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Discussion Starter #61
Beginning to think my problem is in my wiring, as when it ran fine before was before I wrapped and bundled to make it look pretty, and the battery is on the passenger firewall now. So I have a chevy 1 wire alternator wire running across there as well as all the MSD and other stuff bundled into about a 1" group.

Perhaps the coil fix was a part of it, but this might be another big part as I have read that alternator is the worst for interferance. That, the plug wires in parallel on the 5 &7 and the dizzy and coil and alt wire in that bundle, even if they're not next to each other.

So I'll go through the valve adjustments looking for any gremlins and then tear apart my sweet wiring job. If I go with that other dizzy I'll need to pull all the MSD wiring out anyway. so I'll get it back to ugly and seperate and see what happens.

Edit: and also adjust the idle air/fuel mix

Might also note the alternator wire is in that bundle as is the power main for the car, and I have 3 electric fans on it.
 

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Your wiring isn't going to make a whistling sound. I'd first find what you know is a problem.
 

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Your wiring isn't going to make a whistling sound. I'd first find what you know is a problem.
Probably the alternator wailing in protest.

Actually if not done yet, the OP needs to get a voltmeter on there. Often 1 wire alternators are slow to react to imposed loads especially at low rpm's. If those fans are running and the alternator not delivering the B+ voltage is going to sink under the expected 12.5 pretty fast.

And I agree whistling sounds usually lead to an air leak into the intake system, he needs to chase this down.

Bogie
 

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Discussion Starter #64
Probably the alternator wailing in protest.

Actually if not done yet, the OP needs to get a voltmeter on there. Often 1 wire alternators are slow to react to imposed loads especially at low rpm's. If those fans are running and the alternator not delivering the B+ voltage is going to sink under the expected 12.5 pretty fast.

And I agree whistling sounds usually lead to an air leak into the intake system, he needs to chase this down.

Bogie
no whistling sound, not sure where that came from. sputtering is the last it was doing, but not a kind I have experienced before.....more like a spark issue. I do have a voltage guage in the car and it runs about 14 when running. I'd know a vacuum leak.
 

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rich...not gummed up, but pretty rich

How gummed up are the plugs? Rich mixtures can be a struggle to set on fire. You hesitations but not with backfires like a lean mixture.



Modern plugs once fouled are trashed and need to be replaced.


Rich mixtures come out of too much fuel or too much time on choke which causes to much fuel to be pulled in, you gotta solve the cause.


Bogie
 

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Discussion Starter #71
update: got a TDC tool and went back to scratch. The timing mark on the HB is off by an inch or so. so the dizzy was 1 notch off. made a new mark, dizzy set right and going to go back through the valves before buttoning it up and rerouting some wires.
 

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May want to replace the damper, if it slipped it just may fall off in the near future.
 

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Discussion Starter #73
sorry to be a bother, but I bought the distributor suggested. It says positive to the coil, and negative to the coil. thats it. Should I ground the coil?
 

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sorry to be a bother, but I bought the distributor suggested. It says positive to the coil, and negative to the coil. thats it. Should I ground the coil?
No, only the negative from the distributor should be connected to the coil negative post, the coil should not be grounded to engine ground.
Only other wire connected to the negative post on the coil would be the tach trigger wire
 

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sorry to be a bother, but I bought the distributor suggested. It says positive to the coil, and negative to the coil. thats it. Should I ground the coil?

The coil grounds through the negative connection with the distributor. The distributor is timing the coil ground to the firing needs of the engine.



Bring the B+ voltage to the coil, this if you come off the ignition switch needs to be the ignition wire that is hot during start and a 12 volt B+ from the run terminal if it is wired that way which is more common to older points ignitions where the RUN terminal either used a resistive wire or a resistor to deliver 6 to 9 volts to the coil. While the start terminal supplied whatever B+ was with the starter running usually about 8 to 10 volts. With later electronic systems the start switch connects the start and run terminal together so there is always B+ voltage fed to the coil. So you need to know how your wiring is accomplished to be sure you bring B+ voltage to the coil for both start and run with electronic ignitions.



In the end you need to put the 12 volt B+ voltage from the key switch onto the positive terminal of the coil. On this same terminal will connect the usually red wire that is the B+ supply to the distributor, this runs the electronics within the distributor. The negative wire (usually black) is the switched by the distributor connection to the coil, it connects to the coil's negative terminal.



The distributor is switching the primary coil winding to ground or not in time to the engine's spark requirements. When ground happens and current flows through the primary winding a magnetic field builds in the core. There is a sensor in the distributor that is reading timed pulses, these control a transistor that does the coil switching. When the primary winding is shut off by the transistor switch, the magnetic field of the core collapses, when that happens the many more and finer windings of the secondary coil discharge a high voltage into the central terminal of the distributor cap to be sent to the selected cylinder's spark plug. For a points ignition the cam in the distributor is timing the closing and opening of the point switch to accomplish the building of the magnetic field of the primary coil and subsequent collapse of that field to generate the high voltage of the secondary coil.


There are deeper complications of what's going on but that's the working summary. Your wiring is simply to allow this end. If you grounded the coil there would be no interruption of current in the primary winding thus except when turning the key switch OFF there would be no high voltage generated.



Bogie
 

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Discussion Starter #76
So, I finally got it running again with the distributor you guys recommended. thank you.

It's a project car, so I moved on to a dozen other things finishing up and had to rewire the thing because the battery has been moved from drivers side to passenger side and all power cables going across engine.

I have it wired now for both, this ebay distributor as well as my MSD 6AL and pro billit distributor, but I'll send of the msd box to check and see if it's good. For now I'll leave this dizzy in, as the engine is still breaking in and I drove it for about 30 minutes.

It has a little stumble when getting on it about mid rpm range, but pretty sure it's carb related and will focus on that, but for now I'm gonna keep the timing as it is. 10 BTDC and running and starting pretting good.

There's a lot of info out there to confuse someone when it's their 1st SBC build, including a summit video saying btdc is actually atdc!!!

Thank you guys.
 
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