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Discussion Starter · #1 ·
I'm working on starting my 1966 Mustang after it has been sitting for several years. It has a 289 v8 and automatic transmission. I've gotten a new starter, starter solenoid, voltage regulator, points, rotor, spark plug wires, and plugs. It cranks over just fine, however, I haven't been able to turn it over long enough to fire up the engine before the ground wire from the engine block to firewall melts.

Hopefully, I can get help from someone who knows wiring very well. I personally am not good at wiring at all and am very confused.
 

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Your starter is grounding through the small diameter wire from the engine to the firewall which is overloading that small wire. Your starter should be grounding through the Negative battery cable. The Negative battery cable should be attached to the lower right front corner of the engine block. There is a hole drilled and tapped in the block specifically for the Negative battery cable to attach to. Where is your Negative battery cable attached now?
 

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Discussion Starter · #3 ·
Your starter is grounding through the small diameter wire from the engine to the firewall which is overloading that small wire. Your starter should be grounding through the Negative battery cable. The Negative battery cable should be attached to the lower right front corner of the engine block. There is a hole drilled and tapped in the block specifically for the Negative battery cable to attach to. Where is your Negative battery cable attached now?
I currently have it grounded to the front radiator support. I only have a short battery cable as of right now but ill see if I can get a longer one sometime this weekend.
 

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I currently have it grounded to the front radiator support. I only have a short battery cable as of right now but ill see if I can get a longer one sometime this weekend.
...just how good is the quality of the barttery? All are not created equal. Put a charger on it, in the meantime.
 

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Awhtx nailed it. You need a negative battery cable, equal in gauge to the starter cable, connected to the engine block. There is a boss for a bolt just above the oil pan rail on the front passenger side for this purpose.
 

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This post is actually helpful to me. I have my negative cable grounded to the head but it's right behind the coil so it's a pain to get to. Now I know there is a better location.
 

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Discussion Starter · #8 ·
Your starter is grounding through the small diameter wire from the engine to the firewall which is overloading that small wire. Your starter should be grounding through the Negative battery cable. The Negative battery cable should be attached to the lower right front corner of the engine block. There is a hole drilled and tapped in the block specifically for the Negative battery cable to attach to. Where is your Negative battery cable attached now?
I got a new cable for the battery and good news is, the block to the firewall ground isn't melting anymore. However, the battery to block ground is getting warm and starting to melt.

Any Ideas on that?
 

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Assuming you have a quality ground cable that's sized correctly. With the new cable, is the starter spinning vigorously? If not, what is the history of the starter?
 

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Discussion Starter · #10 ·
Assuming you have a quality ground cable that's sized correctly. With the new cable, is the starter spinning vigorously? If not, what is the history of the starter?
The starter is brand new and spinning just fine. I'm waiting for the battery to charge up again right now cause I was trying to start it today and drained it. Granted I was cranking for like 3 minutes, not nonstop obviously. But it the engine was sputtering like it was about to start up.
 

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Ok good. Sorry, I missed this in your opener. Once the battery is fully charged, don't go back to cranking until you perform a few diagnostics, cause, apparently, it aint happy about firing. If this is a "points" distributor, insure the settings are correct and all is as it should be with the wires, rotor, can and plugs. Have you rotated the distributor at any point? Insure the rotor is pointing to #1 at TDC. Are you seeing fuel stream from the squirters, when you manually actuate the linkage?
If the engine is tuned properly, it needs, only, to be cranked in short bursts of a few seconds each. To crank longer, only serves to drain the battery and overheat the starter.
 

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Discussion Starter · #12 ·
Ok good. Sorry, I missed this in your opener. Once the battery is fully charged, don't go back to cranking until you perform a few diagnostics, cause, apparently, it aint happy about firing. If this is a "points" distributor, insure the settings are correct and all is as it should be with the wires, rotor, can and plugs. Have you rotated the distributor at any point? Insure the rotor is pointing to #1 at TDC. Are you seeing fuel stream from the squirters, when you manually actuate the linkage?
If the engine is tuned properly, it needs, only, to be cranked in short bursts of a few seconds each. To crank longer, only serves to drain the battery and overheat the starter.
I did rotate the distributor to "advance" the timing. there is a stream so all is good there. i haven't tried tuning anything beings it been probably 20 somthin' years since it last ran. And how would I check if the rotor is pointing to #1 at TDC?
 

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I did rotate the distributor to "advance" the timing. there is a stream so all is good there. i haven't tried tuning anything beings it been probably 20 somthin' years since it last ran. And how would I check if the rotor is pointing to #1 at TDC?
Ok, when your were cranking, was there any indication the engine was attempting to "fire"?
I see your replaced a bunch of components.
Have your verified the coil output to the distributor or there is a healthy spark at the plug?

"And how would I check if the rotor is pointing to #1 at TDC?
Remove the cap, rotate the engine by hand or with a socket on the crank bolt. Some folks remove the plugs to make it much easier. Some folks will manually check the timing before installing new plugs, if it is suspect.
In ny event, rotate (CW) the crank towards "0" while watching the rotor rotate CCW. When it reaches #1 (pointing approx.at 1:00 O'CLOCK) where is the timing mark? It should be very near TDC "0" on the balancer.
 

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I got a new cable for the battery and good news is, the block to the firewall ground isn't melting anymore. However, the battery to block ground is getting warm and starting to melt.

Any Ideas on that?
What gauge wire is that ground? Did you get a high quality piece at a battery shop?
 

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Discussion Starter · #15 ·
Ok, when your were cranking, was there any indication the engine was attempting to "fire"?
I see your replaced a bunch of components.
Have your verified the coil output to the distributor or there is a healthy spark at the plug?

"And how would I check if the rotor is pointing to #1 at TDC?
Remove the cap, rotate the engine by hand or with a socket on the crank bolt. Some folks remove the plugs to make it much easier. Some folks will manually check the timing before installing new plugs, if it is suspect.
In ny event, rotate (CW) the crank towards "0" while watching the rotor rotate CCW. When it reaches #1 (pointing approx.at 1:00 O'CLOCK) where is the timing mark? It should be very near TDC "0" on the balancer.
I was able to get the engine to fire up earlier today and am no longer having issues with the wire melting. Turns out that I was cranking the engine for too long at a time. I also found that I didn't have the correct firing order. I had plugged the wires the same way as the original wires were plugged not thinking to check the firing order. right after did that, it fired right up.

Anyways, THANK YOU!
 
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