Alternator: clutched or not?

[TripleTransAm]

My 1st MM was assembled in mid Feb 2003. I dug out this photo of the front of the motor when I'd had it about a month, tops.

http://www.tripletransam.com/mm/early2003/DSCF7147.JPG

Is this the clutched alternator that early 2003 cars got? I understand the PCM calibrations from factory (all four?) never took advantage of this function?

My 2nd MM's alternator looks 100% the same. BUT... when I got my alternator replaced last month on the 1st MM, the alternator that was put on there appears to look the same except for that black 'disk' up front (the one with the white dab of paint pointing down to the crankshaft hub). There is no such disk on the replacement alternator... I can see the big nut holding on the pulley.

Question: did they replace my clutched alternator with a non-clutched unit or is that black disk simply a plastic cover?

[grampaws]

Plastic cover!! You can pop it off and see the bearin assembly
behind it..

[bugsys03]

My 03A had the clutch alternator. When I had it replaced under warranty about June 04 they put on a standard alternator. If you have the clutch alternator, watch your amp gauge under WOT, it will go down.

[SergntMac]

Question: did they replace my clutched alternator with a non-clutched unit or is that black disk simply a plastic cover?
Answer: Yes, somewhere in time, the clutched altenator was removed from the production line. I can't say if it was part of the 300B decontenting, or, at the start of '04 production, but it left us. Replacement altenators do not have the clutch units. And, yes, it's a plastic cap covering the bearing nut.

Anyone with a clutched altenator and SCT tuning, can have the clutch function turned off, and the altenator will produce power under WOT. Anyone with a Trilogy kit, got a non-clutched replacement pulley with the kit.

Some will say that removing the clutch function (either method) will result in belt noise (or worse hazzards) when you get up off the throttle suddenly at high RPM. I agree with the "or worse hazzards", this is an easy way to blow an engine.

[FordNut]

Well, my understanding of the whole thing is a little different so here goes:
The '03 300A and possibly the 300B had the one-way clutch on the alternator. The black cover on the pulley in the picture is commonly in place on the ones with a clutch. The function of the alternator shutoff at WOT is totally thru the PCM and the clutch has absolutely nothing to do with it. The function of the one way clutch is to reduce belt bouncing, slipping, squealing in sudden engine deceleration by allowing the alternator to freewheel. The reason for the Trilogy kit replacing the pulley with a non-clutched one is that the alternator rotates in the reverse direction with the Trilogy kit so the one way clutch would essentially always slip. Bottom line, the clutch is not important.

[Paul T. Casey]

Does this mean that perhaps someone out there would like to have my never been used alternator u/d pulley?

[carfixer]

FordNut's description is exactly correct.

All Marauders that came from the factory had the clutched alternator pulley. No replacement alternators came with the clutched pulley. So, if you see the black cap, it is clutched. If you see a big nut, it is a replacement alternator.

[SergntMac]

Wait one damn second...

I posted this...
Answer: Yes, somewhere in time, the clutched altenator was removed from the production line. I can't say if it was part of the 300B decontenting, or, at the start of '04 production, but it left us. Replacement altenators do not have the clutch. And, yes, it's a plastic cap covering the bearing nut.

Anyone with a clutched altenator and SCT tuning, can have the clutch function turned off, and the altenator will produce power under WOT.

Anyone with a Trilogy kit, got a non-clutched replacement pulley with the kit.

Some will say that removing the clutch function (either method) will result in belt noise (or worse hazzards) when you get up off the throttle suddenly at high RPM. I agree with this "or worse hazzards", this is an easy way to blow an engine. Then Brian posts this...
Well, my understanding of the whole thing is a little different so here goes:
The '03 300A and possibly the 300B had the one-way clutch on the alternator. The black cover on the pulley in the picture is commonly in place on the ones with a clutch. The function of the alternator shutoff at WOT is totally thru the PCM and the clutch has absolutely nothing to do with it. The function of the one way clutch is to reduce belt bouncing, slipping, squealing in sudden engine deceleration by allowing the alternator to freewheel. The reason for the Trilogy kit replacing the pulley with a non-clutched one is that the alternator rotates in the reverse direction with the Trilogy kit so the one way clutch would essentially always slip. Bottom line, the clutch is not important. So, which one of us is right? Or, wrong? Are we not both explaining the same thing? So...Why this post?
FordNut's description is exactly correct. All Marauders that came from the factory had the clutched alternator pulley. No replacement alternators came with the clutched pulley. So, if you see the black cap, it is clutched. If you see a big nut, it is a replacement alternator.

