Cranks but no start

Sounds like a problem in the distributor. Take the wire from the distributor off the
coil, stick a piece of paper between the points then put the probe of your test light
on the wire from the distributor(alligator clip still on the battery -) if it lights you have a short in the distributor.
 
Luke, You need to get your head around this POS ground system. The POSITIVE battery terminal is connected to the chassis, body, ground RETURN for the whole electrical system. The NEGATIVE battery terminal is the insulated POWER SUPPLY for all electrical components in your car. When testing for POWER on an electrical component with your test light the alligator clip on the wire goes to a good ground on the engine block or the chassis or the body metal. The test light probe goes to the power supply terminal on the component you are testing to see if it has power. You have been connecting your test light incorrectly. The negative terminal on the ignition coil connects to the ignition switch output supply when the key is ON. The POSITIVE marked terminal on the coil connects to the distributer contacts which ground the coil when the contacts are closed ONLY. To test to see if the distributer contacts are working correctly do this test. Connect the alligator clip of your test light to the coil POSITIVE terminal. Connect the probe of your test light to the coil NEGATIVE terminal. Turn ignition key ON and test light will only light up if the distributer contacts are CLOSED. Press starter button and crank engine over which should cause the test light to flash ON and OFF as the distributer contacts close and open. If the test light is not flashing when engine is cranked then there is a possible problem with the dist contacts not grounding the coil primary circuit. All your 3 ignition coils are probably OK. Get back to us. Regards, Kevin.
 
So I put the clip on the + coil side and the probe on the - coil side with key on and it is lit up. When I crank the engine it just stays lit, no flashing on and off
 
53_mercLuke said:
So I put the clip on the + coil side and the probe on the - coil side with key on and it is lit up. When I crank the engine it just stays lit, no flashing on and off
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Well there you go, the points are not working. They are either not opening/closing (always staying closed) or shorted to ground. The short to ground is the most likely issue. As suggested above, try putting paper or something between the points to insulate them and see if it still lights up. If it does there is a short.
 
JSeery said:
Well there you go, the points are not working. They are either not opening/closing (always staying closed) or shorted to ground. The short to ground is the most likely issue. As suggested above, try putting paper or something between the points to insulate them and see if it still lights up. If it does there is a short.
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I put a piece of paper in just now and if I have the clip on the - side of the battery it lights up, if I have it on the positive side of the battery it doesn't? So if it's positive ground do I hook the clip to the test light to the positive side of the battery?
 
53_mercLuke said:
I put a piece of paper in just now and if I have the clip on the - side of the battery it lights up, if I have it on the positive side of the battery it doesn't? So if it's positive ground do I hook the clip to the test light to the positive side of the battery?
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I'm getting lost at what you are doing now. Are we talking continuity tester or voltage tester here? What happened to the test between the (+) side of the coil and the (-) side of the coil?

You seem to be getting confused about what is going on here. If you are checking from the points themselves to the (-) battery post that would be a path for current to flow from the battery to ground and would indicate a short, and yes would most likely be the wires inside the distributor. When you start checking from the points to the (+) post on the battery that's when you lose me. Why would you check from ground to ground? There is no current source involved and nothing to really check there????
 
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Well that's were I get confused, if I hook my test light up to the - battery terminal and touch the probe to the wire off the bottom distributor with a piece of paper in the points the test light lights up. But if I take a test light and put it to a spark plug in the head, the test light also lights up. This is where I get confused, because if I unhook the wire from the distributor to the + side of coil as long as the distributor is in the block I have power to that wire with my test light hooked to the - battery terminal.
 
long as the distributor is in the block I have power to that wire with my test light hooked to the - battery terminal.

You don't have power to that wire you have a short or path to ground.
It sounds like the wire or points are grounded.
 
Luke, can you take several nice clear (sharp) close up photos of the inside of the distributer. Something seems to be wrong in there. I guess you have set the points gap correctly by making sure the fibre rubbing block is resting on the lobe (high spot) of the cam when you set the gap. If there is a ground wire inside the dist it could have been connected on to the points terminal instead of the baseplate. Regards, Kevin.
 
I did replace the 2 wires inside earlier today, I am gonna tear it completely apart and clean everything up better
 

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Some basic questions:

With the distributor in the block, does the rotor turn when you crank the engine?

Have you set the gap correctly?

With the distributor out of the engine, use an ohm meter to measure resistance between the terminal where the wire from the coil connects and the metal case of the distributor.

Then turn the rotor by hand until the cam follower is on a flat of the cam. The ohm meter should read very close to 0 ohms.

Then turn the rotor by hand until the cam follower is on a high point of the cam. The ohm meter should now read infinity (open circuit).

I once had a distributor that had an internal partial short such that the last test read about 1000 ohms rather than infinity. That was a definite no start.
 
47COE said:
Some basic questions:

With the distributor in the block, does the rotor turn when you crank the engine?

Have you set the gap correctly?

With the distributor out of the engine, use an ohm meter to measure resistance between the terminal where the wire from the coil connects and the metal case of the distributor.

Then turn the rotor by hand until the cam follower is on a flat of the cam. The ohm meter should read very close to 0 ohms.

Then turn the rotor by hand until the cam follower is on a high point of the cam. The ohm meter should now read infinity (open circuit).

I once had a distributor that had an internal partial short such that the last test read about 1000 ohms rather than infinity. That was a definite no start.
Click to expand...

The rotor does turn when I crank the engine and I set the point gap at .015" . I will try the ohm reading and see what happens
 
A verry simple and basic test for spark at the points, and one that I use, is just to remove the dist cap and with the ignition switch on and points closed, short them out with a screw driver. If all is well you will see a spark. If no spark, then there is a break in the circuit somewhere back to the coil. I had to replace the wire from coil to distributor on my 52 as the old insulation was bared enough to short out intermittently.
 
I would try hot wiring from the battery- to the - post on the coil then try to start it. If it starts the problem is in the wiring, if it doesn't start the problem is in the ignition system.
 
Wow Luke you have been blessed with a ton of great info we can all use. I know you will get it worked out. Don't get discouraged, and thanks for opening this subject so we can all learn. Love this forum!
 
So I tested the ohms from the wire that hooks up to the coil from the distributor to the distributor case with the distributor out of the vehicle. With the points closed on the flat of the cam I get 000.1 ohms and with the points open on high part of cam I get 000.0 ohms. I tried to short the points with a screwdriver driver and nothing happened. I checked the wires in the distributor for bare wire or anything and can't find anything wrong.
 

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With the ohm meter connected to the distributor wire on one lead and the other lead grounded to the distributor housing, there should be a reading of 1 with the points open. It sounds like the distributor is shorted internally.
 
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