I tried to get my new engine going for a couple hours tonight and it just cranks, no fire.

Got fuel to the carbs, but no spark at the plugs

Checked the coil and I get 12V off each side to ground, is this correct?

What is next in the diagnosis...what else can I check?

That isn't right... Are you running points?

pos + on the coil should read about 12V. the neg - on the coil should go to the points and to a condensor.

Unplug the black/purple (thinner) wire from the coil. (It should have been on the - terminal, BTW.) Now make sure that the green wire from the points/condensor gets shorted to ground and then disconnected as the distributor rotor turns.

How's the ground braid inside the distributor? The points ground through that.

--DD

If you have the stock system, remove the distributor cap.

Connect one end of a test lamp on the negative (point side) of the coil and the other to ground. Crank the engine and if you get a pulsing light, the points and coil are working.

If the light stays ON or stays OFF during cranking, then the problem is not the coil and you need to look elsewhere- such as the points and condenser.

Put the test lamp across the positive and the negative terminals of the coil. Have somebody crank the engine over, If it pulses, then this means there is 12 v to the + and - terminals, and the points and condenser are working.

Look at the points, if they spark when opening and closing, you probably have a bad condenser.

Put the cap back on. If you still have no spark, then either the coil is bad or one or more of the coil wire and/or spark plug wires are shot.

Hope this helps.

Brett,
besides the comments about wiring...have some one crank the engine and go back and verify the rotor is really turning inside the dizzy and check if the points are opening and closing. While your at it, pull the coil wire and see if your getting spark out of the coil. I know the above is probably a no brainer and you've probably already done this, but a good place to start.

Thanks for the replies...I'll start the process of going through everything tonight, ran out of time last night.

We pulled the cap and the rotor and points looked fine, but I'll double check for spark. We switched out the coil for one I had laying around and still no go.

I'm still waiting for some help to arrive to help with cranking, but in the meantime, I'm still a little confused why I'm getting 12V off both the + AND - side of the coil when the key is in the ON position, shouldn't I only get 12V off the + side?

The short version is you'll only see ground on the - side when the points are closed.

If you turn the engine by hand and you -never- see ground at the 12V side, find out why your points are not closing. You get spark -only- when the points open.

Still coming up with nothing...

I don't have a test lamp, so I just used a multimeter expecting to see a voltage drop. When cranking, I get the same thing off both sides of the coil...the voltage drops from ~12V to ~10.5V and holds there. I pulled the coil wire off the distributor and couldn't see a spark while cranking, but I'm not sure if I should "see" it for sure.

Points are opening and closing and the ground braid looks fine..both the distributor and coil look new, but who knows...

Any ideas?

Unplug the points wire at the distributor. Now check to see if it goes to ground and then gets disconnected when you rotate the engine. It's easier if you rotate it slowly, possibly with the turn-one-wheel-in-5th-gear trick.

Does it get grounded and then disconnected? If not, then the points or the points plate or the ground braid are the problem.

--DD

Thanks Dave...I'll try that tonight

well I got it figured out...thanks to Justin looking closer, he saw there was come corrosion on the points. A little sandpaper and it fired right up!

First time hearing the the engine and my car running in 10 months

I'll update more later:)

That's fantastic...updates please, with pictures.

Hi,
Replace the points. They are plated and once they have pitting, they are pretty much done and will never stay clean.

New points cost $4.00
Go get some....get two sets so you always have a new set on hand.

Rich

Already one step ahead of you Rich... already ordered new cap, rotor, points, etc.

Just excited I have a running car until they show up:)