Y'all tell me...If I did not post a correct answer to the question as posed, show me why?

[carfixer]

Wait one damn second...

I posted this... Then Brian posts this... So, which one of us is right? Or, wrong? Are we not both explaining the same thing? So...Why this post?

Y'all tell me...If I did not post a correct answer to the question as posed, show me why?


Answer: All MM's left the factory with the clutched pulley, not just some "A"s and "B"s. Not just '03. All of em. '03 and '04.

Answer: The only function of the clutched pulley is to reduce the possibility of belt noise on heavy accel and decel, exactly as FordNut replied.

Edit: added this little copy and paste from the Ford service manual

All Marauder 4.6L 4V applications are equipped with a one-way clutch (OWC) in the generator pulley. The OWC pulley temporarily disengages the generator rotor from the front end accessory drive (FEAD) system during high acceleration/deceleration rates on the engine, which may increase belt life and decrease belt chirp. A new OWC pulley and generator/voltage regulator must be installed as an assembly.

[DEFYANT]

My company car, an 04 CVPI, also has a clutched altenator. FYI.

Mac, can you elaborate on this comment?

Some will say that removing the clutch function (either method) will result in belt noise (or worse hazzards) when you get up off the throttle suddenly at high RPM. I agree with the "or worse hazzards", this is an easy way to blow an engine.

Thanks

[Donny Carlson]

Knowing that my Marauder had a clutched alternator, I was surprised to find that the alternator in my new SSR didn't have one. Unpleasantly surprised, because there was a loud belt chirp/squeel on the 1-2 shift under WOT, a shorter chirp at the 2-3. Chevrolet had issued a TSB, the fix was to replace the alternator with a clutched alternator. My truck is an early '05 model year build, there were a set of running changes made the month after mine left the plant. Apparently the belt chirp wasn't an issue with the 5.3, but more powerful 6.0 LS2 it was.

The visial difference between the two is a black cover on the pully of the clutched alternator, just like the Marauder.

Interestingly, according to Chevy engineers, the belt squeel (which happens only at WOT) is not a durability issue, though they certainly don't hesitate to pay the dealer to change it out for free under warranty.

[CRUZTAKER]

Wait one damn second...

.....Y'all tell me...If I did not post a correct answer to the question as posed, show me why?

You know....I was thinking the exact same thing.
You both answered near exactly the same.

Perhaps Fordnut has you on his 'ignore' list and didn't see your post that basically said the same thing only didn't start out leaving one to think that "his understanding is different in some way."


Yeah...that's the ticket.:D


Anyway...my understanding is exactly what you both said.

[FordNut]

You know....I was thinking the exact same thing.
You both answered near exactly the same.

Perhaps Fordnut has you on his 'ignore' list and didn't see your post that basically said the same thing only didn't start out leaving one to think that "his understanding is different in some way."


Yeah...that's the ticket.:D


Anyway...my understanding is exactly what you both said.
but we didn't say the same thing did we?

[CRUZTAKER]

Yes.

:P

[FordNut]

Wait one damn second...

I posted this...


Answer: Yes, somewhere in time, the clutched altenator was removed from the production line. I can't say if it was part of the 300B decontenting, or, at the start of '04 production, but it left us. Replacement altenators do not have the clutch units. And, yes, it's a plastic cap covering the bearing nut.

Anyone with a clutched altenator and SCT tuning, can have the clutch function turned off, and the altenator will produce power under WOT. Anyone with a Trilogy kit, got a non-clutched replacement pulley with the kit.

Some will say that removing the clutch function (either method) will result in belt noise (or worse hazzards) when you get up off the throttle suddenly at high RPM. I agree with the "or worse hazzards", this is an easy way to blow an engine.

Then Brian posts this...


