Burning up coils

[Cudaragtop]

It's a new alternator also as well as a all new M&H wiring harness.

Thanks
Mike

Got the receipt? Take it back for an exchange. Have them test the replacement if they can.

[Husker Cuda]

That is the plan for today!  They should warranty it and give me a new one.  Too bad they won't write me a check for all the headaches and coils this one cost me!

[Husker Cuda]

Took the alternator to O'reilly's and they checked and it passed at 14.6V.  So now I'm lost.  Maybe try another voltage regulator and re-check all the wiring but I have all new dash, front light and engine harnesses.  Any other ideas?

[Strawdawg]

The regulator controls the voltage.  High resistance in the bulk head connector, or elsewhere can confuse the regulator making it sense less voltage than the alternator is actually putting out.  Then the regulator orders it to put out even more.

I would start looking for voltage drops across the circuits. Maybe start checking between the output stud on the alternator and the plus pole on the battery.  Do the same between the regulator cover and the negative post of the battery.

Of you have more than a couple tenths of a volt, you have a problem

[Husker Cuda]

Thanks Strawdawg, I will check it out after work.  This work stuff sure gets in the way of working on my hot rod's!  But I guess I need to work so I can pay for all of these parts!

thanks

[HP_Cuda]

You have to ensure the Voltage regulator is grounded really well to the firewall otherwise you will have voltages all over the place and on the high side.

I had this problem for a short while and the internal wiring was getting pretty hot.

B

[Husker Cuda]

You have to ensure the Voltage regulator is grounded really well to the firewall otherwise you will have voltages all over the place and on the high side.

I had this problem for a short while and the internal wiring was getting pretty hot.

B

I did check that last night, sanded areas between the bracket and the regulator and even ran a wire from the bracket to the engine ground strap.  Nice Sublime Cuda by the way!

[HP_Cuda]

What is your average voltages while idle and when driving lately?

[dodj]

The regulator controls the voltage.  High resistance in the bulk head connector, or elsewhere can confuse the regulator making it sense less voltage than the alternator is actually putting out.  Then the regulator orders it to put out even more.

I would start looking for voltage drops across the circuits. Maybe start checking between the output stud on the alternator and the plus pole on the battery.  Do the same between the regulator cover and the negative post of the battery.

Of you have more than a couple tenths of a volt, you have a problem

There are multiple connections that can drop voltage causing the VR to be fooled into having the alt go into an overvotage state. Bulkhead connector, valve cover connector, battery connections, fusible link.....

[tman]

I pulled the regulator and made sure I had a good ground. Replaced the regulator and checked the resistor. I had right at 1.2 ohms. I checked the voltage at the positive coil and I had around 10.5V with just the key turned to the run position. I fired it up and it was running all the way up to 15.5V at 2,500- 3,000 RPM's.    I checked the alternator Batt terminal and was seeing over 17V. Oh ya I also put a new MSD blaster 2 coil on it.  So can I assume I have alternator problems?  It's a new alternator also as well as a all new M&H wiring harness.

Thanks
Mike

You mention you have new engine harness.  If your voltages are still too high, wonder if the wiring got mixed up somewhere causing the regulator being bypassed and not regulating the alternator.  Wiring manufacturing error?

[Husker Cuda]

What is your average voltages while idle and when driving lately?

The voltage drops down under 12v when idling and over 16 when it revs up. The dome light dims way down on idle and super bright when you rev up around 3000.  Put a ground wire from the alternator to the VR bracket but it didn't help any.  I ohmed all 3 VR's but the all read around 448 ohms from terminal to terminal so I don't know if that means they are all bad or all good.

[Husker Cuda]

You mention you have new engine harness.  If your voltages are still too high, wonder if the wiring got mixed up somewhere causing the regulator being bypassed and not regulating the alternator.  Wiring manufacturing error?

That is probably my next move. I may try another new regulator as I have heard they are not always good.

[Husker Cuda]

There are multiple connections that can drop voltage causing the VR to be fooled into having the alt go into an overvotage state. Bulkhead connector, valve cover connector, battery connections, fusible link.....

I think I have checked all of these and everything seems good

[Husker Cuda]

I checked the voltage drop from the + battery terminal to the battery terminal  on the alternator and it was only .2 v at idle but when I rev the motor it went up between 1.4 and 1.8v. Should the voltage drop increase with increased RPM's?  I rechecked all of the grounds ground off paint so I'm sure my grounds are good. Any other ideas?  Thanks guys!

[Bullitt-]

Check the voltage at the voltage regulator relative to the battery.  Low signal there would cause the regulator to "call" for more output from the alternator,