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As the '55 Model Year Coordinator I received a letter (that's right, a letter!) from a member in Delaware with a '55 Firedome he has owned since 1971! He has been failing voltage regulators and asked for assistance. My automotive repair skills are minimal, especially electrics. I know that many of you have the skill and knowledge and will have some recommendations. Here is a summary of the letter:
"With the most recent replacement voltage regulator I installed having just failed, this is the third regulator that has been installed in the last thirty months. While I recognize that the replacement regulators aren't built with the same quality of materials as the original units, nonetheless I am wanting to insure that there might not be an issue that has been overlooked that is contributing to the failure rate I have experienced.
By way of background, I have previously confirmed that the generator output is within tolerance, the drive belt has the correct tension and that the voltage regulators that have been installed were properly grounded.
In researching a replacement part, I noted that the voltage regulator offered by NAPA carries a recommendation for the concurrent replacement of the voltage regulator fuse. Could you give me some insight as to the role of this particular fuse? Having never replaced the voltage regulator fuse, is it a component that could be working only intermittently or like most fuses is it a component that is either functioning or not?
Is there any other diagnostic action that you would recommend I undertake before installing a replacement part?
I believe that I have located an NOS voltage regulator. Alternatively, if this part is not available is there any brand of new replacement regulator currently sold that from your experience offers reliable service?"
Personally, I've had to replace only one regulator on my '55 Firedome in thirty years, so I've not had this sort of problem and can't speak from experience.
I'll gather your responses and send a reply to this inquiring member. Thanks in advance for your assistance!
Mark K.
Do you know if he has polorized the generator/regulator?...
Do you know if he has polorized the generator/regulator?...
Tony...no I do not. I copied his letter word-for-word so that is all we know.
Mark
Tony is correct about the polarizing of the generator/voltage regulator. I do not recall the procedure but it is in the shop manuals. Both the generator and voltage regulator may need to be polarized. I have not had to do this lately. One of the primary reasons for alternator failure seems to be connecting jumper cables. For some reason, it seems to have caused my 53 problems over the years but not for a long time now that I never connect any.
If I recall correctly, voltage regulators are sold either positive/negative ground; possibly buying a negative ground regulator for a positive ground car? Also, 12v instead of 6 volt?
It's hard to tell from just his letter if he's dealing with a competent parts counter person.
It doesn't sound as though polarizing would be the issue as he indicates that the output of the generator is within limits.....
It's supposed to be fun!
1949 De Soto Custom Convertible (project)
Responding so this string gets to the top of the list. Anyone have any more ideas regarding this problem?
Mark
Looky here. The Imperial club guys really got it going on. They know their stuff and aren't afraid to share it.
http://www.imperialclub.com/Repair/Elec ... erator.htm
Have a nice day
Steve
Steve...great link! Lots of good information. Thanks!
Mark
I am withe Tim's answer especially on the 12 v vs 6 volt and the positive ground. The kids at NAPA may not have any idea of this. The 55 is the last year for the 6 volt system, isn't it?
