1961 Cadillac cranks but won't start what am I missing?

[Matt Innocenzi]

Hello all,

I have a 1961 Cadillac Sedan DeVille I am trying to restore.  The generator light came on after I changed the battery so I wanted to polarize the system to make sure that was not the problem.  I connected a jumper wire between armature and battery terminals on the voltage regulator.  Unlike other times I had done this, I got a very tiny spark and heard a click in the voltage regulator.  Strangely, the GEN light illuminated in the dash without the keys even being installed.  Very strange.

Stranger still, I went to start it, and it just cranked over and over without starting.  I have fuel and I have spark.  Even with ether, it will just crank over and over.  Occasionally, it will spin faster as if it is going to catch, but nothing.

I checked the floats on the carb and they were within spec.  Changed the points for the heck of it, and still nothing.

Could the polarizing have done something weird or just coincidence?

Any thoughts or suggestions?

Thanks in advance,
Matt

[Scot Minesinger]

That sound the voltage regulator made could be a failure (happened to me once).  Then when starter spins faster, it could be because it is receiving a higher unregulated voltage as result of generator and battery.  However, car should still start I think.  I know this is not your first rodeo. 

Could the coil be faulty providing spark but not high enough voltage to jump the spark plug gap inside the engine?  Replace the condenser, that little bugger is often the culprit.  I know people who replaced timing chains when it was the condenser.  Betting on condenser.

Did the car run before you started work, or was the engine apart (distributor 180' out?).

[Jon S]

I have changed many batteries in my 1958 and have never polarized the generator; nor for that matter, never heard of this process. What is the purpose?  Whenever I've changed my battery, the car starts right up and runs just fine. Never saw anything in the Shop Manual about the need to polarize anything when replacing a battery.

[Bobby B]

I have changed many batteries in my 1958 and have never polarized the generator; nor for that matter, never heard of this process. What is the purpose?  Whenever I've changed my battery, the car starts right up and runs just fine. Never saw anything in the Dhop Manual sbout the need to polarize anything when replacing a battery.

Jon,
Polarization is a procedure which matches the polarity for the generator and the voltage regulator by permitting a surge of current to flow through the generator, correctly polarizing it. Damage to electrical components can occur if polarities do not match.  The polarity of the generator must be set to match that of the voltage regulator.

Polarization of the generator should take place whenever the Battery, Generator, or Regulator are replaced or serviced.
                                      Bobby

[Dan LeBlanc]

Jon, it's most definitely in the 61 Shop Manual.  Momentarily touch a jumper wire between GEN and BAT on the voltage regulator terminals.

[Smedly]

I would take one of the plug wires off ( At the plug end) and attach to spare plug. rest the plug so it is grounded to the motor and have someone crank the engine over. watch the plug to see if it is sparking.
What are the chances it is flooded. I have had engines flooded to the point ether wont help, I had to take all plugs out and blow compressed air into cylinders to dry them out then add a little oil in each before cranking any more.

[Dan LeBlanc]

Systematic troubleshooting of no spark:

Step by Step Diagnosis (trouble shooting):

Spark voltages are normally 5,000 volts to 15,000 volts and can be 40,000 volts.

Before beginning, make sure the coil wire and spark plug wires are dry and in good condition.

1) Disconnect both sides of the coil (+) and (-)

2) Check primary resistance of the coil from the (+) to the (-). Resistance should fit the following table

a) 1.5 ohms +/- 6 volt or 12 volt external resistor

b) 3.0 ohms +/- 12 volt internal resistor

c) 6.0 ohms +/- 24 volt

3) If the primary resistance checks NOT OK replace coil. If it checks OK continue to step 4

4) Check secondary resistance of the coil from the (-) to the high voltage connection. Resistance should fit the following table

a) 8,000 to 11,000 ohms +/- 6 volt or 12 volt external resistor

b) 8,000 to 11,000 ohms +/- 12 volt internal resistor

c) 8,000 to 11,000 ohms +/- 24 volt

5) If the secondary resistance checks NOT OK replace coil. If it checks OK continue to step 6

6) Connect a jumper form the (+) side of the coil to the (+) side of the battery.

7) Connect a jumper from the (-) side of the coil and leave it hang in air.

