Ignition problems

Anything Corvair related
Blair
Posts: 44
Joined: Sun Aug 06, 2017 9:03 pm

Ignition problems

Post by Blair »

I've been learning exactly how the ignition system works, and I've narrowed it down to a few things I think is why my 64 monza won't start. It's either the coil or the condenser on the coil that goes to the distributer. Are all condensers the same or will I have to order one specifically? Would the car start even if the condenser was bad, and if I've been trying to start it with a bad condenser would it damage the distributer? If anyone has diagrams of all the parts and wiring for a 64 monza ignition system, it would be a lot of help. And any input about similar situations or advice will be appreciated.
Jerry Whitt
Posts: 887
Joined: Thu Sep 26, 2013 2:42 pm

Re: Ignition problems

Post by Jerry Whitt »

The condenser in the distributor absorbs electrons as the points are starting to open. As the cam opens the points, electricity is in motion and tries to jump the gap as the points move to full open. The speed at which the points open is relatively slow compared to the speed of electricity. The process keeps the points from arcing. The electrical system also has a resistor in the primary wiring system to help cut down the voltage, to also help prevent arcing and in turn damaging new points.

There is also another condenser attached the coil. This is designed to cut down on radio interference. The condensers are made from long strips of foil, looking like aluminum foil used for cooking. The strips are about 8 feet long, and are coated on one side so that as the metal is rolled into
a small package, the electrons do not pass to the piece touching it.

The condensers have a capacity know as "micro farads." The capacity will very with the physical size of the condenser. Check your specifications for the capacity your system should use. If the wrong capacity is used, the points can be damaged.

Noted a phrase you used, "won't start". When working with technical issues, the words "won't" and "can't" should not be used.

The MACHINE does not have an attitude. The person trying to solve the problem might have an attitude. A better thought process is " I have not solved this problem yet!"

Good luck, hope this will help.
Jerry Whitt
ASE CERTIFIED MASTER TECHNICIAN
Retired
Hemet, Callifornia
65 Monza, purchased new
65 Corsa convertible
User avatar
terribleted
Posts: 4588
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Ignition problems

Post by terribleted »

Condenser on the coil does not effect the ignition or starting, it is strictly for radio interference. Perhaps if shorted or connected incorrectly it could make some issue? Disconnect the coil condenser to make sure it still doesn't start, then forget about it as your issue.

Blair I have not seen yet where you have specified what you mean by will not start. Does the engine turn over (crank) with the starter when you tune the key or is the issue that it will not fire when cranking? I will assume that it cranks. Is there spark at the plugs when cranking? Is there fuel in the carbs? Does it spit and pop at all (try to start)? Have you done a compression test and if so what are the results? Did you ever verify the distributor installation...is it clocked correctly? Why do you think it is a bad coil?

Look at the manuals online that were previously posted to you or get in the paper copies I suggested you buy weeks ago to get the data you are looking for.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 11872
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: Ignition problems

Post by bbodie52 »

Blair wrote:Tue Dec 05, 2017 11:54 pm

I've been learning exactly how the ignition system works, and I've narrowed it down to a few things I think is why my 64 Monza won't start. It's either the coil or the condenser on the coil that goes to the distributor.
For effective troubleshooting, it is important to understand what "normal" looks like when the car is functioning properly. If the car will not start, you need to logically work your way through the fuel system, ignition system, etc. to determine which part is not functioning normally. If the engine is cranking when you attempt to start the car, the presence of a fuel/air mixture from the carburetors and a properly timed the ignition spark at each spark plug will normally allow the engine to start. So on your Corvair, what is missing?

In your opening trouble description, you provide very little information on your car's history or the troubleshooting techniques you used that lead you to the conclusion that it is "either the coil or the condenser on the coil".

Have you confirmed that your distributor is still fitted with ignition points and condenser? Corvairs have sometimes been upgraded by an owner to make use of an electronic breakerless ignition system that eliminates the original points and condenser. Before we go too far with trying to help you to troubleshoot your Corvair, I wanted to confirm that your ignition system is a stock original configuration and has not been modified in some manner.

When you say that your Corvair will not start, what exactly will it do? Will the engine starter crank the engine at a normal startup speed? If yes, have you confirmed that the carburetors have fuel in them? (An easy way to check is to look down the throat of each carburetor after removing the air cleaner. Hold the choke open and open the throttle manually while looking down the carburetor throat. You should see a jet of gasoline squirt into the throat as you open the throttle. This is a simple way of utilizing the accelerator pump inside the carburetor to squirt fuel into the carburetor throat, which occurs each time the throttle is opened. If fuel is present in the float bowl the accelerator pump will force a small amount of gasoline through an internal passage to spray the fuel into the carburetor throat as the throttle is opened.
Carburetor Accelerator Pump Action
Carburetor Accelerator Pump Action
If you have confirmed the availability of fuel in the carburetors, have you checked for the presence of an ignition spark as you crank the engine? A simple way to test this is to unplug the coil wire from the center of the distributor cap. Hold the wire metal contact close to a metal object that will provide chassis ground. While having an assistant crank the engine check to see if a spark is produced that will jump a small gap between the wire and chassis ground.

