Why won't this f*&$ing thing start?!

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Joined
Oct 23, 2018
Messages
24
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2
Location
NJ
My Car
1971 Mustang Mach 1- 351C

New Carburetor, New battery, New Battery Cables, New Ignition Coil, New distributor, New Distributor cap, new distributor rotor, new spark plugs, new spark plug wires, new 14 Amp fuse in the #4 fuse slot... Why in the f&*k won't this POS start? 

 
Air, fuel and spark is what it takes. Air and fuel mixed in the right proportions, spark at the right time.

Make sure you are getting fuel into the carburetor bowls and fuel squirts out of the nozzles when the throttle is opened. You say new distributor, that leads to several possibilities, the most common errors are not have #1 on the compression stroke and not having the correct firing order in a counterclockwise rotation.

 
Make sure your choke is fully closed when it is cranking...

 
I double, triple quadruple checked the firing order. It's definitely correct. 1-3-7-2-6-5-4-8 counter-clockwise. I double checked my TDC yesterday, it definitely appears to be in the correct position. I can see the fuel squirting into the carb when I pull the throttle back. I even dialed the choke housing back so the choke stays closed. It keeps sounding like it's firing or on the verge of firing then I let go of the key and nothing, just a winding noise as the crankshaft slows to a halt. I attached a timing gun to the cable going from the coil to the distributor when cranking and I see some non-consistent flashing. I stuck the timing gun clamp on plugs 1,2,3 and 4. No light coming from the gun. This left me to believe it was a distributor issue. Took the cap off and had my fiance turn the key. I could see the rotor spinning. Today, I've replaced the coil, rotor and cap. Still nothing.

 
What you haven't told us is what the car has for points/petronix? !    If points, be sure your condenser is good.    If petronix be sure you have 12V (not the reduced voltage factory wire) going to the red for the unit.   

Let's assume all else is correct and start here.....at first I was going to reply "I could start that car in less then 10Mins" BUT figured that doesn't help you.  I THINK you just have to work backwards from where you are.    Your issues are multiple.....if you are only getting voltage to the coil on crank, then of course it won't run when the key lets go  (for now use a dedicated wire to the positive of the coil)    As for "TRYING to start" we can't see how you have the distributor wires clocked , but at some point the vacuum advance will hit the manifold and now allow for more timing!    IF you have to redrop the distributor to get more adjustment DO IT.  

Mark

P.S.  A video tells alot about your work!  IT's how I fix everything on Facebook.

 
What you haven't told us is what the car has for points/petronix? !    If points, be sure your condenser is good.    If petronix be sure you have 12V (not the reduced voltage factory wire) going to the red for the unit.   

Let's assume all else is correct and start here.....at first I was going to reply "I could start that car in less then 10Mins" BUT figured that doesn't help you.  I THINK you just have to work backwards from where you are.    Your issues are multiple.....if you are only getting voltage to the coil on crank, then of course it won't run when the key lets go  (for now use a dedicated wire to the positive of the coil)    As for "TRYING to start" we can't see how you have the distributor wires clocked , but at some point the vacuum advance will hit the manifold and now allow for more timing!    IF you have to redrop the distributor to get more adjustment DO IT.  

Mark

P.S.  A video tells alot about your work!  IT's how I fix everything on Facebook.
I read your posts from Aug.....R U still dealing with this from then??    I read that POP (statement) and then not starting without backfiring and thought " has anyone confirmed this car doesn't still have the plastic timing gear!"    SHOPS don't know everything we do with 40 years experience with engeneering changes!  Before throwing a internet distributor do you think they knew to remove valve cover and watch the valve action in relationship to the distributor?  

Mark

P.S.  You have to do this yourself, you will go broke at $80 per hour and REDOING wrong work if you continue down this path.  Call me. 

 
August was just the point when I got so frustrated I decided I needed the advice of you more seasoned vets on here (You're all amazing). These problems started in June when the car died in the fast lane on i95 in Connecticut. I can confirm it is a points ignition system. I'm getting about 3 volts to my coil with the key in the "on" position. I'm unaware of this plastic timing gear you speak of. Finally how do you check an ignition condenser? I've attached a video of what it currently sounds like.  

-Mike



View attachment IMG_7879.MOV
 
Do you have a factory tach?  It could be that the input transformer to the tach has failed, not allowing current to flow to the coil when in RUN.  If you do have a factory tach, unplug it and jumper the two leads from the underdash harness, then try and start the car.

 
With only 3 volts it's no wonder you're getting inconsistent spark. Disconnect the wire from the positive side of the coil, and with the ignition switch in the run position check the voltage on the wire you just removed from the coil. Without any load on that wire, it should read close to battery voltage. When connected to the coil and the points are closed it should read around 7 or 8 volts. Do you see a little white rectangular ceramic device anywhere near the coil that has wires connected to it? Someone may have mistakenly added a ballast resistor to your system. Check the voltage at that fuse you replaced, make sure you're getting battery voltage there with the key in the run position.

The condenser is that little metal tube next to the points inside the distributor.

The plastic gear is on the front of the camshaft, behind the timing cover, which is behind the water pump. When they wear out the timing chain jumps teeth so the cam and ignition timing goes away. When enough teeth are jumped the valves start hitting the top of the pistons.

 
Success! It is running! It turned out to be the points gap. There wasn’t one! I set it to .017 with my feeler gauge and that seemed to do the trick. Next step is to get the timing adjusted. Thank you all for letting me field my questions here!

 
With only 3 volts it's no wonder you're getting inconsistent spark. Disconnect the wire from the positive side of the coil, and with the ignition switch in the run position check the voltage on the wire you just removed from the coil. Without any load on that wire, it should read close to battery voltage. When connected to the coil and the points are closed it should read around 7 or 8 volts. Do you see a little white rectangular ceramic device anywhere near the coil that has wires connected to it? Someone may have mistakenly added a ballast resistor to your system. Check the voltage at that fuse you replaced, make sure you're getting battery voltage there with the key in the run position.

The condenser is that little metal tube next to the points inside the distributor.

The plastic gear is on the front of the camshaft, behind the timing cover, which is behind the water pump. When they wear out the timing chain jumps teeth so the cam and ignition timing goes away. When enough teeth are jumped the valves start hitting the top of the pistons.
I had a similar issue that Don mentioned/cautioned against with the reduced voltage wire supplying my MSD CDI system. Because of this, my MSD/ignition had insufficient voltage and thus the car would "fall off a cliff" when trying to rev past 5,400 (the engine acted like the valves were floating). Once I ran a dedicated 12V+ via a relay from the battery to the MSD system...It pulls hard all the way up to my rev limiter without any hesitation. 

 
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