Well, my understanding of the whole thing is a little different so here goes:
The '03 300A and possibly the 300B had the one-way clutch on the alternator. The black cover on the pulley in the picture is commonly in place on the ones with a clutch. The function of the alternator shutoff at WOT is totally thru the PCM and the clutch has absolutely nothing to do with it. The function of the one way clutch is to reduce belt bouncing, slipping, squealing in sudden engine deceleration by allowing the alternator to freewheel. The reason for the Trilogy kit replacing the pulley with a non-clutched one is that the alternator rotates in the reverse direction with the Trilogy kit so the one way clutch would essentially always slip. Bottom line, the clutch is not important.
So, which one of us is right? Or, wrong? Are we not both explaining the same thing? So...Why this post?

FordNut's description is exactly correct.

All Marauders that came from the factory had the clutched alternator pulley. No replacement alternators came with the clutched pulley. So, if you see the black cap, it is clutched. If you see a big nut, it is a replacement alternator.

Y'all tell me...If I did not post a correct answer to the question as posed, show me why?

Alrighty, here is where we are agreeing and disagreeing:

We all agree that the clutched alternator was deleted at some point, whether it was during production or on replacement units is irrelevant because the clutch is not important. If there is a black cover on the pulley, it has the one-way clutch.

Mac, we disagree about how the alternator is turned off with programming. The alternator can be turned off at WOT with the PCM but it has nothing to do with the clutch. The PCM turns off the alternator by way of the regulator. The only purpose of the mechanical one-way clutch is to reduce belt noise by allowing the alternator to freewheel on engine deceleration.

Mac, I disagree with your comment that "worse hazards" such as a blown engine could occur if the clutch is removed, both because of the fact it is not used at all on the Trilogy cars and because my car has not had the clutch for approximately 40 k miles. It was removed when I installed the 8-rib pulley system. After the clutch was removed, my program still turned off the alternator at WOT until I had that feature changed with the supercharger installation.

Hope this clears it up a bit.

[Joe Walsh]

Alrighty, here is where we are agreeing and disagreeing:

We all agree that the clutched alternator was deleted at some point, whether it was during production or on replacement units is irrelevant because the clutch is not important. If there is a black cover on the pulley, it has the one-way clutch.

Mac, we disagree about how the alternator is turned off with programming. The alternator can be turned off at WOT with the PCM but it has nothing to do with the clutch. The PCM turns off the alternator by way of the regulator. The only purpose of the mechanical one-way clutch is to reduce belt noise by allowing the alternator to freewheel on engine deceleration.

Mac, I disagree with your comment that "worse hazards" such as a blown engine could occur if the clutch is removed, both because of the fact it is not used at all on the Trilogy cars and because my car has not had the clutch for approximately 40 k miles. It was removed when I installed the 8-rib pulley system. After the clutch was removed, my program still turned off the alternator at WOT until I had that feature changed with the supercharger installation.

Hope this clears it up a bit.

FORDNUT IS EXACTLY RIGHT.....I don't know why this misconception of the one way clutch's function continues to persist. We've talked about this in at least a half dozen threads.
The clutch's ONLY purpose is to allow the alternator to 'freewheel' during high rpm upshifts and thus eliminate belt chirping and squealing.
It is kinda like a bicycle's rear hub which can drive the rear tire when pedaled one direction, but cannot drive the rear tire when pedaled the opposite direction.
The clutch CANNOT be 'turned on and off' at WOT. It IS NOT an electromechanical clutch (like your AC compressor has).
The alternator's charging function CAN be shut off, by the PCM, at WOT.

BTW: As has already been stated in previous posts, the Trilogy S/C kit eliminates the clutched alternator because the S/C kit mounts the alternator 'backwards'.
Using a clutched alternator backwards will get you dead battery in a hurry.

[TripleTransAm]

By the way, the factory wiring diagrams support the fact that the alternator clutch is not electro-mechanically controlled by the PCM, in fact it is the alternator's charging function that is controlled by the PCM. No other wiring to the alternator as indicated in the diagrams.

So I'm okay with sticking with the mechanically clutched unit, then?

[David Morton]

BTW: As has already been stated in previous posts, the Trilogy S/C kit eliminates the clutched alternator because the S/C kit mounts the alternator 'backwards'.
Using a clutched alternator backwards will get you dead battery in a hurry.True, but it seems a bit of misunderstanding could be taken from your statement. To be clearer...

