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Discussion Starter #1
First post so please do easy on me :)
Helping my nephew get a original 66 289 auto trans, fastback running. Car ran a few year ago and they let her sit as a garage queen.

She cranks but just won’t start. Spark is strong at the coil wire but weaker at the plug ( normal or not?)

Car belonged to his granddad. He would like to get her running and drive her around. Timing seems okay. Rotor points to driver seat at TDC. Distributer has the pointless Igniter by Pertronix (will check the gap again but we can’t find the glass gap gauge and don’t know the proper gap. Current gap does not seem bad.
Holly 2bbl carb. Get fuel and also tried a shot of starter fluid. No luck.

Wants to start when we crank the engine. we just can’t seem to get the engine to fire up and run. You can hear the engine want start when we crank the engine but she just start. At our first attempt before changing the items below, she almost started and backfired once and now she just cranks fine but won’t run.

So far we have done the following:
New battery
New ignition wires (6k ohms now, was 15k ohm on the old wires)
New coil ( now 1.4 ohm +-, and 14 ohm high side)
New plugs ( .34 gap)
New cap and rotor

Attached pic of the distributer for some reference.


3E61FB91-E45D-4FE0-8010-9B88F2A7B170.jpeg
3133357F-00BF-4157-8E88-194E6A315CC9.jpeg
 

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OK, stop buying stuff. Random parts replacement is not going to do it.

It certainly acts like a weak spark, so the #1 suspect is what creates that spark, the module in the distributor. These have certainly been known to fail. Simple cheap test- Put points and condenser in and it should run. An easier suggestion than you might think, you've replaced everything else.

I can't help wondering why it has a GM ignition resistor bolted to the top of the engine. Has the resistance wire in the under-dash harness been cut/bypassed/removed?
 

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If the car sat for a few years I would suspect a fuel problem such as a gummed up carb. You said you tried starting fluid with no effect but I'm still suspecting a fuel problem.
 

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Tend to agree with awhtx on a fuel problem. might be time to take the carb apart and give it a good cleaning and install new needle and seat as well as the gaskets. Contemporary fuels wreak havoc on carbs when they sit without running for a long time. Good time to check the fuel pump and change out fuel filter as well.
 

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Discussion Starter #5
OK, stop buying stuff. Random parts replacement is not going to do it.

It certainly acts like a weak spark, so the #1 suspect is what creates that spark, the module in the distributor. These have certainly been known to fail. Simple cheap test- Put points and condenser in and it should run. An easier suggestion than you might think, you've replaced everything else.

I can't help wondering why it has a GM ignition resistor bolted to the top of the engine. Has the resistance wire in the under-dash harness been cut/bypassed/removed?
Hello GT,
Is there a way to test the existing module?

I’ll get some points and condenser and we are not sure about the wiring but will look on YouTube. we have no old parts and his grand pappy passed away a while ago.

I know the car had some key ignition issue before (years ago) but now sure if when or how that was repaired. I’ll ask but his dad is not mechanically inclined (me to buy better than his dad).

I did see the resister but not sure what that was about.

Since we don’t have any of the old ignition parts I wonder if it’s easier to train test the current module?

thank you and be safe.

fish
 

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Discussion Starter #6
Tend to agree with awhtx on a fuel problem. might be time to take the carb apart and give it a good cleaning and install new needle and seat as well as the gaskets. Contemporary fuels wreak havoc on carbs when they sit without running for a long time. Good time to check the fuel pump and change out fuel filter as well.
Even when we didn’t put any fuel from the car down the barrels and just use the starter spray fuel, it wouldn’t start.
Do you still suspect the carb needs a good cleaning?
 

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Um, if the problem is the carb, spraying starting fluid would allow it to start for 2-3 seconds. Since it's not doing that, while the carb may be junk, it's an ignition problem.

Check the voltage from the firewall to the coil. It should be something like 7V. If it's 12V, then someone has been busy under the dash, which would explain the GM resistor. The small post marked "IGN" on the solenoid is supposed to supply a full 12V to the coil when the starter is engaged. Check to see if that circuit is compromised.

It might cost you $10 to switch over to stock point ignition. But the wiring needs to be checked, especially since it seems to have been modified.

If the under-dash resistance wire is missing, Rock Auto has it for $20. That would be my preference, rather than use that GM resistor. I suspect, from the photo, that the 12V start connection is no longer capable of reaching the coil because of it.

I have installed many electronic modules in various cars. My own? No. Why? Because they are occasional use fun cars. My '55, for example. I have driven to many events, gone for fun drives, etcetera, but since the system was designed for daily use, I have not needed to adjust the points in maybe 20 years.
 