If no spark is produced, you will have to do some troubleshooting to determine the cause. The condition of the ignition points would be one area to check. As shown in the illustration below, you should be able to observe the ignition points opening and closing as you crank the engine with the distributor cap removed. (The points are nothing more than an on/off switch. When closed, they provide a ground connection to the ignition coil negative terminal. This allows current to flow through the coil to energize the internal coil windings. When the points open, the magnetic field that has been created inside the coil will collapse, which causes a high-voltage discharge from the coil center terminal. This high-voltage output is conducted from the coil to the center terminal in the distributor cap. The rotor inside the distributor then conducts the high-voltage from the center terminal to one of the six terminals around the perimeter of the distributor cap, so that the voltage can then be conducted by a spark plug wire to the spark plug. Finally, the high-voltage passes through the spark plug and jumps the gap at the end of the spark plug to ignite the fuel/air mixture inside the combustion chamber.

If you have no spark produced as you crank the engine, and you determine that the ignition points are opening and closing, you should check (using a multimeter) for the presence of voltage at the coil positive terminal with the ignition key is in the ON position. You should be able to measure approximately 12 V DC between the coil positive terminal and chassis ground.

The video below does a good job of illustrating the basic function of an automobile ignition system that utilizes ignition points and condenser…

Assuming your Corvair is still fitted with a stock ignition system with coil, points, condenser, etc...

DC power is provided to the coil positive terminal from two sources. On most Corvair model years a single wire is routed between the coil positive terminal and the two-circuit plastic connector near the starter. This wire is spliced to two wires at that point. One wire is connected to the starter solenoid, while the other wire is routed to the multi-connector near the charging system voltage regulator. The wire coming from the starter solenoid provides a full 12 VDC to power the coil, but only when the ignition key is turned to START to energize the starter and crank the engine. The coil receives a full 12 VDC power source as long as the engine is being cranked by the starter. The higher voltage fed to the coil increases the spark plug voltage to help the cold engine to start at cranking speeds. This voltage is shut off when the key is released and the starter disengages. The other wire that leads to the multi-connector is a special resistor wire. It provides the coil with a continuous nominal 7 VDC to keep the engine running when it is no longer being cranked by the starter. This reduced voltage comes from the ignition switch in the ON position. It is a full 12 VDC (battery voltage) from the ignition switch to the multi-connector, and is then reduced by the special resistor wire to a nominal 7 VDC for normal continuous engine operation. The reduced voltage is adequate to keep the engine running, but the lower voltage helps the coil to run cooler and also prolongs the life of the ignition points by reducing arcing and burning as the points open and close.

The black wire on the coil negative terminal connects to the distributor ignition points, which serve as an on/off switch. When closed they ground the coil primary winding to energize the coil and build an electro-magnetic field. When the points open the electro-magnetic field collapses, causing a high voltage discharge from the coil secondary winding to the distributor cap center terminal. The rotor then routes this high voltage to one of the six spark plugs to cause a spark to jump the gap on the plug to ignite the fuel-air mixture in the combustion chamber. (This is all synchronized with the engine so that each spark plug fires at the correct moment when the piston is at the top of the compression stroke and ready for the power stroke).

If there is a second wire on the coil negative terminal (-), routed to the wiring harness, it is a sensor wire for a tachometer. This wire allows a tachometer to count the voltage pulses that occur as the points open and close, which are displayed as an RPM reading on the tachometer.

If a condenser (capacitor) is mounted on the side of the coil, it serves as a radio interference noise suppression device. It mounts to the coil bracket, and its lead goes to the positive (+) terminal on the coil

Refer to the engine wiring schematic in the shop manual for your model year to see the details of this wiring illustrated, and to see the wire color codes. On some early models, a separate wire is routed from the starter solenoid, all the way to the coil positive terminal, and the other resistor wire is also routed all the way to the coil, with both wires joining at the coil positive terminal. But on most model years the two wires join at the plastic connector near the starter, leaving a single wire to be connected to the coil positive terminal. Wire color codes vary with different model years.
Image

Left-click the image to enlarge for better viewing…
1964 Combined Passenger Compartment & Engine Compartment Wiring Diagram
1964 Combined Passenger Compartment & Engine Compartment Wiring Diagram

If you can perform some of the tests described above, please provide a detailed description of the results of each of your tests. Let us know what you tested for, how you tested, and the results. If the fuel system appears to be normal but the ignition system is not producing a spark, you can begin to focus on the ignition system to determine why no spark is produced. There could be a lack of voltage being fed to the ignition coil, a bad electrical connection between the coil and the ignition points, or pitted/burned/damaged the ignition points, or possibly a shorted condenser. This portion of the ignition system is known as the PRIMARY ignition system. The other part is known as the SECONDARY ignition system. It is the high-voltage part of the ignition system made up of the thick spark plug wires that route from the center of the coil to the distributor cap and from the distributor cap to each of the six spark plugs.

