L-79 engine won't start...

[Patrick T.]

I parked my '67 in the garage 2 years ago to do some work on it. At the time, it ran like a bat outta hell. The only thing I changed was the coil which is a new AC Delco and a new voltage regulator.

Got the car all wired back up and all the electrical accessories work...radio, heater, clock, wipers, horn, headlights, brake lights, hazard flashers and the engine cranks over smoothly, however it doesn't even burp, backfire or anything. The carb is getting gas.

I static timed the engine according to the book and I know it's in the ball park for starting. I hooked up the timing light but am getting no flash when I crank the engine.

I've traced the problem so far is that there is no voltage going to the coil and hence, no spark to the plugs. Tomorrow I going to check the wires down under where they hook up to the starter motor and solenoid, but it seems to me if they were hooked up wrong, nothing else would work and the engine wouldn't crank over.

I running out of clues on this one, how come I'm getting no voltage to the coil? I need some help on this one guys. Thanks for any hints. PT

[Jim T.]

Re: L-79 engine won't start...

Do you have 12 volts going to the ballast resistor?
What is the voltage leaving the ballast resistor immediately when you turn on the key to on?

[William C.]

Re: L-79 engine won't start...

If it will crank, you should have spark due to the bypass circuit from the solenoid to the coil. If no "fire on the wire" the first place to check is for the proper orientation of the terminals on the starter solenoid and the ground at that point. assuming you have checked the distributor for proper point closing/opening, etc. Just a thought, if the dist doesn't fire, how did you time the engine?

[Patrick T.]

Re: L-79 engine won't start...

Thanks for your comments, I will check them out tomorrow. Bill, as I mentioned above, I timed it static (at rest) by lining up the timing marks on the balancer at 10 degrees BTDC and then dropping in the distributor until the rotor was pointing at the #1 firing post. PT

[William C.]

Re: L-79 engine won't start...

Check the starter wiring first, two things, one being forgetting that the large ring terminal is a ground and the other not attaching the bypass wire (Black with yellow stripes or plain yellow depending on year) to the proper stud. Ground on wrong stud can cause smoke and attendent problems....

[Joe C.]

Re: L-79 engine won't start...

Thanks for your comments, I will check them out tomorrow. Bill, as I mentioned above, I timed it static (at rest) by lining up the timing marks on the balancer at 10 degrees BTDC and then dropping in the distributor until the rotor was pointing at the #1 firing post. PT

Patrick,

I'm sure you know that one rotor rotation equals two crankshaft rotations. Was #1 or was #6 cylinder on top of compression stroke? Two ways to check that, with marks lined up:

1. Remove valve cover and see that both valves are closed on cylinder #1.
2. Remove spark plug, and see if cylinder #1 will hold compressed air.

It's very possible that your rotor is 180 degrees out of phase.

Joe

[Mark W.]

Re: L-79 engine won't start...

Does your car have transistorized ignition?

[Jim B.]

Re: L-79 engine won't start...

You haven't mentioned the points and their condition. My 68 L79 has the most problem with the points when not run for a long time. They either close and won't open or they stay open. (which would explain no voltage to the coil)

Suggest you start there. The voltage to the coil should be truning off and on with the points.

I bought a pertronics electronic breaker system set to replace the points when I use the car for fun.

[Terry D.]

Re: L-79 engine won't start...

I'm assuming you have a points and condensor distributor. A bad condensor will do what you describe.
Terry

[Mike M.]

Re: L-79 engine won't start...

Whoa!, hold up here for a minute, Guys.
Back to basics...key words...
Ran fine B4,
Changed Coil & V. R. only,
Everything else works,
NO VOLTAGE TO THE COIL.
Even if 180 off, with spark, it should still crackle, pop, sputter or something.
Hint: Wire, Ground, Connections...
Chew on this for awhile and
Have a Nice Day!

[Mike M.]

Re: L-79 engine won't start...

Patrick,
I degress,
the exact same circumstances occurred with me back in the day.
No Spark, we tried everything, switched the originaland other parts back in, tested, tested and more.
Finally my Buddy went to pull his hand out from under the distributor and snagged his ring on the ground wire, apparently snapping the wire in two.
Upon closer examination, the wire was actually burned, separating the connection by about 1/8", and held together only by the insulation.
If he hadn't of made this little gufaw, we would still be trying to figure out the problem.
HaND