Electronic Ignition Problem
#1
Electronic Ignition Problem
Last edited by LinWest; 04-20-2013 at 10:55 AM. Reason: Answered my own question
#2
#3
#5
If you are considering upgrading to 'electronic ignition' there are several options. I swapped the points for Fords DuraSpark ll electronic ignition, but there are a number of options. If you are having problems with your current ignition system describe the problem perhaps a member can help??
#6
ABC's of standard mechanical points and condenser
Nice picture of a standard set of ignition points and condenser. This is not considered "electronic".
Assuming you want to know how these works or perhaps someone else wants to know....
The ignition switch routes power to the pos. side of the coil then through the primary wires of the coil to the mechanical points where there is a capacitor (condenser) connected.
When the points open, the capacitor/condenser charges up like a tiny battery. When the points close the primary system is taken to ground and the capacitor discharges.
When this happens, there is a surge of electron flow (current) through the primary system causing the secondary windings in the coil to multiply the voltage in the secondary winding to above 50,000 volts. In fact, the coil is a step up voltage transformer in this application.
The High voltage from the coil wants to go to ground and it does so by leaving the top of the coil, goes to the distributor cap where it is routed by the rotor or bug to the spark plug wire then to the spark plug where it jumps the gap on the spark plug to ground. Jumping the gap creates a spark and there is an explosion in the cylinder if the gas to air ratio is proper.
The plug receiving the voltage is determined by the position of the rotor (bug) on the top of the distributor shaft.
The other end of the distributer is connected to the oil pump and it turns as the engine turns over.
There are cams on the distributer shaft which will press against the points to open and close the points at the proper time as the pistons reach or descend from top dead center on the compression stroke.
The setting of the distributor rotor in relation to the proper piston being at the proper point before or after TDC is called timing. You can move the distributor to make it line up to the proper plug wire at the proper time and that movement also effects the opening of the points which must open and close at the proper times.
To move the distributor to set timing, loosen the bolt holding a clamp on the base of the distributor.
To work properly, the mechanical points have to be set with the proper gap which determines how long the condenser/capacitor will be charging and discharging. It is called point gap or "dwell" if being measured by a meter.
To set the point gap, remove the bug (rotor) so you can see the points open and shut. Rotate the engine by hand or with the starter until the points are riding on the highest point of the cam on the shaft. This will have the points open to the proper gap.
Measure the gap with a feeler gage. If it needs to be adjusted, lightly loosen both screws on the point's base and use a flat screw driver to open or close the point gap by moving the base slightly in the proper direction. There is a slot in the base for the screwdriver blade.
When the gap is set, retighten the screws, recheck the gap, replace the rotor (bug) and replace the cap.
Start the engine and check your timing and dwell (point gap) using a meter if you have them. Disconnect the vacume line at the distributor when checking and setting timing.
A vacume gage is a great investment on these old trucks. Disconnect the vacume line at the distributor and hook the vaccume guage to the vacume line going up to the carb. Set your timing for maximum vacume.
Assuming you want to know how these works or perhaps someone else wants to know....
The ignition switch routes power to the pos. side of the coil then through the primary wires of the coil to the mechanical points where there is a capacitor (condenser) connected.
When the points open, the capacitor/condenser charges up like a tiny battery. When the points close the primary system is taken to ground and the capacitor discharges.
When this happens, there is a surge of electron flow (current) through the primary system causing the secondary windings in the coil to multiply the voltage in the secondary winding to above 50,000 volts. In fact, the coil is a step up voltage transformer in this application.
The High voltage from the coil wants to go to ground and it does so by leaving the top of the coil, goes to the distributor cap where it is routed by the rotor or bug to the spark plug wire then to the spark plug where it jumps the gap on the spark plug to ground. Jumping the gap creates a spark and there is an explosion in the cylinder if the gas to air ratio is proper.
The plug receiving the voltage is determined by the position of the rotor (bug) on the top of the distributor shaft.
The other end of the distributer is connected to the oil pump and it turns as the engine turns over.
There are cams on the distributer shaft which will press against the points to open and close the points at the proper time as the pistons reach or descend from top dead center on the compression stroke.
The setting of the distributor rotor in relation to the proper piston being at the proper point before or after TDC is called timing. You can move the distributor to make it line up to the proper plug wire at the proper time and that movement also effects the opening of the points which must open and close at the proper times.
To move the distributor to set timing, loosen the bolt holding a clamp on the base of the distributor.
To work properly, the mechanical points have to be set with the proper gap which determines how long the condenser/capacitor will be charging and discharging. It is called point gap or "dwell" if being measured by a meter.
To set the point gap, remove the bug (rotor) so you can see the points open and shut. Rotate the engine by hand or with the starter until the points are riding on the highest point of the cam on the shaft. This will have the points open to the proper gap.
Measure the gap with a feeler gage. If it needs to be adjusted, lightly loosen both screws on the point's base and use a flat screw driver to open or close the point gap by moving the base slightly in the proper direction. There is a slot in the base for the screwdriver blade.
When the gap is set, retighten the screws, recheck the gap, replace the rotor (bug) and replace the cap.
Start the engine and check your timing and dwell (point gap) using a meter if you have them. Disconnect the vacume line at the distributor when checking and setting timing.
A vacume gage is a great investment on these old trucks. Disconnect the vacume line at the distributor and hook the vaccume guage to the vacume line going up to the carb. Set your timing for maximum vacume.
#7
I edited my post because I answered my own question.
