On Tuesday of last week, this 1965 Buick Skylark was driven through the semi-rural areas surrounding an average mid-sized, midwestern city. The owner enjoyed himself, wife by his side, the Buick’s engine burbling contentedly. On Wednesday, however, the same man turned the key of said Skylark, finding nothing but silence where heretofore was noise, darkness where there once was light. Had the Skylark been abducted by aliens? Substituted for another Buick? Or was there something more sinister going on? Find out next on Curbside Case Study.
This program is about unsolved mysteries. Whenever possible, the actual family members and police officials have participated in recreating the events. What you are about to see is not a news broadcast. ***Insert ominous music here***
Wait…wrong program. With that being said, if you have no business under the hood of an automobile nor any concept of electrical diagnosis, don’t try this at home. Neither the author nor this website takes any responsibility for your ineptitude. The following is a reenactment of actual events.
As previously mentioned, turning the Skylark’s ignition key produced no expected outcomes, no cranking, no clicking, no charging system dashboard light, no manifestation of life in any of its forms. After a moment of confusion, much hand wringing, and gentle mourning, the Skylark’s owner got down to the business of diagnosing his no-start condition. First, he checked the interior lighting to rule out a problem with the ignition switch: It was as dim as the last rays of a prairie sunset. He knew the battery was dead, stone dead.
The battery was only five years old. The Skylark’s owner was puzzled by the early demise of his parts store battery, but his years as a mechanical investigator made him suspicious. Upon hooking up his digital multimeter and selecting DC voltage on its dial, he found a mere five volts remaining in what was, until recently, a battery in the prime of life. Was this death by natural causes, or was it murder?
After hooking up the 10 amp charger to the battery for a quick 20-minute resuscitation, the owner performed a simple parasitic draw test using a test light. By disconnecting the negative terminal of the battery, and connecting the test light between the two, he found that the light glowed brightly. There was a parasite in the system, a parasitic draw to be exact, and that test light was a snitch. Several feet away, a guilty party grew very nervous.
The owner thought back to the previous autumn, when an old mechanical voltage regulator had attempted to murder, by overcharging, the exact same battery that was now in such grave danger. When the owner replaced it with a solid-state regulator he kept as a spare in the garage, little could he have known that the two parts were complicit. How could they have been caught? They never even came in contact with one another; it was the perfect crime, but the accomplice got greedy. He tried to kill the battery in one night, through an internal short.
The mechanical regulator was last heard cursing its one-time friend as the owner set them side by side for the final test. The connector was swapped between the two, and the test light told its tale: no light, no short. The solid state regulator was guilty. In court, the mechanical regulator was heard shouting, “Nobody would have known! I was killing him slowly! They would have thought it was natural causes!” The solid state regulator was executed by garbage bag, while the mechanical regulator, guilty of attempted murder, was placed in lifetime solitary confinement as an emergency spare.
But the battery was not yet out of danger. The replacement Duralast regulator that the owner purchased at the local parts store was far from innocent. Upon installing it, the owner discovered that the car’s electrical connector did not securely attach to the new regulator, and the alternator was now only charging at 13 volts at idle, 14 volts as the engine sped up. The owner searched for a steady 13.8-14.5 volts at all speeds. How did he know the alternator wasn’t bad? As a final humiliating punishment before their fates were sealed, he used the guilty regulators to test charging voltage. The alternator was found not guilty.
Desperate, the owner/investigator visited the website of Summit Racing in Ohio and ordered a “Tuff Stuff” solid state regulator for a mere $18 plus shipping. Despite the “creative” spelling of the regulator’s manufacturer, the owner looked forward to better days with his beloved Skylark, prodded gently by good reviews on the Summit website.
After the installation of the “Tuff Stuff” regulator, the owner observed a charging voltage of 14.54 volts: a little high, but the battery was slightly undercharged by the attempt on its life. The owner bravely took the car on another long, rural jaunt.
Upon his return, the owner used his Power Probe III to verify that the regulator was operating as it should. It was.
The dial showed 14.1 volts at all speeds with a warm engine. There was no parasitic draw. This mystery is solved, for now.
As Robert Stack might have said on Unsolved Mysteries, “For every mystery, there is someone, somewhere, who knows the truth. Perhaps that someone is watching. Perhaps… it’s you.”
Luckily for this Skylark, someone was watching. And he knew the truth.
Epilogue from owner, who finds it appropriate to change to first-person narration: Whenever I find a problem that I don’t often deal with, I find it helpful to pull out the shop manual for the offending automobile.
Therein, I read and reread the section that explains the function of the guilty system until I understand all possible culprits. In this case, I started with the voltage regulator because I’ve had these problems before and it was the last electrical part I had replaced. If that wouldn’t have been the problem, I would have started pulling fuses first, and working my way through every circuit until my test light went out (while I was performing the parasitic draw test).
I only referenced the shop manual afterward to brush up (pun) on my 1960s General Motors charging systems.