Disconnect the coil wire from the distributor

9) Holding the coil wire RUBBER INSULATION. Hold the metal end close to the engine (1/8” to 3/8”)

10) Ground the wire from the (-) side of the coil (step #7) and un-ground it.

a) If no spark occurred, recheck for proper application of #6 through #10

i) If still no spark replace the coil wire with a known good coil wire and continue with #10

ii) You MUST have spark in this step before continuing to next step.

If all else fails replace the coil with a known good coil. Coils have been known to pass the resistance check but break down under load

b) When spark occurs then proceed to next step.

11) Connect the normal wire from the vehicle to the (+) coil terminal and turn ignition ON.

12) Check voltage at coil (+) terminal.

a) No battery voltage. Repair vehicle wiring.

b) Normal battery voltage? Continue

13) Perform #7 through #10

a) If no spark occurred, recheck for proper application of #7 through #10

b) When spark occurs then proceed to next step.

14) Connect the (-) side of the coil.

15) Holding the coil wire RUBBER INSULATION. Hold the metal end close to the engine (1/8” to 3/8”)

16) Have assistant run starter motor (Turn key, press button, step on starter, etc)

a) When spark occurs then proceed with #17

b) If no spark occurs then proceed to POINTS NOT FIRING COIL

17) Plug coil wire back in distributor.

18) Remove a spark plug wire from a spark plug.

19) Connect the spark plug wire to a spare spark plug with the gap set to at least 0.035”. (1/8” to ¼” is better)

20) Position the spark plug so the threads are touching the cylinder head and the gap is visible.

21) Have assistant run starter motor (Turn key, press button, step on starter, etc)

a) When spark occurs then proceed with #22

b) If no spark occurs then proceed to NO SPARK TO SPARK PLUGS

22) Repeat #18 through #21 for each spark plug wire

a) When spark occurs at each spark plug then proceed

b) If no spark occurs then proceed to NO SPARK TO SPARK PLUGS

23) Remove spark plugs

24) Clean and gap them to 0.035”

25) You now should have spark at all plugs.




POINTS NOT FIRING COIL

1) Remove distributor cap

2) Insert a piece of paper between the contact points

3) Check voltage at the movable arm of the points

a) No battery voltage. Repair wiring from coil to points

b) Normal battery voltage? Continue

4) Turn ignition switch off

5) Rotate the engine such that the movable arm of the points rests on the top of the distributor lobe

6) Set the point gap to 0.020”

7) Holding the coil wire RUBBER INSULATION. Hold the metal end close to the engine (1/8” to 1/4”)

Have assistant run starter motor (Turn key, press button, step on starter, etc)

a) When spark occurs then proceed with #8

b) If no spark occurs

i) File points to remove pitting â€" repeat #4 - #7

ii) Replace condenser â€" repeat #4 - #7

9) Replace Rotor and cap continue with Step #17 above



NO SPARK TO SPARK PLUGS

If there is spark from the coil wire to the distributor and not to the spark plugs the problem is

Inside the distributor

Cap

Rotor

Spark plug wires



Inside the distributor

1) Check distributor cap for cracks and carbon tracks

a) If cracks or carbon tracks â€" Replace distributor cap

2) Check the rotor for carbon tracks

a) If carbon tracks â€" Replace rotor



Spark plug wires

Replace with known good spark plug wires

Return to Step #21 above



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Oddities - Weird thing I have found:

Wire terminal crimped to insulation - not the conductor.
Wire from distributor coil connection to points grounded / or broken.
Bolt where coil wire connects to the distributor grounded to coil.
Resistance from distributor body to block is not ZERO.
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Things to watch-out for:

Spark voltages are normally 5,000 volts to 15,000 volts and can be 40,000 volts.
Before beginning, make sure the coil wire and spark plug wires are dry and in good condition.
If the points are pitted in a short time, the coil may be the wrong voltage for the application and / or condenser may be defective.

[Jon S]

Jon,
Polarization is a procedure which matches the polarity for the generator and the voltage regulator by permitting a surge of current to flow through the generator, correctly polarizing it. Damage to electrical components can occur if polarities do not match.  The polarity of the generator must be set to match that of the voltage regulator.