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Keep in mind that if you go back to points and condenser and you have (what looks to me like) Pertronix electronic ignition, an electronic ignition coil might roast those points. It did for mine though it took a week or two. I'd get another Pertronix personally. They are so much easier to set up, gap and go than points. Also, if someone cut out the resistor wire they'd probably toast very quickly. Pertronix I units are quite reliable. Pertronix II and III I have heard tend to blow much more. Hopefully it says what you have. Usually II and III are performance upgrades and that's where people start messing with stuff and ripping out restance wires and so forth. I run my Pertronix I with stock wiring and she runs great. Yours looks like a Pertronix I for single advance distributor.

What about you choke? Especially if it is cold out you may need to adjust the choke. Or just hold the choke open by hand. Wear thick gloves incase of a backfire. Also helps to know if you have an electric choke or manual. If it's the latter you need to set that with a manual control. If not, then it needs current to warm up and open.

Also what about your ignition coil? Are the terminals tight, clean and correct? Does it match your pertronix setup? And battery charge. Make sure the battery is good and charged up. Looking at spark and determining if it's weak or strong by eyeballing it isn't always a good way to tell.

You might also do well to check base timing. Bring the #1 to TDC and your rotor button on distributor should be near 3 o'clock which should be the #1 cyl distributor button Also, timing marks on the balancer should be around 0. If you are on the intake stroke. If you are on exhaust it will off 180. You can take the valve cover off to see when the intake valve is opening. Some prefer to just feel for the pressure. I've done it by watching the gauge on a compression tester building up and then feeling the cylinder with a screwdriver down the hole as I turned motor slowly by hand. Turning a dead engine with all the other plugs in by hand can be daunting so prepare to crank it with socket on the crank pulley center bolt. I worked with a guy who was crazy strong and would just rotate my engine for me by hand grabbing the pulley :p Million was to check timing stilled. Much easier with a light and running engine.
 

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Discussion Starter #10
Thanks...does anyone now how to test the Ignitor module?

The spark from the coil wire is 3-4x hotter than the spark at the plug. We live in Cali (please don't kill me....I know) and my nephew lives close to San Dimas. Maybe they can test the unit for him.

I still have my Sun T-light but I can't find my old Sears dwell/tach meter. Have not used it since I sold my 70 Monte Carlo (with a 4 speed muncie). Tried to copy a Hot Rod project car. So would prefer to try and see if this is my issue.

Thank you for the info. Will focus on the dist module and try to test it. If not, will call them and see if they can test it.

Thank you and be safe.
 

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Might be a timing issue in addition. The position of the vacuum advance canister looks odd to me. Looks like it is point to 5 o'clock ish, should be more 7ish. Or the distributor is off by one tooth. Mark the Cylinder #1 pick-up point on the metal part of the distributor using a Sharpie so you can see there it is. Bring #1 to TDC (compression stroke) and check the harmonic balancer. The easist way is to use a piston stop. If you don't have one use a straw and find two equal points before and after TDC. TDC is exactly in the middle. With #1 at TDC the rotor at the distributor should point to the mark of the pick-up. Timing would not be great, but the engine should fire up.

Usually if the timing is off you get some misfire from time to time while cranking. So maybe you don't have a spark or fuel in addition.
 

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Here is a picture of the rotor at the #1 pick up mark.


Sent from my iPhone using Tapatalk
 

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Discussion Starter #13
Might be a timing issue in addition. The position of the vacuum advance canister looks odd to me. Looks like it is point to 5 o'clock ish, should be more 7ish. Or the distributor is off by one tooth. Mark the Cylinder #1 pick-up point on the metal part of the distributor using a Sharpie so you can see there it is. Bring #1 to TDC (compression stroke) and check the harmonic balancer. The easist way is to use a piston stop. If you don't have one use a straw and find two equal points before and after TDC. TDC is exactly in the middle. With #1 at TDC the rotor at the distributor should point to the mark of the pick-up. Timing would not be great, but the engine should fire up. Honestly it was so hard to stop at the TDC when we cranked the engine. Might need to remove the plugs and then see what we can do to ensure we are at TDC. But I think we are pretty close.

Usually if the timing is off you get some misfire from time to time while cranking. So maybe you don't have a spark or fuel in addition.
Hello 4SF. Thank you. We tried to adjust the dist timing at TDC (facing the driver or the 1pm position) and just left it at a adjustable and snug but what you see is not were we had it when we tried to start it. What you see in the picture is the dist loosened a bit as we tried to start the engine and see what dist position worked the best, the 1PM/driver position seemed to allow the engine want to start but won't (almost want to start).

