Dumbfounded. 340 will not start.

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VonCramp

VonCramp

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I recently posted a thread about this but I left out some details that may be of importance. I recently purchased a 1969 Barracuda. It is originally a factory big block 4-speed car. It now has a 340 with a 18 spline a-body 4-speed(not an easy find.) I recently installed the 340 and got the car running beautifully. I used a Mallory Unilte distributor with all new parts. The car quit running after 3 days. I then bought an HEI style off of eBay and it ran great for three days and quit. The ignition switch and 340 motor were both pulled from my 68 Barracuda that was hit hard in the rear and totaled. Basically, I am getting spark at the number one plug with the same HEI distributor still installed. Motor is getting fuel. I verified this by looking into the carb and see the fuel sqirt from the shooters. I have fuel and spark but does not run. No ballast resistor is needed for the distributor. The spark does look weak because it is more of a pink than a blue spark. The Mallory promaster coil was used with both distributors. I have the hei distributor wired from the resistor plug blue wires side. The brown wire side is not connected to anything. I am at a total loss. Out of money and patience.
 
VonCramp said:
I recently posted a thread about this but I left out some details that may be of importance. I recently purchased a 1969 Barracuda. It is originally a factory big block 4-speed car. It now has a 340 with a 18 spline a-body 4-speed(not an easy find.) I recently installed the 340 and got the car running beautifully. I used a Mallory Unilte distributor with all new parts. The car quit running after 3 days. I then bought an HEI style off of eBay and it ran great for three days and quit. The ignition switch and 340 motor were both pulled from my 68 Barracuda that was hit hard in the rear and totaled. Basically, I am getting spark at the number one plug with the same HEI distributor still installed. Motor is getting fuel. I verified this by looking into the carb and see the fuel sqirt from the shooters. I have fuel and spark but does not run. No ballast resistor is needed for the distributor. The spark does look weak because it is more of a pink than a blue spark. The Mallory promaster coil was used with both distributors. I have the hei distributor wired from the resistor plug blue wires side. The brown wire side is not connected to anything. I am at a total loss. Out of money and patience.
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From my experiences if your spark in't a nice hot blue spark it wont run, I would check you coil and make sure its actually putting out what its supposed to.
 
do not run that dist/coil from the old ballast supply (blue)(etc) wire. I garuntee there is too much resistance in that circuit and the voltaqge is not high enough. I would wire in a relay and run something off the batt. There is too much resistance in the old wiring harnesses, especially after this much time. make sure you got a good alt too as you will need one.
 
I will do that. Could the coil have been going bad with the Unilite and finally just crapped out with the HEI? Just weird that I am still getting a spark at all. One thing I did experience is I got the crap shocked out of me by the cap even though the car wasn't running or cranking. The key was on though.
 
yeah, the coil could do that to ya if it was cracked up near the top of it. A close inspection of the coil would b good idea. (like if your leaning on the fender and the coil has a hair line crack, It might think "hey that dude looks like a good ground path") yeah I could see that happening. Might be a good alternative to coffee in the morn, haha. (jus kiddin)
 
omahamoparguy said:
yeah, the coil could do that to ya if it was cracked up near the top of it. A close inspection of the coil would b good idea. (like if your leaning on the fender and the coil has a hair line crack, It might think "hey that dude looks like a good ground path") yeah I could see that happening. Might be a good alternative to coffee in the morn, haha. (jus kiddin)
Click to expand...
Getting shocked is really annoying because even though it last a brief moment you keep feeling it after the shock is long gone. BTW I was on the driver's side and coil is mounted passenger side. I was touching cap and leaning on car. It would still shock me even though the car isn't running or cranking? I am really starting to think this car just hates me and wants me broke and dead.
 
You must use the brown wire (IGN2) also. It is the only one that has 12 V ignition while cranking the starter (key in "start" position). Jumper it to the blue wire (IGN1). You can use a short jumper cable w/ dual male spades or there is a single male-male spade to clip them together neatly. I made that mistake when I got rid of the ballast in my Dart. No matter how long I cranked, no fire, but as I released the starter it sometimes started.

How did you verify a spark? I doubt you saw anything while cranking with the brown wire open. If not totally out of funds, buy a $4 in-line spark tester (Harbor Freight). Just because it sparks in the air doesn't mean it sparks at cylinder pressure.
 
My first suspect would be POOR SUPPLY VOLTAGE. Even if wired correctly, problems in the bulkhead connector, ignition switch connector or switch itself could be a problem.

1---CHECK whatever needs to be grounded. If the "box" is the ground, clean it, use a jumper ground wire, use star washers

2---CHECK the supply voltage CRITICALLY. With engine off, but key in run, supply voltage should be "same as battery." Not 1/2 volt below, or one volt low, but SAME AS within a couple or three tenths of a volt

3--To be sure, BYPASS or disconnect factory wiring, use a large such as no14 clip lead, and "hot wire" the ignition direct to battery

4--Coils can go bad AT ANY TIME even new out of the box. Swap a known good coil

5--Coil WIRES can go bad, as well as carbon tracked/ cracked or otherwise conductive rotors and caps. I once "knew" a rotor that at first glance looked fine. It had a "bad?" spot right under the rotor button that was carbonized and would conduct almost all the spark straight from the button to the top of the dist. shaft!!!!
 
