No spark

[Guest]

Hi guys,, I need some advice. I have a 79 Pearson 31 with atomic 4. Motored to slip about 3 months ago and have not used the motor since then. I decided to get it ready for spring,, so I changed the plugs,, rotor, distributer cap and cleaned the points with some sandpaper. I did not start the motor before I changed all the parts. I tried to start,, starter working,, but would not start,, so I cked to see if I had spark at the plug,, no spark,, so then I started reading ,, I then checked to see if I had 12v to the positive side of the coil,, no 12v there either. let me add another detail,, I have to turn the ignition key in the cabin to on,, then hit the starter switch in the cockpit. I checked to see it if I had 12 volts at the igniton switch when the switch is turned on and I do. I was looking at the wiring diagram and see the purple wires,, one goes to the cockpit instrument panel and the other is supposed to go to the ignition switch. on the ignition switch,, I just have two connectors,, all red wires,, so I am thinking that the +12 volts red wire is tied to the two purple wires somewhere in the wiring harness. I also do not see any male/female wiring harness connector that is in the wiring diagram.

I just want to make sure that i am going about tracking the problem correctly or if there is something I am missing like a fuse or something. I find it strange that it was working and not it is not.. I also reverted back to the old parts just to see but no go. I also cked the fuse at the starter and another one that I found and they checked okay.

any suggestions would be appreciated before I start trying to find the connection of the red/purple wires.

thanks
Mark

[ndutton]

It's time to start tracing the wire from the ignition switch (known good point) to the coil (known to be a not so good point), the problem will be found along the way.

When you find the problem, consider the entire harness is of the same age, was made by the same guy and repaired or modified by a previous owner or owners or so-called hired professionals of unknown skills. The ultimate repair is complete replacement.

[ArtJ]

Hi Mark

How are you checking for 12V at the coil? Are you using a voltmeter?

Have you checked at the battery to be sure you have +12 V there first?

Don Moyer always recommends checking the Spark from the center terminal
of the coil to the block or a ground point first because it is much easier
to check the spark there since it will be larger.

You can temporarily remove the wire(s) connected to the Plus side of the coil
and run a jumper wire from the Battery or the Battery terminal on starter
to eliminate a bad connection in the primary ignition circuit or fuse blown. I suggest removing the
wires on the plus coil side first in case you have a short.
There have also been cases of ignition switches or connections to them going bad.

Which reminds me. Double check the wiring and connections inside the
distributor to make sure nothing is accidentally shorting out, including
open or pinched wires entering/ leaving the distributor.

Different topic, you haven't mentioned priming the fuel system.
Of course, you need to fix the +12 volts to the coil first.

Best Regards

Art

[mharal]

no spark

Hi Art,,

I am using a voltmeter to ck for 12v at the coil,, I also did ck for spark from the wire coming from the coil--no spark. I also ran a wire from the battery to the + side of the coil to ck and still no spark,, however I did not remove the other wires,, so I will try that. I am really thinking something may be shorted somewhere in the circuit now. I also think the ignition switch is okay,, since it reads shorted and open when operating and I do get the 12 volts through it when testing.

I will let you know what I find after testing the coil again with all the other wires on the positve terminal removed.

thx for the suggestions
Mark

[Marian Claire]

Any way that the switch could have been left on and fried the coil? Dan S/V Marian Claire

[ArtJ]

Hi Art,,

I am using a voltmeter to ck for 12v at the coil,, I also did ck for spark from the wire coming from the coil--no spark. I also ran a wire from the battery to the + side of the coil to ck and still no spark,, however I did not remove the other wires,, so I will try that. I am really thinking something may be shorted somewhere in the circuit now. I also think the ignition switch is okay,, since it reads shorted and open when operating and I do get the 12 volts through it when testing.

I will let you know what I find after testing the coil again with all the other wires on the positve terminal removed.

thx for the suggestions
Mark

Mark I would double check that nothing you replaced inside the distributor
is shorted or touching something also it must have a good capacitor in the circuit.
The spark is generated by the collapse of the field energy in the coil when
is is grounded switched thru the points.

[mharal]

If the coil was bad,, should I not still get 12v at the positive terminal on the coil?

[mharal]

I will also ck the inside stuff on the distributor cap,, I did not replace the points,, just the rotor and the cap.. but will ck-

[edwardc]

Mark,

Where are you located? Perhaps an nearby Afourian can help.

[mharal]

I am located in Austin, TX,, the boat is on Lake Travis at Paridise Cove Marina.

thx
Mark

[Newenglandah]

If the coil was bad you would still be getting power to it on the positive side if the ignition was on. You could double check the ground off the distributor, you should get an intermitent ground when you rotate the engine. I think its probably that old switch in your cockpit. I have a Pearson 33 and that button went bad on me last fall, I recently rewired and got rid of the starter button for a 4 way ignition in the cockpit, it makes it easier to sail solo when you can kill the motor from the wheel anyway

[Dave Neptune]

Steel it baby!

mharal, did you ar could you try to "hot wire" her. You could have a bit of KRAP stuck on the points and if it insulates ~~ no spark. If the "Hot Wire" gets you spark you can be sure you have a bad connection.
Look alon the path of the wire in the harness for an inline fuse not on the panel~~quite common on re-wire work.
Also if you have an electric pump check the OP-saftey switch for proper operation and or try a jumper wire on it to see if "it" is where the problem is.

Dave Neptune

[JOHN COOKSON]

Let's Get Spark Now!

My approach would be to divide and conquer.

Take all the wires off both coil terminals. Use your ohm meter to see if there is a closed circut from the end of the wire on the -terminal to the distributor breaker plate when the points are closed. Possible problems: Point not conducting or bad wiring.
Check with the ohm meter to see if the same circut is open when the points are open. Possible problems: Bad condenser, bad points, or a short to ground in the wiring.

Test the coil for reistance. There should be ~4 ohms between + and - terminals. Hook the wire back up to the - coil terminal and connect a jumper wire from a hot source to coil+. The big battery terminal on the starter works well. Don't leave this wire connected and hot for more than ~a minute when the engine isn't running or you will risk burning out the coil. Use your volt meter to see if power is getting through the coil to the points. Put the big wire into the center of the coil and hold it near ground (the engine). Flick the points open and let them snap closed. There should be a spark. Possible problem: Shot coil.

Put the distributor cap back on and connect the wires that go with it. Hold a screw driver in a spark plug boot near a plug and check for an arc while you turn the engine over with the starter. Possible problems: Bad distributor cap, bad rotor, bad wiring.

You can use a jumper wire and an ohm meter to check the circut from the key or switch to the coil. If necessary you can run with temporary jumper wire from the switch or key to the coil.

TRUE GRIT

[mharal]

okay, I made a quick stop by the boat this afternoon and removed all the wires from the positive and negative terminals. Measured resistance was zero across the terminals,, a direct short,, pretty sure that means the coil is toast. do you concur? Do i just need to get an new coil and try it or should i take other measures before installing and trying the new coil?

thanks to everyone for all the suggestions,, very helpful,

Mark

[Dave Neptune]

A sure sign!

Mark, a short would certainly kill it! Often a short in a coil will open and close with a bit of temp fluctuation and sometimes aeven a jolt can open or close the short so double check it.
A coil is cheap and it is not a bad idea to have a spare aboard. You could even borrow one to try but the beer bill for borrowing may cost you more.
Be sure to get a coil to suit your ignition either stock (8v), modified stock(12v) or EI.
Does your coil bracket still have a ballast on it? I have seen the stock 8v coils fail when people have eliminated the ballast and not replaced the coil.

Dave Neptune