88 New Yorker- SLOW turn signals????!!

Dont know if this is your problem but check that all the bulbs are functioning... On my truck, when a bulb is burned out, the flashers flash slow...

functioning... On my truck, when a bulb is burned out, the flashers flash slow...

Low voltage can cause problems too.

functioning... On my truck, when a bulb is burned out, the flashers flash slow...

One other thing ... this is mainly a problem when it rains. On dry days the (left and right) indictors flash slowly (once every 4 seconds) but not as bad as rainy days ( every 8 seconds). My battery is good so I don't think it's a voltage issue. ( I'll still check it). It must be a bulb issue. ???

Sounds to me like it's definitely voltage. When it rains, you've got your wipers on, and probably the headlights too. Maybe even the defroster.

Saying your "battery is good" was totally wrong-thinking. Your battery dictates the voltage of your electrical system when the engine is OFF. The problem is your old alternator has 2/3 of the field coils dead, or a diode burnt out, and what-not, and it only puts out about 20 amps. Maybe you're at

Your alternator just barely keeps the battery charged, and you don't notice it, but the blinker notices it. It's actually a very good indicator of the operating voltage of the system with the engine running. Although I don't know why, I've found them to be pretty consistently affected by minor voltage changes. I won't bore you with the anecdotes.

Except that alternators do not have "field coils". They have rotors and stators.

The field coil is attached to the rotor. It produces a magnetic field which cuts across the coils in the stator as the rotor turns, inducing an alternating electrical current which is fed to diodes to change it to a pulsating direct current.

So are we saying I need a new alternator?

Probably. Check the voltage across the battery with the engine on, the wipers on, and the flashers on. It should read at least 12.5 volts if your charging system is working properly. You could also remove the old alternator and take it to one of the auto parts stores (AutoZone, Pep Boys, etc.) and have them test it. That's usually a free service.

doc

What is *actually* needed is proper diagnosis to figure out whether the problem is localized to the turn signal system or whether the turn signal problem is indicative of a systemwide issue. You've replaced the flasher with no improvement, but you mention no other symptoms (hard starting/slow cranking, dim headlights, etc.), so we don't yet have enough information to nail down the problem.

Put a voltmeter across the battery with the engine off, and you should see a reading in the close vicinity of 12.6 to 12.8 volts. Start the engine, confirm that the turn signals are doing their slow-flash thing, then put the voltmeter across the battery again. You should see a reading in the range of 13.2 to 14.5. If the voltage does not increase thus with the engine running, your alternator is not charging correctly and you then need to move on to diagnosis of the charging system -- the problem could be with the alternator itself, with the voltage regulation circuitry located in the engine control computer, or with the wiring between the two.

If the battery voltage is approximately 2 volts low with the engine off (range of 10.2 to 10.6) your battery has a dead cell; replace it.

If the voltages (engine-off and engine-on) are as prescribed above, your charging system is fine and you need to look elsewhere for the problem -- most likely you'll find burned out turn signal bulbs, corroded/broken signal bulb socket wires, or corroded/broken signal bulb socket grounds.

-Stern

No, the *rotor windings* are attached to the rotor.

The stator windings, oddly enough, are attached to the stator.

Starters have field coils. So do generators. Alternators do not.

-Stern

They do.

Some easy references (plenty more available):

I think this is similar to the valve lifter/lash adjuster terminology (non)debate. Note also, to further confuse the semantics, that alternators are now being referred to as "generators" by several of the auto manufacturers - Chrysler for one.

For the record, I think it would be correct to say (assuming certain understood constraints on the meanings of the words) that all (automotive) alternators are generators, but not all generators are alternators (if it is accepted that the term "generator" means that the final output is d.c., and not just any rotary device that generates electrical power, and that the term "alternator" means a rotary device that internally generates a.c. but that the a.c. is rectified to d.c. before reaching the outside world - i.e., that looked at as a black box, is a d.c. generator). This is why I say that this type of discussion is more one of semantics rather than technical correctness.

I will add that, taking words in their purest form, there is no reason that the term "generator" could not be used to mean an unrectified (or as they would say in the Navy "un-rectumfried) a.c. generating device, and similarly that the term alternator would most definitely be the appropriate term for such a device, even though in the automotive world, it is always understood to have a final output of d.c. - which would be a ridiculous constraint on the generic meaning of the word.

It's all context and semantics. The important thing for technical discussions is that those engaged make clear how they define their terminology. Even if they disagree on those constraints (and even if the terms themselves are technically incorrect - like calling a device that puts out d.c. power an alternator), they can understand each other if they know what the other means when he uses a certain term.

Ten years ago, you would likely have been told on an automotive forum that you were wrong if you called what we know as an alternator a generator, yet today, that's what the manufacturers themselves are calling them.

Things that make you go "hmmmm"...

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

By all automakers, actually, since it's now covered in the SAE standardized component and system terminology standard. This is why Chrysler, having since 1976 called a particular device an Automatic Idle Speed (AIS) motor, now calls it an Idle Air Control (IAC) motor, same as everyone else.

Disagree. Let's take this idea to its obvious and ridiculous extreme:

When honing the cylinders on a Ford 2.3 litre 4-cylinder engine, it's important to use the correct stone grit. By "honing" I mean "adjusting", by "cylinders" I mean "valves", by "Ford 2.3 litre 4-cylinder engine" I mean "Chrysler 225 cubic inch 6-cylinder engine", by "stone" I mean "wrench", and by "grit" I mean "size".

Disagree. That's what General Motors has been calling them right from the start ("Delcotron Generator").

-DS

You're right - that is a ridiculous extreme, but your point is made. I still think my point is valid on this "rotor winding"/"field winding" debate. Both sides are right - and I don't mean that in a New Age I'm-OK-you're-OK feel-good sixties-were-good-to-you group-hug kind of way. 8^)

I think doc convincingly made his point with those links, and it would be hard to give an argument on why you can't call the rotor windings field windings - unless one wants to define the term "field winding" in a way that excludes their being part of a moving armature, which I think makes my point (about defining terms). It is what creates the magnetic field and is modulated to regulate the voltage output by the alternator. The fact that it is rotating does not make it any less of a winding that generates the magnetic field.

I did not know that (said in a Johnny Carson voice). I'd always heard the term "alternator" emphasized as distinct from generator ever since the auto industry changed over (when I was a kid). I'm thinking people would have "corrected" you on the terminology (altrernator/generator) soon after that to make sure everyone understood that the d.c. generators were not being used (even though technically an alternator is a generator). I could be wrong on that too.

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

Dan - you are being anal again. The magnetic field required to cause an alternator to generate power is produced by field current, flowing through the field coil, which is located on the rotor.

You can call it anything you like - does not change the FACT that it is a field coil.

Had "Doc" claimed that alternators had "field windings", he'd be right. But he didn't. He claimed they have "field coils", which they do not. Field coils, by definition, are (Class? Anyone? Buehler?) Coils.

The rotor windings in an alternator are many things. They are metallic, they are insulated, and they are ever so cute, but they are not coils.

Open an alternator up someday and take a look.

You didn't read a single one of those links I provided, did you?

The rotating field in a typical alternator is created by a single COIL of copper wire wrapped around the shaft. Folded interlocking iron "fingers" carry the resulting magnetic flux to the correct position for it to interact with the stator coils. Its a type of "salient pole" rotating machine, except that a single coil is used to energize all of the iron pole-pieces instead of multiple coils carried on individual pole pieces.