Polarization of the generator should take place whenever the Battery, Generator, or Regulator are replaced or serviced.
                                      Bobby

The only reference to polarizing in my 1958 Shop Manual is under Section 12; p. 12-7 (7) in reference to "Installation of Generator."  The 1957 Shop Manual covers Battery Removal and Installation under Section 12 p. 12-6 (7).  It states a. Removal: "1. Disconnect battery cable and ground strap, 2. Remove two wing nuts and hold down clamp, 3. Remove battery, being careful not to damage the terminals.  b. Installation: 1. Install battery by reversing above procedure.  NOTE:  Care should be taken to tighten the wing nuts just enough to prevent vibration of the battery.  Avoid over-tightening of the nuts.

I have changed the battery in this car at least 9 times over the past 57 years and it has always been a simple remove and switch process as stated in the Shop Manual.  The 1958 has an additional bracket that extends from the wing nut to the radiator support that needs to be removed/re-installed.

I know many of my friends have battery disconnects on their batteries.  They simply turn the knob or flip the switch and start their cars.  They do not perform any polarizations.

[Matt Innocenzi]

Thank you all for the great ideas and suggestions.

Art - I checked the in line fuse and its good
Scot - I thought the same with the condenser and replaced it anyway with the new set of points.  No change.
Smedley - Yes, there is a very good chance it is flooded.  When I smelled the raw gas, I checked the floats in the carb and they were fine, but I bet there is a pool of it in the manfold/cylinders.  I will pull the plugs and blow out all of the gas. 
Dan - WOW, thank you!  I have a coil that I know is good, after I get rid of all the gas, I will try this other coil.  Again, I am getting spark, but come to think of it, the spark does look a little weak from previous times I have seen plugs fire. 
Jim - Look in the shop manual under charging system and in the introduction.  The Shop Manuals have it but if you are not aware of it or looking for it, it is very easy to miss.  There is only once sentence on it.  Very important to do to make sure your generator, battery, and VR are all in sync.

Will keep you posted with the flooding and coil...

Matt

[76eldo]

Have you tried a shot of starting fluid?

I had a 64 Coupe that would NOT start when it was cold and the choke was engaged unless I gave it a shot of starting fluid.

I sold it.

Brian

[savemy67]

In the engine - electrical section of my '67 Cadillac shop manual, page 6-31, it specifically states "do not attempt to polarize the generator" (alternator).  This strongly implies that polarization was used on earlier model cars with D.C. generators.

My 1958 Chevrolet shop manual, page 9-22, specifically mentions polarizing the generator whenever the bat/gen/reg are serviced.  I am fairly confident that the charging system for Chevrolets and Cadillacs were similar enough that the same service processes would apply.

For every GM make, my 1954 - 1963 Chilton manual states in each make's section (Chev, Pontiac, Buick, Olds, Cad) that polarization should be performed whenever the bat/gen/reg are serviced.

I do not want to polarize this discussion, but I do not think that the preponderance of documentation supporting the bat/gen/reg polarization service procedure constitutes mis-information.

Respectfully,

Christopher Winter

[Bob Hoffmann CLC#96]

Christopher,
THANK YOU FOR THE CORRECT INFORMATION.
Bob

[Jon S]

I will repeat there is NO NEED to polarize a generator when replacing a battery. If the generator/regulator is being replaced, that is a different story.

[joeceretti]

I've been watching and there has been no discussion at all about why a generator needs to be polarized and the causes of reverse polarization. The manual tells you to polarize your generator each time because they don't want to explain when and why it needs to be done and it is safer for the manufacturer to just tell you to do it every time. There is no significant danger in polarizing unless you hit the wrong terminal in error.

It does NOT need to be done as long as the polarity of the residual magnetism in the generator is still in the correct polarity for either a positive or negative ground system. Without getting into it 1) If you hook up your battery backwards in error  2) If you short things out, I will say, the wrong way or 3) If you have installed a new generator with an unknown polarity; these are the only times you need to be sure that the residual magnetism in the generator is polarized correctly.

It is interesting that nearly all voltage regulators also came with a little instruction sheet saying that when installing a new regulator you needed to "polarize the regulator."This also led, and still leads to a lot of "misinformation"on the subject. Their statements were warranted in so much as they were trying to protect themselves from the many many mechanics who had no clear understanding of the electrics in there car returning the "faulty"regulator due to burning the contacts.

