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LX301 HEI Control Module
https://slantsix.org/forum/viewtopic.php?t=51145		 Page 11 of 15
Author:  emsvitil [ Tue Mar 19, 2013 5:45 pm ]
Post subject: 
What's the voltage at the battery when cold and cranking?

What's the voltage at the coil when cold and cranking?


Voltage may be too low for the ignition when cold.

When it doesn't start, put a 50 amp starting charger on the + of the coil and see if it helps (don't run for long like that).
Author:  JCAllison [ Wed Mar 20, 2013 5:06 am ]
Post subject: 
Quote:
What's the voltage at the battery when cold and cranking?
Hey Mr. E,
Don't know. But, Lorrie has a BRAND NEW NAPA Legend 75 Battery.
Quote:
What's the voltage at the coil when cold and cranking?
Don't know. But, it is about .05 of a volt less than the whatever the Battery has.
Quote:
Voltage may be too low for the ignition when cold.
If that is the case, then this whole exercise is hopeless because the Legend 75 Battery is the BIGGEST Battery that could be acquired.
Quote:
When it doesn't start, put a 50 amp starting charger on the + of the coil and see if it helps (don't run for long like that).
Haven't access to a 50 Amp Starting Charger.

Am in the process of putting the Dash Panel back in. Ran into a strange situation last evening. Found a wire that didn't seem to have any rhyme or reason. Got out the Stewart Warner Fuel Gauge Instruction Sheet, and found that it is not necessary. And I don't remember WHY it was put where it was put. It can just be deleted and everything will be fine. I sometimes wonder at some of the things that I do!

Anyway, thanks for the comments and suggestions.

Hope you have a GREAT day.

JC
Author:  JCAllison [ Wed Mar 20, 2013 6:16 am ]
Post subject: 
Hey All,
Have three specific question:

1. With the Test Light connected to the "-" Terminal of the FD784X Ignition Coil, with the Run Switch ON, and the Probe of the Test Light on the "B" Terminal of the NAPA Echlin TP45 Control Module: Should the Test Light be ON?

2. With the Test Light connected to the "-" Terminal of the FD784 Ignition Coil, with the Run Switch ON, and the Probe of the Test Light on the B"Terminal of the NAPA Echlin TP45 Control Module: Should the Test Light "blink" when cranking?

The situation with Lorrie is that in the first question's set up, the Test Light is ON steady.

The situation with Lorrie is that in the second question's set up, the Test Light does NOT "blink".

Would not THAT indicate that the FD784 Ignition Coil is shorted?

Thanks in advance for the answers.

JC
Author:  Charrlie_S [ Wed Mar 20, 2013 7:06 am ]
Post subject: 
1)Clip test lite to ground.
2) ign on, probe to positive of ign coil, lite on
3) ign on, probe to negative of ign coil, lite on (if lite off either coil is open or module/wire is shorted.
4) engine cranking, probe to negative of ign coil, lite should blink. If not blinking, module is not triggering coil. (either bad module or no trigger from distributer)
Author:  JCAllison [ Wed Mar 20, 2013 8:58 am ]
Post subject: 
Quote:
Hey Charrlie,
Am just about to finish the re-installation of Lorrie's Dash Panel. As soon as it is all back in will be doing YOUR diagnostic tests.
Quote:
1) Clip test lite to ground.
Alright. Will do this, and report back.
Quote:
2) ign on, probe to positive of ign coil, lite on.
Alright. Will do this, and report back.
Quote:
3) ign on, probe to negative of ign coil, lite on (if lite off either coil is open or module/wire is shorted.
Alright. Will do this, and report back.
Quote:
4) engine cranking, probe to negative of ign coil, lite should blink. If not blinking, module is not triggering coil. (either bad module or no trigger from distributor)
Alright. Will do this, and report back.

Thanks for the list of procedures.

JC
Author:  Aggressive Ted [ Wed Mar 20, 2013 12:00 pm ]
Post subject: 
Quote:
Have found an FD784X NEW for under $40.00. May just go ahead and spring for that.
Is that a round canister style coil or an HEI style?

On the plugs, I have a 1980 engine in there now and 76 head on my high compression engine. Both use the peanut style plugs. No drool tubes.
Quote:
How long did it take to get it to this condition?
About a year and half....
Author:  JCAllison [ Wed Mar 20, 2013 12:25 pm ]
Post subject: 
Quote:
Is that a round canister style coil or an HEI style?
Hey Ted,
It is NOT a "round canister style". It IS an HEI style, like the one on YOUR vehicle.

The FD784X is the Blue Ignition Coil pictured in Daniel's post about the HEI Conversion.
Quote:
On the plugs, I have a 1980 engine in there now and 76 head on my high compression engine. Both use the peanut style plugs. No drool tubes.
"Peanut style plugs"? Drool tubes"? By "drool tubes", are you talking about the Aluminum Tubes, into which the Spark Plugs fit?
Quote:
About a year and half....
You're pretty good and fast at this kind of thing.