I text my nephew to check the ohm wires on the dist module and also to test the output into the coil as Mr GT suggested earlier.

Thank you and be safe.

Thank you and be safe.
 

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Fact: the car has been sitting for years. Does it have compression? Dry cylinders (from sitting) won't have enough compression to suck in air and fuel. Also, note to Fishy, saying you have an "original 66 with 289" leads the members here to look at different problem areas. 1966 Mustangs didn't come with electronic ignition. A car parked in a garage for years won't lose it's ignition/spark timing. Since you replaced the cap & wires, did you make certain that you got the firing order correct on the cap? I'd pull the spark plugs again and do a dry & wet compression test (or have a friend help if you don't have a tester). A quick "cheat", as it were, would be to pull the plugs, squirt a little oil or trans fluid in each cylinder, disconnect the coil wire, crank the engine over. Then install the plugs and try to get it to fire with starting fluid (or a dribble of gas into the carb).
 

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Discussion Starter #15
Fact: the car has been sitting for years. Does it have compression? Dry cylinders (from sitting) won't have enough compression to suck in air and fuel. Also, note to Fishy, saying you have an "original 66 with 289" leads the members here to look at different problem areas. 1966 Mustangs didn't come with electronic ignition. A car parked in a garage for years won't lose it's ignition/spark timing. Since you replaced the cap & wires, did you make certain that you got the firing order correct on the cap? I'd pull the spark plugs again and do a dry & wet compression test (or have a friend help if you don't have a tester). A quick "cheat", as it were, would be to pull the plugs, squirt a little oil or trans fluid in each cylinder, disconnect the coil wire, crank the engine over. Then install the plugs and try to get it to fire with starting fluid (or a dribble of gas into the carb).
OK, will remove the plugs, make sure it’s on top dead center and then take a compression check also why the plugs are out I believe a ****ty be about 140?

Will also do some other checks while we are under the hood today.

Thanks and be safe all
 

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Discussion Starter #16
Um, if the problem is the carb, spraying starting fluid would allow it to start for 2-3 seconds. Since it's not doing that, while the carb may be junk, it's an ignition problem.

Check the voltage from the firewall to the coil. It should be something like 7V. If it's 12V, then someone has been busy under the dash, which would explain the GM resistor. The small post marked "IGN" on the solenoid is supposed to supply a full 12V to the coil when the starter is engaged. Check to see if that circuit is compromised.

It might cost you $10 to switch over to stock point ignition. But the wiring needs to be checked, especially since it seems to have been modified.

If the under-dash resistance wire is missing, Rock Auto has it for $20. That would be my preference, rather than use that GM resistor. I suspect, from the photo, that the 12V start connection is no longer capable of reaching the coil because of it.

I have installed many electronic modules in various cars. My own? No. Why? Because they are occasional use fun cars. My '55, for example. I have driven to many events, gone for fun drives, etcetera, but since the system was designed for daily use, I have not needed to adjust the points in maybe 20 years.
The voltage on the solenoid is 12 V from the ignition (I) solenoid . The resister on the block brings it down to 7 V feeding to the coil. With 12 volts feeding the dist.

Should I run 12 V from the battery directly to the 12 V on the coil?

Thanks
 

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The Mustang's original yellow top coil was a 1.5 ohm resistance coil left over from the days of 6V electrical systems. When installed in a car with a 12V electrical system a resistor had to be added to prevent "boiling" the oil out of the coil. So Ford added the infamous high resistance Pink wire between the ignition switch and the coil. The Pink wire added another 1.5 ohms resistance to the system. So when the key was in the Run position power to the coil passed through the Pink wire. To aid in starting the engine Ford put the I post on the solenoid. When the key is in the Start position the solenoid is energized and an internal connection is made inside the solenoid that connects the large Bat post on the solenoid to the small I post which sends 12V to the coil for starting assistance. You can run the coil on full 12V for a couple of minutes without damaging the coil.
I don't see a coil in your photos. What kind of coil do you have? Many electronic ignition companies supply 12V coils with enough internal resistance to prevent boiling the oil and no Pink wire or ceramic resistors are needed.
 

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Discussion Starter #18
It’s just a standard 12 V coil bought at AutoZone. Here’s a picture of the resister feeding the coil and the 12 V from the solenoid feeding the module in the distributor.

Can I use a jumper for now to do as a test from the ignition 12v on the solenoid directly to the positive on the coil?

Thank you
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It should say on the side of the coil either "No Resistor Required" or "Use With External Resistor". If you can't find either of those put the leads of a Ohmmeter on the 2 small studs. 1.5 ohm needs a resistor, 3.0 ohms doesn't need a resistor.
 
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