When I started working on cars back in the 1960s, I discovered a series of books that were part of a series published by Petersen's Publications that constituted the Hot Rod Magazine technical library. Each book focused on a different aspect of automotive technology, including cams, valves, and exhaust systems, clutches and transmissions, brakes and suspension systems, and ignition and electrical systems.

These books are inexpensive and can be found from sources like Amazon.com and on eBay in good used condition for only a few dollars each. As a teenager in the 1960s I found that they did an excellent job of teaching me the fundamentals so that I began to understand how cars actually worked. Reading these books give me a much better understanding of the material that I was reading in the Corvair Shop Manual. Understanding how things in the car were supposed to work help me to do a much more effective job at troubleshooting and fault isolation so that I can figure out what was wrong or why something wasn't working!

If you are willing to invest some of your spare time, I would strongly recommend the book below to help you learn the principles of the electrical systems in your Corvair. The books were written during the time period that the Corvair and other classic cars were manufactured, so they cover the technology that was in use in the 1960s and 1970s. I believe you will find that this book will fill in the knowledge gaps and will help you to be a more effective mechanic as you learn to maintain your classic Corvair.

:link: https://www.amazon.com/ignition-electri ... on+systems
Image

I have attached sections of the 1961 Corvair Shop Manual and the associated 1964 supplements to refer to if you don't have a copy.

:chevy:
Attachments
1961 Chevrolet Corvair Shop Manual - Section 7 - Engine Tune-Up.pdf
1961 Chevrolet Corvair Shop Manual - Section 7 - Engine Tune-Up
(644.51 KiB) Downloaded 32 times
1964 Supplement - Chevrolet Corvair Shop Manual - Section 7 - Engine Tune-Up.pdf
1964 Supplement - Chevrolet Corvair Shop Manual - Section 7 - Engine Tune-Up
(931.65 KiB) Downloaded 30 times
1961 Chevrolet Corvair Shop Manual - Section 8 - Electrical Systems.pdf
1961 Chevrolet Corvair Shop Manual - Section 8 - Electrical Systems
(3.28 MiB) Downloaded 30 times
1964 Supplement - Chevrolet Corvair Shop Manual - Section 8 - Electrical Systems.pdf
1964 Supplement - Chevrolet Corvair Shop Manual - Section 8 - Electrical Systems
(1.95 MiB) Downloaded 42 times
1961 Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems.pdf
1961 Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems
(1.31 MiB) Downloaded 29 times
1964 Supplement - Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems.pdf
1964 Supplement - Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems
(3.99 MiB) Downloaded 28 times
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible
Blair
Posts: 44
Joined: Sun Aug 06, 2017 9:03 pm

Re: Ignition problems

Post by Blair »

Sorry everyone I'm usually half asleep when I post on here so I don't give in depth details of my car. I apologize as it is probably frustrating but everything that is posted is helpful to me. I just ordered the last copy on Amazon of the basic ignition and electrical systems book/magazine. I've always had an interest in old cars and mechanical things but I never had a chance to tinker with anything until recently. I'm young, broke, pretty clueless compared to most of you, but passionate about this and I've learned a lot so far. Everyone says I have a cool car and asks why I bought a piece of crap and it just makes me smile because I love it. But anyway, yes it turns over but will not start. It doesn't sputter so I'm guessing it's not getting any ignition sparks. I will check for the ignition sparks in the center wire on the distributer cap by holding it close to the chassis and cranking it as you said, and will refer to your posts on Friday when I go to the garage. I had the distributer taken out and I attempted to re-seat it properly, but will double check and try again. I replaced about 90% of the connectors in the engine compartment so I don't think connection is the problem. The ignition video provided will be very helpful. Thank you everyone
Blair
Posts: 44
Joined: Sun Aug 06, 2017 9:03 pm

Re: Ignition problems

Post by Blair »

It also does have an electrical ignition system.
User avatar
terribleted
Posts: 4588
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Ignition problems

Post by terribleted »

If you see no spark, replace the electronic ignition unit with standard points and condenser (the one inside the distributor) and see if it fixes it. Could just be a failed electronic ignition module.

It is a good idea when running an electronic ignition to carry an extra point plate with points and condenser installed and gapped ready to go in the glovebox. If you have an electronic ignition failure you can be back on the road in like 5 mins by swapping the stock plate in...take only a screwdriver:)
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
64powerglide
Posts: 1604
Joined: Tue Mar 25, 2014 9:18 pm
Location: Kalamazoo Mi..

Re: Ignition problems

Post by 64powerglide »

Just pull one of the spark plug wires & stick your finger on the metal part of the wire & have someone crank it over, if your not getting any spark you won't feel a thing. ::-):
64Powerglide, Jeff Phillips

Kalamazoo, Mi..
Post Reply

Return to “Corvair Talk”