I've been working on Lorrie for over four years, but then again, I'm slower than molasses in January, and there has been a whole bunch of things done to her.

As of this afternoon, Lorrie's Dash is all reinstalled. Am taking a break.

Am going to go out and hook up the "-" Battery Cable and test the Head Lights, Brights, Brights Indicator Light, Instrument Lights, Tail Lights, Brake Lights, Turn Signals, Flashers, Horn, Windshield Wipers, Fuel Gauge, Run Switch, and Start Switch.

And if everything works, it will once again be time to start chasing the gremlin/s that are keeping Lorrie from starting&running.

I now have no choice in the matter because just yesterday it was found that the Lower Ball Joints in Ms. American's Front Suspension are in need of replacement.

And I don't have the budge to get the parts and either have it done, or do it myself.

So Lorrie is going to have to be gotten up&running or the cats and myself are going to starve!

What I'm trying to find out is what would cause the Ignition Coil to go bad, if indeed it has gone bad?

Could the two Mechanical Voltage Regulators that were putting out over 18 and almost 17 Volts have caused the Ignition Coil's demise? I know it took out the Control Module, but it has been replaced. And Lorrie is now running an Electronic Voltage Regulator that the last time she was running was allowing 13.3 to 14.1 Volts to go to the Battery.

Hopefully there will be some way to get Lorrie to Start&Run. Am nearing desperation.

Hope you have a GREAT day.

JC
Author:  Aggressive Ted [ Wed Mar 20, 2013 2:31 pm ]
Post subject: 
JC,
Quote:
You're pretty good and fast at this kind of thing.
I keep a list in my pocket of things to do.....next is a bigger heat shield, got all the material, then the air/oil separator plumbed into the PCV system, then a bigger air dam (the prototype settles the car down), install the HEI module, install the new Nipon Denso alternator, polish the 7" aluminum rims, more body work, install stainless exhaust tip, etc....
Quote:
What I'm trying to find out is what would cause the Ignition Coil to go bad, if indeed it has gone bad?
Take it with you to the parts store, hopefully they will warranty it. Take your sales slip with you. Our Black Diamond Auto Parts warranties all their products so it is not a problem! Could be just poor quality and a pinched/shorted winding. The wire on my coil is pretty good size.
Quote:
Drool tubes
Yes, the aluminum tubes......I have had enough engines with those drool tubes.....over the years. The 1976 to 80 head goes a long way to keeping the engine nice and clean. The old blocks are fine, I prefer installing the newer style heads and valve covers. The PCV system seals and works much better.

Hope all goes well. Don't give up!
Author:  JCAllison [ Wed Mar 20, 2013 3:00 pm ]
Post subject: 
Quote:
JC, Take it with you to the parts store, hopefully they will warranty it. Take your sales slip with you.
Hey Ted,
Alas, I did not buy the coil, and it was not gotten from a local Auto Parts Store. It was purchase off of the Internet by a fellow in Florida who sent to to me.

Also, I notice that I have been using the wrong parts number. It is a Standard Blue Streak FD478X.

Quote:
Our Black Diamond Auto Parts warranties all their products so it is not a problem! Could be just poor quality and a pinched/shorted winding.
Could the fact that the OLD Mechanical Voltage Regulator was putting out over 18 Volts have started the FD478X Ignition Coil on the way to dying?

Am looking for the REASON that the Ignition Coil would have gone bad. The Standard Blue Streak FD478X was listed by Daniel Stern as the "premium" unit. And would not think that he would have done that if they were of questionable quality.

Just called NAPA and they have a replacement for this coil for only $33.00 plus tax, but it is NOT a FD478X.

I might just go ahead and get it to see if in fact it is the Ignition Coil that is the gremlin in this whole situation.

Whaddaya think?
Quote:
The wire on my coil is pretty good size.
That's Pertronix unit? What do THEY cost?
Quote:
Yes, the aluminum tubes......I have had enough engines with those drool tubes.....over the years. The 1976 to 80 head goes a long way to keeping the engine nice and clean.
Had never heard those Tubes called "drool tubes", but the name certainly fits.
Quote:
The old blocks are fine, I prefer installing the newer style heads and valve covers. The PCV system seals and works much better.
For you guys who do more of this than do I, you develop preferences. I'm stuck with what I have and that is fine with me. I just need Lorrie up&running reliably, because Ms. American has become un-drivable because of bad Lower Ball Joints on her Front Suspension.
Quote:
Hope all goes well. Don't give up!
I apparently CAN'T give up now.