So, after working on your electrical system, if you want to feel safe and good about it you can re-polarize, just to be sure. Do you NEED to? Not likely. Changing a battery? No need. Changing a regulator? Never, the mechanical regulators in the Cadillacs do not have any specific polarity HOWEVER most mechanical regulators, and these included, have contacts with a protective tungsten coating on ONE contact terminal and if electricity flows in the wrong direction the spark will also jump in the wrong direction resulting in your regulator needing a very quick replacement. So repolarizing after changing a regulator is not needed. However this statement in regard to changing a regulator needs to be qualified with the REQUIREMENT that you disconnect your battery before doing so but let's not get into an argument about which wire to pull off of the battery, just pull one off. Changing a generator? Every time.

I don't think it needs to be said, but I will say it, don't work on your electrical system with the battery connected.

As an addition, if you want to use a generator form a positive ground car in a negative ground car, and vice versa, you can. These generators work in both directions once polarized that way.

This thread should really get back to why Matt's car won't start.


 

[J. Gomez]

Matt,

Not sure if it was mention or not on the multiple threads above, too early in the morning and lack of coffee to get my brain cells going. 

Although you are getting spark at the plugs it may be a weak one if there is not a good +12V present at the + side of the coil while cranking.

If you have the conventional points and standard coil, the +12V will be supply from the starter solenoid on the yellow wire, ONLY while cranking.
Once the ignition switch is released the +12V is supply from the ignition switch via the resistance wire at the coil dropping the voltage to about +9V give or take.

Checked the “yellow” wire (disconnected it from the coil first) that is attached to the + side of the coil for a good +12V while cranking.

Good luck..!

[Matt Innocenzi]

Very interesting information on polarity, but to get back on track, is the polarity just a coincidence for the car not being able to start?  Any chance a polarity could fry a coil?  Seems unlikely, but I did find it strange that when I polarized the GEN light illuminated in the dash without the key in.

Brian - I tried the ether and no luck. 

J. Gomez - will give it a try with the 12V cranking.  If my memory serves me correctly, the standard voltage to the coil is 12V but the ballast resistor (incorporated within the wire on 1960 and newer) reduces it to about 7V in normal driving conditions.

It was 12 degrees this morning in DC, so I think I will wait until tomorrow's heat wave of 40 degrees to run these tests!

Matt

[Jon S]

Hello all,

I have a 1961 Cadillac Sedan DeVille I am trying to restore.  The generator light came on after I changed the battery so I wanted to polarize the system to make sure that was not the problem.  I connected a jumper wire between armature and battery terminals on the voltage regulator.  Unlike other times I had done this, I got a very tiny spark and heard a click in the voltage regulator.  Strangely, the GEN light illuminated in the dash without the keys even being installed.  Very strange.

Stranger still, I went to start it, and it just cranked over and over without starting.  I have fuel and I have spark.  Even with ether, it will just crank over and over.  Occasionally, it will spin faster as if it is going to catch, but nothing.

I checked the floats on the carb and they were within spec.  Changed the points for the heck of it, and still nothing.

Could the polarizing have done something weird or just coincidence?

Any thoughts or suggestions?

Thanks in advance,
Matt

Matt -

When was this car last running?  Did you charge the old battery prior to installing the new battery? 

[joeceretti]

I'm wondering, when you polarized the generator, how long did you connect the Gen/Armature to the battery terminal. It shouldn't/doesn't need to be connected for more than a very brief moment. You mean, after you touched it briefly the gen light illuminated and stayed that way? Or only while the jumper was installed to polarize?

You should get a tiny spark and the relay in the regulator should click over.

Have you opened your regulator to check if the points are stuck?

[Matt Innocenzi]

Jon, last time it was running was last week.
Joe, yes I touched the jumper wire for just a moment.  It gave a tiny spark, I heard the voltage regulator click and then the GEN light stayed illuminated until I tried to start the car.  I opened up the cover on the VR and all looks intact.

[Jon S]

Does the GEN light go out when cranking the car and come back on when you take the key out or was that a one time event?  If the GEN light is still on with key out, then points in the VR are closed and should be open.