I will be installing an electronic ignition, thanks to the information available in this forum. Thank you for sharing your knowledge.
I plan on purchasing a petronix kit from o Reilly auto, as I am nearing completion of my 1965 F250 CS rebuild. Nothing special, just looking for a dependable truck with mostly stock parts.
Thank you all again.
I will be installing an electronic ignition, thanks to the information available in this forum. Thank you for sharing your knowledge.
I plan on purchasing a petronix kit from o Reilly auto, as I am nearing completion of my 1965 F250 CS rebuild. Nothing special, just looking for a dependable truck with mostly stock parts.
Thank you all again.
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#8
Linwest,
Nice clean engine.
I am of the old old school, trying to keep my 1962 4x4 half ton truck as original as I can including the old style ignition, old type single master cyclinder, etc. That being said, I had to add a/c, redo the interior and paint it blue vice green and red/white or I would not drive it as a daily driver.
I suggest you shop around on the electronic ignition, prices vary wildly between parts stores on the same parts made by the same mgf. I am sure you know this if you have rebuilt the truck. I am a fan of the list on the top of the forum if they are not in a state I am currently boycotting for political reasons.
Please post sme pics of your project.
Nice clean engine.
I am of the old old school, trying to keep my 1962 4x4 half ton truck as original as I can including the old style ignition, old type single master cyclinder, etc. That being said, I had to add a/c, redo the interior and paint it blue vice green and red/white or I would not drive it as a daily driver.
I suggest you shop around on the electronic ignition, prices vary wildly between parts stores on the same parts made by the same mgf. I am sure you know this if you have rebuilt the truck. I am a fan of the list on the top of the forum if they are not in a state I am currently boycotting for political reasons.
Please post sme pics of your project.
#10
When you see an old guy touch and test his brakes far before he gets to the stop sign or light you can bet he has had the old single master cyclinder fail on him. I learned my lesson driving a 38 fully loaded hay truck at age age 16 when I sailed right through the only red light in downtown Newkirk, OK. at just after noon. Of course, there were no one else in town so it was no big deal.
#11
#12
To update those interested, I installed the pertronix kit. Because this forum is awesome, I knew to install an o-ring on the distributor shaft under the magnet, to lift the magnet 1/8". It didn't work without the o-ring, so that knowledge saved me considerable time, effort, and money.
It ran great at first.
The longer the engine ran, the less it wanted to idle, and the rougher it ran. I wasn't able to diagnose it because the wife needed me to replace a light fixture.
I am thinking the miss fire/no idle is due to a faulty alternator, and as the battery ran low, the ignition system suffered. Another option is I might not have the carburetor adjusted correctly. The two barrel carb sits atop a bored 390, so I might have to adjust the jets/needles to compensate for the extra cubic inches. All components, besides the alternator, are new, so I am not sure what it could be.
Other than engine performance I will be rebuilding the brake system, installing new exhaust pipes, new tires, and a few other smaller items. Hopefully I will have a dependable light duty work truck.
Also, the wires look like hell draped across the front of the engine. Any products or ideas on how to secure the distributor wires, oil sending wires, etc.?
And...where can I find a new oil sending unit? They are not easily found at retail auto supply.
(Ignore the pinched radiator hose. The engine has not been hot enough to need it yet.)
It ran great at first.
The longer the engine ran, the less it wanted to idle, and the rougher it ran. I wasn't able to diagnose it because the wife needed me to replace a light fixture.
I am thinking the miss fire/no idle is due to a faulty alternator, and as the battery ran low, the ignition system suffered. Another option is I might not have the carburetor adjusted correctly. The two barrel carb sits atop a bored 390, so I might have to adjust the jets/needles to compensate for the extra cubic inches. All components, besides the alternator, are new, so I am not sure what it could be.
Other than engine performance I will be rebuilding the brake system, installing new exhaust pipes, new tires, and a few other smaller items. Hopefully I will have a dependable light duty work truck.
Also, the wires look like hell draped across the front of the engine. Any products or ideas on how to secure the distributor wires, oil sending wires, etc.?
And...where can I find a new oil sending unit? They are not easily found at retail auto supply.
(Ignore the pinched radiator hose. The engine has not been hot enough to need it yet.)
#13
#14
Did she run fine without the idle problem before you converted to electronic ignition? If so, heat expansion may be your problem.
You may have a failing electronic module, it is an engineering fact that out of several million manufactured items, there will be a certain number of failures. Electronics tend to fail as they heat up and expand, especially where the wires attach to the internals.
Same with a tiny crack in the distributor cap or a flaw in a coil.
You can dress up wiring using wiring looms or if you want to take the time, use stainless steel tubing or even black plastic tubing like what is used on evap air units, or aquariums, or drip irrigation or sprayers, etc.
You may have a failing electronic module, it is an engineering fact that out of several million manufactured items, there will be a certain number of failures. Electronics tend to fail as they heat up and expand, especially where the wires attach to the internals.
Same with a tiny crack in the distributor cap or a flaw in a coil.
You can dress up wiring using wiring looms or if you want to take the time, use stainless steel tubing or even black plastic tubing like what is used on evap air units, or aquariums, or drip irrigation or sprayers, etc.
#15
I had a problem where it ran fine until it got warm, then started running bad. Problem was the gasket under the carb. When things got hot, it allowed a vacuum leak. One way to check this is to spray carb cleaner around the base of the carb while it's running. The carb cleaner will create a temporary airtight seal of the leak and you will notice a difference in idle. If you do, replace that gasket. Also check for other vacuum leaks.