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Old 06-13-2010, 03:18 PM   #26
nac593
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Re: major distributor issues!!!

It's a new battery and stays charged. Once i replaced coil and it started. Next time I relaced coil and no start. Replaced modula and started right up. Also, if I find wierd voltage while driving, what is the fix?
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Old 06-13-2010, 03:21 PM   #27
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Re: major distributor issues!!!

bought hei from chevy dealer. battery stays charged. sometimes its the coil.sometimes module. If I have bwierd voltage when driving what is the fix
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Old 06-13-2010, 03:36 PM   #28
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Re: major distributor issues!!!

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Originally Posted by mcbassin View Post
This is a strange situation indeed. I replaced my points setup back in 87 right after I got my 70. Originally I didn't even run a new wire, never had any trouble with it other than changing plugs and wires. Probably put about 50k miles on it daily driving to work. I am still running the original alternator setup.
I wonder if you are getting a spike like stated earlier?

They can still run using the resistor wire but it causes a huge current loss. Its better to change out to 10guage wire
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Old 06-13-2010, 03:47 PM   #29
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Re: major distributor issues!!!

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Originally Posted by mbgmike View Post
They can still run using the resistor wire but it causes a huge current loss. Its better to change out to 10guage wire
Totally agree with changing to the 10g wire, I didn't know at the time of the upgrade, (young and ignorant) just tried it and it worked for about 12 years. I wouldn't do it again, it's too easy to change out with bigger wire.

Last edited by mcbassin; 06-13-2010 at 03:47 PM.
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Old 06-13-2010, 03:54 PM   #30
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Re: major distributor issues!!!

My 68 went this way. The main power wire went from the batt to the horn relay and from there to the power supply for the cab. I installed a power distribution point (big power stud covered in red plastic covers off of a '03 GM something.) on the firewall and supplied it with power from the batt with a 6ga red wire. I then took the #2 small red wire off the internally regulated alternator two prong plug and ran it to the power dist point so that it would sense the voltage at this point. Then the cab, the ignition, and everything else that needs power gets it from this power point. The big red wire from the alternator runs down to the starter end of the battery cable. This was run this way to isolate the alternator from the rest of the system to minimize speaker buzz in the two-way radio. The battery stands between the system and the alternator.

With it done like this, the voltage at the power point never varies no matter the load. With your situation this would shorten up the wire supplying the ignition and stabilize the voltage supply to your ignition system.

Sounds complicated but it works and it's really simple.
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Old 06-13-2010, 03:55 PM   #31
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Re: major distributor issues!!!

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Originally Posted by nac593 View Post
bought hei from chevy dealer. battery stays charged. sometimes its the coil.sometimes module. If I have bwierd voltage when driving what is the fix

I would take it to a good mechanics shop to see what its doing. Get them to put it on the scope and get a waveform on it to see. It could be a capacitor it could be a lot of things. HEI can be real complicated at times. Its hard enough to do it with the correct equipment let alone without it.
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Old 06-13-2010, 05:19 PM   #32
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Re: major distributor issues!!!

I ran a new 10 ga. wire from fuse panel. keyed on source
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Old 06-13-2010, 05:25 PM   #33
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Re: major distributor issues!!!

How about the pick-up coil?

It's located under the centrifigal advance. You can test it without removing it... check in your service manual on how to check it. If it's bad, you have to pull the shaft out of the unit to replace it. They are a little spendy to replace. But, might be worth testing it just to rule it out.

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Old 06-13-2010, 06:48 PM   #34
Mr Chevorlet
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Re: major distributor issues!!!

Could you smack the top of the dissy with something, I know this wont solve anything but sounds like the same problem i had on a 69 truck that i had put an HEI in and after replacing things time and time again, for some reason i smacked the top of it dissy and it started right up. So i told my daughter when it wont start to smack the top of the dist. Never did find the problem we finally sold that one. but it did it a couple of times a week.
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Old 06-17-2010, 06:40 PM   #35
nac593
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Re: major distributor issues!!!

I replaced the ignition module and it started right up. Now how do I check voltage while driving? Do I crimp another wire at the distributor connection or can I just check it at the fuse panel since thats where the wire comes from ?
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Old 06-17-2010, 10:17 PM   #36
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Re: major distributor issues!!!

i've run pertronix's and i am happier with points
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Old 06-18-2010, 02:45 AM   #37
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Re: major distributor issues!!!

Just use alligator clips and clip on as close to the HEI as possible. Duct tape the voltmeter to the windshield where you, or better yet a friend, can see it.

Ok, if your wire from the fuse panel is at least 12ga you can check it at the fuse panel.

Drive it with all accessories on and do some stop and go and some at speed. The volts should never vary more than half a volt, even when you shut the accessories off at speed, there should be no spike. Should be 13.8 to 14.3. Don't trust your memory here, write it down.
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1968 C10 (newly acquired)
1967 Checker Marathon (waiting for paint)
1968 C50 Service Truck (resting in peace for now)

I need another project like I need another hole in my head!!!

Last edited by Captain Underdog; 06-18-2010 at 03:05 AM.
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