Can't get it to start

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Paul Herder

Paul Herder

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Nanaimo British Columbia
Hey, I am new to the a body world and their electrical systems. I have a 72 swinger with a 225 slant 6. I currently can't get it to fire. I am not familiar with the points ignition system whatsoever. I have replaced everything from the cap and rotor, to the wires plugs and ballast. I have replaced the coil as well. It still will not start. Is there anyone in here from the Nanaimo b.c. area that could give me a hand??

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I am not in BC, but have you been through the basics?

Does it have fire out of the coil when cranked? If not:

Do you have 12v to the ballast and ~9v to the positive (+) side of the coil? Is the wire from the points intact (cannot be grounded) and connected to the negative (-) side of the coil? Do you have about .017" gap on the points?

If you can check off all those, then it should have fire. Now it is just a matter of getting it at the right time, but that is for another post.

sb
 
mopar_nocar said:
I am not in BC, but have you been through the basics?

Does it have fire out of the coil when cranked? If not:

Do you have 12v to the ballast and ~9v to the positive (+) side of the coil? Is the wire from the points intact (cannot be grounded) and connected to the negative (-) side of the coil? Do you have about .017" gap on the points?

If you can check off all those, then it should have fire. Now it is just a matter of getting it at the right time, but that is for another post.

sb
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Yes i get a bright blue spark out of the coil. So I'm getting spark. It just won't run. And i cant figure out why. Last thing I can think of is the points and I don't know how to begin checking it. I'm new in the points game but have a pretty.good mechanical knowledge.
 
Paul Herder said:
Yes i get a bright blue spark out of the coil. So I'm getting spark. It just won't run. And i cant figure out why. Last thing I can think of is the points and I don't know how to begin checking it. I'm new in the points game but have a pretty.good mechanical knowledge.

It has a resistor on the side of the coil that is attached to the coil + side and the negative side has the ballast wire and points wire attached.
Click to expand...
 
For starters, make sure your ballist resistor (the white ceramic thing on the fire wall between brake booster and hood hinge) is good, there will be a voltage drop across it with ignition on. Go to your distributor, recheck gap on the points, need feeler gauges for this, OR in a pinch use a match book cover. Rotate crank till rubbing block of points are on a high point of the points cam, loosen the screw (but don't take it out) that holds the points down adjust the gap to .025 inches(using feeler gauge) or the match book cover, in eather case there should be a slight drag as you pull gauge/match book thru the gap, tighten screw, recheck gap. Rotate crank till it is on top dead center, with cap off and rotor on, rotor should be just to the right of cap mounting clip, if not, rotate crank 1 turn, rotor should now be just to the right of the clip. Put the cap back on and reconnect the wires to the cap, firing order is: 1, 5, 3, 8, 2, 4, the rotor spins clock wise.

This should get you started.
 
JBurch said:
For starters, make sure your ballist resistor (the white ceramic thing on the fire wall between brake booster and hood hinge) is good, there will be a voltage drop across it with ignition on. Go to your distributor, recheck gap on the points, need feeler gauges for this, OR in a pinch use a match book cover. Rotate crank till rubbing block of points are on a high point of the points cam, loosen the screw (but don't take it out) that holds the points down adjust the gap to .025 inches(using feeler gauge) or the match book cover, in eather case there should be a slight drag as you pull gauge/match book thru the gap, tighten screw, recheck gap. Rotate crank till it is on top dead center, with cap off and rotor on, rotor should be just to the right of cap mounting clip, if not, rotate crank 1 turn, rotor should now be just to the right of the clip. Put the cap back on and reconnect the wires to the cap, firing order is: 1, 5, 3, 8, 2, 4, the rotor spins clock wise.

This should get you started.
Click to expand...
I will do all of that tonight!!! I haven't done this type of stuff in probably 12 years or so.
 
Ok, if you have fire out of the coil, then the points and condenser are functioning enough that it should run.

Now, it is EASY to turn a slant by hand. Take the cap off, rotate the engine until the timing mark on the crank comes up to timing tab. Now, you have a 50-50 chance that is the correct mark for #1. Check the rotor...it should be pointing to the area of the distributor where the #1 wire connects. Firing order for a slant is 1-5-3-6-2-4 in a clockwise rotation. If any of that is off, fix it. If it is right (and you have fuel) it should fire right up. Assuming the rotor and cap are functional...
 
Next thought..............you do have fuel, right?? All the spark in the world can't do a thing with out gas..........
 
I you have convinced yourself that you have a decent spark "in cranking" there is no sense messing with points, condenser, coil

If you used the coil wire to check spark then THAT is OK

Have you taken a good look at the plugs? oiled/ wet/ dry?

What do you have for fuel? Any chance it is stale? How long has it been in the tank. And How do you KNOW you have fuel?

How about compression, have you run a compression check?
 
Even more basic....the driven gear on the end of the distributor shaft is plastic. Probably 46 year old nylon. With the cap removed, confirm that the rotor turns while the engine is cranked.
 
I fought a RM50 suzuki motor for days: fuel, spark, compression.....uh, compression? Yes, compression ! Msd won't light off a cylinder with no compression. My ring was bad but im sure yours are good enough. Make sure distributor is rotating while cranking use thumb over #1 plug hole to find compression stroke (can turn crank with belts) and you can use a piece of coat hanger in the cylinder to determine TDC on that stroke by observing the wire reach its highest point. Thay will get you very close to tdc. Now look at the rotor direction and the plug wire positions you should be pointing at 1, if not make it so. Does your balancer show you at or close to TDC? At about 10 BTDC, you should be able to pull #1 spark plug and wire and lay attached plug on a grounded surface like the alternator. Turn ignition to run and Loosen distributor hold down and gently turn distributor back and forth to try and get breaker points to just open causing the coil to fire the plug, if everything is close you will observe a spark at plug with very little back and forth movement. That will be close enough to get it to fire. Even a little gas dribbled into the carb will cause a slight start condition. New plugs at about $9, not a bad investment, points are cheaper.
 
Dont get sidetracked!!!

You need compression........enough to run the engine
You need fuel.......FRESH fuel and not diesel or JP-something
You need spark......enough of it and at the right time

You seem to think you have spark. Don't get sidetracked with the distributor drive gear. If you have spark, then and it's decent, then it should either fire or at least cough or backfire

1....What do you have for compression? Might be time to run a compression check/ leakdown

2....Could the cam timing be off? There's a procedure in the shop manual to find out

3....Fuel......Has the car been parked, sitting and could the fuel be stale or contaminated?

=============================

What led up to this? Has it been parked / stored? Did it quit one day? Had it been running until you decided to tune it up?
 
I'm curious at what point it wouldn't start

But, the OP hasn't said a peep for a week so it's possible he's out driving it right now...
 
I glanced at this quickly. I did not see where you changed to fresh points, condenser, set gap @ .017, yes that plastic gear at end of dist needs to be replaced, They are cheap off feebay or where ever.
If compression is low, I have poured engine oil down carb, turned it over enough to get into cylinders, prime carb with gas, should start if getting fire. Compression on engine that has been sitting a long time, and pretty wore out, ... got have enough for it to start and run.
If it starts and does not stay running, replace ballast.
 
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