No spark plug spark... 170 MC , 1985 Sea Ray

[glennj3]

unless I personally stabbed the distributor into the side of the motor and made sure a particular tower was aimed for cylinder #1, there is no way for me to ever know how many times the distributor was pulled, or which tower is for cylinder #1

the only true way to know is to pull spark plug #1, rotate around until the motor is at TDC, align the timing marks, then look at which tower the rotor is pointing at.

the other method is to see which wire is currently on cylinder 1, and using a timing light, set timing to that cylinder

what does your timing light show you?

None of my plug wires have any current through them.

 

[Scott Danforth]

None of my plug wires have any current through them.

Huhhh?

they wont have current going thru them, they only will have high voltage when the rotor lines up with the button on the cap as the magnetic field in the coil is collapsing as the points open up.

I highly recommend you do some research on the theory of the otto cycle and how a points type ignition works.

 

[glennj3]

Huhhh?

they wont have current going thru them, they only will have high voltage when the rotor lines up with the button on the cap as the magnetic field in the coil is collapsing as the points open up.

I highly recommend you do some research on the theory of the otto cycle and how a points type ignition works.

That is what I’m referring to. No current at all as the engine turns over.

 

[Scott Danforth]

Ther should never be current. Only 40,000 volts

Why are you looking for current?

 

[nola mike]

I’m typing as I test here now. I just ran a wire from the coil plug connector with the tester in line to the #1 plug. Turned the engine over and it backfired like a gun.
I removed the point and cleaned them with sand paper. Reset them at 022. They look good.
Again, new cap & rotor.
It ran fine when I put her up 3 months ago.

If it backfired then you have spark, probably at the wrong time. I'm guessing your wires aren't in the right place.

 

[glennj3]

That is what I’m referring to. No current at all as the engine turns over.

If it will shock me I call it current! I’m not a mechanic nor an electrician. It’s a matter if terminology

 

[nola mike]

If it will shock me I call it current! I’m not a mechanic nor an electrician. It’s a matter if terminology

And when you use it wrong it's confusing. Current and voltage are measured differently.

 

[glennj3]

If it backfired then you have spark, probably at the wrong time. I'm guessing your wires aren't in the right place.

That’s why I have to ID where # 1 wire is located on the cap. Possibly it’s 180 degrees off. Just don’t understand why it stopped cranking up (running) by sitting still.
I’ll be doing the compression check for locating # 1 position of the rotor today.
I I here a 73 Super Beetle, I replaced the distributor, I know which wire on the rotor goes to # 1 cylinder. I don’t have to check it every time I remove it

 

[Scott Danforth]

if there was any current, you would be dead when it shocks you

points film over when sitting

however you have stated repeatedly that you have spark at the coil. if you have spark at the coil and none at the plugs, its either the cap, rotor, or wires

if you do not have spark at the coil, the use of a dwell meter will tell you if the primary side of the coil is being triggered by the points. if there is no reading on the dwell meter, there is no opening and closing of the ground side of the coil by the points.

you should only have to verify cylinder #1 once, then label it. or use your timing light to see if its flashing near the timing mark.

 

[glennj3]

I’ll check for compression on # 1 TDC & make sure the correct wire is set.
I can’t use my timing light or dwell if the engine is not running or It does not have a spark going to a plug.
Thanks fir helping me!

 

[Scott Danforth]

I’ll check for compression on # 1 TDC & make sure the correct wire is set.
I can’t use my timing light or dwell if the engine is not running or It does not have a spark going to a plug.
Thanks fir helping me!

bullcrap.

you dont even need the distributor cap on to check dwell, you need the dwell meter across the coil terminals and you need to be able to crank the motor. thats how I have been adjusting point gap for nearly 40 years.

timing light while cranking is how I normally set timing on any new build, long before there is fuel in the motor.

 

[glennj3]

I don’t have a dwell meter yet but I removed the plugs & turned to the compression stroke # 1 cylinder. The rotor would be on the # 1 terminal on the cap for the correct wire going to # 1.
the points are closed.
I checked with my ohm meter, should the plate the points are attached to be grounded to the negative on the coil as well as the screws that hold the plate down, the condenser too? Even the distributor shaft that the rotor spins on?

 

[glennj3]

Those are my old timing marks on the flywheel part.

 

[glennj3]

I checked the points with a 12 volt light, the light comes on with the ignition switch on while touching the points while using the negative end of the test light to the points plate or my negative battery. Placing the light tip on the positive terminal of the coil it also light up but is a dim light until I open the points, then the light gets bright.

 

[nola mike]

timing light while cranking is how I normally set timing on any new build, long before there is fuel in the motor.

Not if he doesn't have a spark.
Op, not sure what you're testing there. I *think* what you're doing is essentially checking for 12v at the coil (-), which isn't useful, and will get you those results.

 

[glennj3]

I was just looking for anything wrong. Still have not figured out why I don’t have a spark where it should be! Everything is set where it should be.

 

[glennj3]

So my coil does send a spark down the plug wire to the distributor cap. It also does this if I open the point. I replace the distributor cap and nothing. Still at it.
I just put my timing light on the coil plug wire while turning the engine over my timing light only comes on irregularly.
do I have a bad coil?

 

[glennj3]

To F/U, I found an old coil in my boat. It may or may not be good. I exchanged it out with this old one. Same results. Very intermittent and irregular flash with my timing light.

 

[Scott06]

So my coil does send a spark down the plug wire to the distributor cap. It also does this if I open the point. I replace the distributor cap and nothing. Still at it.
I just put my timing light on the coil plug wire while turning the engine over my timing light only comes on irregularly.
do I have a bad coil?

Do you have the connection from the cap down onto the rotor? May be missing if you have a spark off the coil to ground- good consistent blue spark, then the issue is in cap rotor or plug wires

 

[glennj3]

Do you have the connection from the cap down onto the rotor? May be missing if you have a spark off the coil to ground- good consistent blue spark, then the issue is in cap rotor or plug wires

To clarify, the coil wire sparks with the timing light with the engine turning over very sporadicly, sometimes several engine revolutions with no spark! I replaced the coil with an old one I had and it did the same thing.
Guess I’ll go buy a ew one.