BillGrissom said:
You must use the brown wire (IGN2) also. It is the only one that has 12 V ignition while cranking the starter (key in "start" position). Jumper it to the blue wire (IGN1). You can use a short jumper cable w/ dual male spades or there is a single male-male spade to clip them together neatly. I made that mistake when I got rid of the ballast in my Dart. No matter how long I cranked, no fire, but as I released the starter it sometimes started.

How did you verify a spark? I doubt you saw anything while cranking with the brown wire open. If not totally out of funds, buy a $4 in-line spark tester (Harbor Freight). Just because it sparks in the air doesn't mean it sparks at cylinder pressure.
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I verified it with a timing light and I also pulled the #1 plug out and cranked the motor over while watching it. Are you saying that I connect both plugs together that would normally attach to the resistor?
 
67Dart273 said:
My first suspect would be POOR SUPPLY VOLTAGE. Even if wired correctly, problems in the bulkhead connector, ignition switch connector or switch itself could be a problem.

1---CHECK whatever needs to be grounded. If the "box" is the ground, clean it, use a jumper ground wire, use star washers

2---CHECK the supply voltage CRITICALLY. With engine off, but key in run, supply voltage should be "same as battery." Not 1/2 volt below, or one volt low, but SAME AS within a couple or three tenths of a volt

3--To be sure, BYPASS or disconnect factory wiring, use a large such as no14 clip lead, and "hot wire" the ignition direct to battery

4--Coils can go bad AT ANY TIME even new out of the box. Swap a known good coil

5--Coil WIRES can go bad, as well as carbon tracked/ cracked or otherwise conductive rotors and caps. I once "knew" a rotor that at first glance looked fine. It had a "bad?" spot right under the rotor button that was carbonized and would conduct almost all the spark straight from the button to the top of the dist. shaft!!!!
Click to expand...
Thanks for taking the time to reply to my posts. I will do everything you have suggested. Can I use my start relay as a good source for a new distributor wire feed? Seems like it would be a clean installation point.
 
You can, if you do, use it to also feed the regulator IGN terminal. It is quite common in these old cars for the bulkhead connector and other points in the harness to be a problem.

Read this Mad article for insight:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

The diagram down that page shows clearly the problem points in the harness:

The path (follow the diagram)

is from the battery (red wire) --fuse link-- bulkhead connector -- ammeter-- through the meter -- out the ammeter -- to the in harness welded splice -- branch off to ignition switch connector (not pictured) -- through the ignition switch -- back out the switch connector -- back out the bulkhead connector on the "igntion run" or "IGN1" buss, which feeds

ignition run voltage to the "key" side of the ballast,

the regulator IGN terminal

On 70 and later cars, it also feeds a few other things, the alternator blue field lead, electric choke if used, and some smog doo dads on some cars.

Both the red and black bulkhead connector terminals can develop problems as described in the MAD article, but the blue "ignition run" terminal can, also.



amp-ga18.jpg
 
67Dart273 said:
You can, if you do, use it to also feed the regulator IGN terminal. It is quite common in these old cars for the bulkhead connector and other points in the harness to be a problem.

Read this Mad article for insight:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

The diagram down that page shows clearly the problem points in the harness:

The path (follow the diagram)

is from the battery (red wire) --fuse link-- bulkhead connector -- ammeter-- through the meter -- out the ammeter -- to the in harness welded splice -- branch off to ignition switch connector (not pictured) -- through the ignition switch -- back out the switch connector -- back out the bulkhead connector on the "igntion run" or "IGN1" buss, which feeds

ignition run voltage to the "key" side of the ballast,

the regulator IGN terminal

On 70 and later cars, it also feeds a few other things, the alternator blue field lead, electric choke if used, and some smog doo dads on some cars.

Both the red and black bulkhead connector terminals can develop problems as described in the MAD article, but the blue "ignition run" terminal can, also.



amp-ga18.jpg
Click to expand...
Awesome diagram! Should help me a lot. In order to further simplify things I purchased a Powermaster one wire alternator. Correct me if I am wrong, but I can still use my original hot lead to alternator on the one wire, right?
 
Yes, but read that article throughly. Especially if your powermaster is fairly high output, IE over 50A, and even if not, the original bulkhead connector/ other wiring can be damaged. All that is in the Mad article.
 
VonCramp said:
I verified it with a timing light and I also pulled the #1 plug out and cranked the motor over while watching it. Are you saying that I connect both plugs together that would normally attach to the resistor?
Click to expand...

Yes, you need to connect the 2 terminals together that normally attach to the ballast resistor (4 terminals in early design). Since you were getting a spark while cranking, I wonder if somebody connected IGN1 (blue) and IGN2 (brn) together in the cabin. Check around the key switch and bulkhead area, or use a multimeter to see if they are connected (<5 ohm) with the key off.
 
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