JC
Author:  JCAllison [ Wed Mar 20, 2013 3:34 pm ]
Post subject: 
Quote:
1)Clip test lite to ground.
Hey Charrlie,
Just went out and did this series of test.
Quote:
2) ign on, probe to positive of ign coil, lite on
The Light came on.
Quote:
3) ign on, probe to negative of ign coil, lite on (if lite off either coil is open or module/wire is shorted.
The Light came on. So the Coil is NOT open. and the Module/Wire is NOT Shorted.
Quote:
4) engine cranking, probe to negative of ign coil, lite should blink.
Light came on, but did NOT blink. It seemed to dim a bit while cranking.
Quote:
If not blinking, module is not triggering coil. (either bad module or no trigger from distributor)
Alright. The Light did NOT Blink. So now we NOW have either a BAD Module (It is a NAPA Echlin TP45, only days old, and has not been overloaded in any way, as it has never been supplied with electricity with other than a NEW Electronic Voltage Regulator putting out no more than 14.1 Volts), or we have a Distributor that is NOT triggering the Control Module.

Ran a resistance test of the Distributor. It is 277 Ohm.

Ran a resistance test between the "+" and "-" of the Ignition Coil. It had .7 Ohms Resistance.

Ran a resistance test between the "+" of the Ignition Coil and the Ignition Coil Output Post, and it was OF = Infinity.

Ran a resistance test between the "-" of the Ignition Coil and the Ignition Coil Output Post, and it was OF = Infinity.

The Ignition Coil is toast?

JC
Author:  emsvitil [ Wed Mar 20, 2013 3:58 pm ]
Post subject: 
Bad wiring, bad connections can lower voltage, doesn't depend on new battery.

My thinking is as follows (sorry didn't think of this till now)

When cold, a battery doesn't produce as much volts, and with either bad wires or connections, the voltage may drop below a threshold that produces a spark. (plus a cold engine has more cranking resistance)

Pulling the wire and checking for a spark might not be enough of a test. It takes less energy to jump to ground than to jump the spark plug gap because of the cylinder compression. So it may look like you have sparks, when you really don't.


What I remembered was when my motorcycle battery was getting old. The bike would crank, but not start. Then it would just catch and run right after I released the starter. Evidently the voltage went up because the starter was off, and then I had a spark for that last bit of cranking.

I found that I was below 9 volts at the ignition module due the the convoluted wiring (and small gauge wire used) when cranking.

I fixed the problem by rewiring to the ignition module with a relay so that the ignition module had as many volts as possible.

See this:
http://www.cranecams.com/uploads/instru ... 003000.pdf


If you can temporarily supply the ignition module and coil with it's own power supply, you can see if voltage drop is your problem...


Or you can do what I did with my old Mazda RX2........ I used some starter relays and an extra battery so that when starting there was 24volts supplied to the starter.......
Author:  DusterIdiot [ Wed Mar 20, 2013 4:19 pm ]
Post subject:  Lol..
Quote:
Or you can do what I did with my old Mazda RX2........ I used some starter relays and an extra battery so that when starting there was 24volts supplied to the starter.......
That's an old demo derby trick so you can get it lit again before you get wolloped. The bad part is the standard mopar big block starter doesn't take kindly to that kind of voltage and usually goes belly up after a couple of heats...

-D.Idiot
Author:  Aggressive Ted [ Wed Mar 20, 2013 5:58 pm ]
Post subject: 
Quote:
Could the fact that the OLD Mechanical Voltage Regulator was putting out over 18 Volts have started the FD478X Ignition Coil on the way to dying?
No, it shouldn't. But it could have seen a surge that took it out like your HEI module. There is no internal voltage regulator on a coil.......like built into the HEI modules.
Quote:
That's Pertronix unit? What do THEY cost?
PerTronix Flame-Thrower HV Ignition Coils Part #60130 $77. from either Summit or Jegs. Mine is the 3 ohm unit, that is the correct part number for it, since I am still running the MOPAR Orange box and only 6 cylinders. For racing they make a 1.5 ohm coil and for high compression motors (13/1 to 15/1) a .45 ohm coil.

It is over kill at 60,000 volts but the plugs run nice especially on an old 260,000 plus mile motor....and it cools well and no more ballast resistor.
Author:  Charrlie_S [ Wed Mar 20, 2013 6:00 pm ]
Post subject: 
Stop!!!!!!!!! do not worry about whether the coil is bad or not. Coil good or bad does not make any difference, at his point. The module is not sending a trigger to the coil. Do one step at a time. Get a trigger, first. The lite dimming slightly whhile cranking is normal, do to the changing load the starter puts on the electrical system. Even if the distributer pick up is within Ohms spec, it can still have a problem. Two things to do. Remove the distribnuter, connect a low volt meter to the pickup leads, and spin the distributer. See if you get a reading. Also check the gap between the teeth on the reluctor, and the metal pole piece of the pickup coil. It should be .008 with a brass feeler gauge. If the gap is too wide it will not generate a signal. Either before or after checking the distributer, take the module to the part store and have it checked.
PS: the HEI module should still work, even if the voltage supplied by the battery is as low as about 8 or 9 volts.
Once you get trigger to the coil, then worry about whether the coil is good or bad.

PPS: Make sure the module has a good ground. Not a (-) terminal connection, but a good ground to the back, and screw hole of the module.
Author:  Aggressive Ted [ Wed Mar 20, 2013 6:04 pm ]
Post subject: 
Hopefully you have that HEI grounded good......
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