If still no sparking, bypass the ignition switch with a jumper from battery+ to coil+, try again. If still no sparking the likely suspect is a bad wire or a missing ground.

For the secondary circuit, first make sure the coil case is grounded. The contacts in the coil tower and the cap towers should be clean and the spark plug wires must be fully inserted. Did you get all the wires in the right holes when you changed the wires? Did you change the wire that goes into the coil? Check the center contact inside the cap that connects to the rotor. It should be clean and bright. The rotor end and the spark plug terminals inside the cap should be clean and bright. Did you put on a new cap? New rotor? Troubleshooting the secondary circuit is mostly a visual check. If all the terminals are clean and bright and all the connections are solid, and the coil is good, it will produce spark. At this point I must ask you how exactly are you testing for spark?

A continuity tester has been mentioned. It is quite easy to get false and misleading readings using a continuity tester unless the wire you are testing is completely removed from the rest of the circuitry. If you don't know how to use a continuity tester, or a static test light, or a voltmeter, get a book on basic 12v marine circuitry and read it.