no spark from cap

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vaz316

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I have a slant 6 in my 68 Dart and plan to keep it. I will get the pertronix II for it soon but at the present time I cant afford to and it does have a brand new cap, rotor, condensor, and points as well as plugs and the wires are like new. I get spark from the coil but nothing from to the plugs. The motor ran for about 5 minutes one day but the idle was way too high and as I was adjusting it the motor died and hasnt fired since. It has been 30+ years since I adjusted points but I think I still did it correctly get the high point and then I set the gap at .020. Any info is appreciated and yes the carb has been rebuilt and I am getting gas no prob so its just spark preventing it from firing.


Thank you in advance
Vaz
 
re check the point gap, it may have slipped, if you have spark from the coil, then it has to be in the distributor.
 
Set the points with a dwell meter. You could have had the feeler gauge in at an angle. Also, make sure you have the proper lock washers on the screw securing the points to the breaker plate, or they WILL work loose.
 
If the idle was way too high, and the carb was previously fine, it might be that the ignition timing is advanced too much.
 
YOU GET SPARK from the coil?

How long? Blue? Red? snappy? weak?

If you get a good spark from the coil, FORGET the points and condenser for now

RECHECK the spark at the coil

Do this TWO ways, in order to check the coil wire

1 Devise a grounded probe, IE screwdriver and clip lead, or even a spare spark plug that you can "rig" for a gap. Hold the probe into the top of the coil tower and look for the quality of the spark. Most healty systems will jumper a spark with the probe held clear to the top of the coil tower.

You MUST use the key to crank the engine (instead of jumpering the start relay) because of the ballast bypass circuit OR you can "cheat................................."...............

To be able to crank the engine by jumpering the relay, which is obviously handier if you are alone, do one of two things-----either jumper the ballast with a clip lead, or hook a clip lead to the coil + terminal and to battery. A handy way to do that is from the coil + to the alternator output stud. Do NOT leave this hooked up any longer than for testing.

So the FIRST QUESTION after this test is

A Is the spark out of the coil OK?

B Is the spark weak?

A If OK, add the coil wire, and check the spark again at the end of the coil wire. Hey, coil wires go bad. If that looks OK, then Take a GOOD look at the cap, the rotor, for grease, dirt, moisture, cracks, carbon tracks, or physical damage, and pay attention, "was the cap seated properly" in the "key" on the distributor?

IF that seems OK, then test spark AT the cap at one or two different plug wire towers, using the same method as with the coil, IE a grounded probe held near/ into the top of the tower

B IF the spark is weak, then it's power supply, coil, points, condenser

So again, to make SURE you have power, jumper a clip from the coi + to the battery or alternator output stud, and check spark right at the coil

IF it is weak, it's either points, condenser, or coil.

Points and condenser are cheapest. Even if points are gapped correctly, they can be damaged, misaligned, and otherwise not making good contact.

You MUST have a good condenser. Condensers are NOT only to "keep points from burning." Condensers help form the spark, and MUST be good

The coil. This is a crap shoot. If you have a known good spare, does not take long to substitute. Yo do NOT need to even mount a spare coil, or even ground it!!! You can just "lay" it down there somewhere and hook it up!!!!
 
I used the coil wire to test the spark yesterday. As my helper turned the starter over I put the cap end of the coil wire near a good ground and when he turned the key it sparked immediately. Looked to be a good spark it was orange yellow in color. I didnt remove the distributor to set the points but maybe I should. the condensor is new as are the points but i have read where some have bad condensors right out of the box and they did come from autozone lol.....Ill keep you guys posted on my progress and try to upload a pic of the Dart. Thanks to everyone for their responses
 
Badsport said:
A good spark should be blue and have a resounding snap to it.
Click to expand...

Resistor wires can fool ya. That's why I ALWAYS tell you guys to check with a grounded clip lead and probe, right at the coil tower.
 
thanks everyone I got her fired up this am but she isnt charging the battery so off to check on a new alternator and recharge the battery. She ran awsome so I think there are many more miles on the old girl. Thanks again for the imput. What actually happened was when I changed the cap I used the breather on the old cap to attach the wires but the new cheap cap from the zone had the breather on the opposite side of the cap so all the wires were in the wrong position. This time I actually removed the distributor to make sure the points were gapped correctly and everything was tight and the nylon gear was in excellent shape then with number one at tdc I lined her all up and had my cousin turn her over while I checked number one for spark it had it but weak so we jumped her off of my van and she fired up after a few pumps and ran nice but then died after a minute or so and when I tried to fire her back up no very little juice so im taking the zone back there yellow top pos getting a new one (free of course) and I will replace the alternator later I think I have several from other projects. Thanks again to all who responded

Vaz
 
With respect, it doesn't sound to me like you actually fixed the problem

What I mean is, the object of a tune-up is not to get the engine to run, especially with the help of jumper cables if that's what I understood. The object of a tuneup is to get the engine in "running tune" to replace bad parts, and to find any problems that are undermining what might well be "start at the touch of the key."
 
you are correct it runs awsome now it was mostly a timing issue. In addition I had to replace the alternator it was not charging properly and installed a new battery all is fine now back to the paint and interior trying for september car show in johnston RI its my favorite in my area
 
It was at a city park a toy run by the marines I think but it was awsome we all just take over the park and like 500 cars are parked everywhere. Ill have to look it up for this year not sure if it was a reschedule from a rain date last year but it was near the end of september last year. I met up with a group at tractor supply in jewett city then we drove up 395 to route 6 stopped for breakfast at a diner on the way and I followed the others to the park in Johnston. Ill look it up and let you know this years date
 
Come join RISRA and the USMC for the

36th Annual




Toys for Tots Fun Run



Celebrate Columbus Day
Sunday, Oct 7, 2012


at



Johnston War Memorial Park
1583 Hartford Ave
Route 6, Johnston,RI




Registration Fee ; "Toy for a Tot"
(1 new unwrapped toy)
"Food for the Needy"
(1 can of food)
Registration Time Starts at 9:00 am




All Cars Welcome
 
you are given food coupons when you register and its a fun day in an awsome setting hope to see you there ill have pics posted of my dart by then so come and find me if you show up
 
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