An alternator doesn't care which way you spin it. Clockwise or counter-clockwise the diodes are still gonna flip the voltage swings to the correct polarity and charge the battery. The reason the clutched pulley has to be removed on the Trilogy setup is because if you don't, the belt won't turn the alternator at all. All Trilogy alternators are spinning in the opposite direction from the factory, and they charge just fine.

[Blackened300a]

OK to Sum it up

Clutch on Alternator = Does nothing to shut the alternator off under WOT, Just prevents belt chirp

PCM = Shuts alternator off under WOT

Gotcha!

Jeeze you guys didnt have to type out such long paragraphs, It could have been summed up in 2 sentences!
:lol:

[Tallboy]

Let's not be so quick to jump on Mac about what he meant by "worse hazzards". He never said a word about the clutch mechanism damaging anything. Re-read his post. He said "when you get up off the throttle suddenly at high RPM", and on this fact he is exactly correct. Abruptly lifting at very high RPM can be quite fatal, indeed. That's why I gently roll out of the throttle at the end of my 1/4 mile runs.

Many, if not most engines, blow up on decel, not accel. I was told this by a friend who builds Nascar and Porsche race engines, FWIW.

[JMan]

Let's not be so quick to jump on Mac about what he meant by "worse hazzards". He never said a word about the clutch mechanism damaging anything. Re-read his post. He said "when you get up off the throttle suddenly at high RPM", and on this fact he is exactly correct. Abruptly lifting at very high RPM can be quite fatal, indeed. That's why I gently roll out of the throttle at the end of my 1/4 mile runs.

Many, if not most engines, blow up on decel, not accel. I was told this by a friend who builds Nascar and Porsche race engines, FWIW.

That is quite true. When accelerating or even maintaining speed, the force is linear: that is in line with the connecting rods. When decelerating, there is no longer any linear force on to the piston/rod assemblies. At that point the force becomes mostly centifugal (Outward) and no longer is in the direction of normal movement or crankshaft rotation. This is also true of valve train and transmission assemblies as well to some extent.

A bad analog would be driving down an off-ramp. If you maintain or increase the speed in the direction your front wheels are turned, the car doesn't lean as much. If you let off during the decent, the car tends to "push" outboard. That's directional force versus centrifugal force. Of course there's a limit and balance to everything [Insert disclaimer here!]. Like I stated, a bad analog yet one you have experienced first hand.

J

[SergntMac]

Anyone with a clutched altenator and SCT tuning, can have the clutch function turned off, and the altenator will produce power under WOT. Anyone with a Trilogy kit, got a non-clutched replacement pulley with the kit. Most of this confusion is my fault, this paragraph is very poorly worded, and it's thrown folks off in their replys. Everything I said is true, but I said it all wrong. My apologies to all.

There is no relationship between the clutch action of the altenator pulley and EEC programming. My bad. Moreover, there once was a clutch, now there isn't, and I know very little more about all that. Not knowing more, I should not have made the comment. My bad again. BTW, I still have my OEM clutched altenator.

It's also true you can turn your altenator on full time via EEC software, and I strongly recommend this to anyone who races, or, drives hard on a routine basis. With the altenator shut off under WOT, the whole car and all of it's devices and accessories are driven by the battery. A "brown out" is possible, and the device furthest away from the battery will suffer first. That device is the electric fuel pump, and when voltage drops, pump speed drops and fuel flow to the front of the car is affected. The end result is a lean condition at high RPM, and just when you're begging for more power to win the race, you run out of fuel. This is the rationale for adding a Kenne Bell Boost-a-Pump, which boosts the voltage to the fuel pump under WOT. However, with out a BAP in place, one is asking for trouble. BTW, don't race with less than 1/4 tank of fuel, baffles inside the fuel tank can cause the pumps to run dry during WOT.

Now, there is a device in the trunk called a "fuel pressure delivery module" that monitors the fuel system. When it senses a disruption in expected behavior, it reacts, and that reaction is to shut down the fuel system. This, of course, is potentially harmful to the engine. Sudden loss of fuel and spark at high RPM will twist a con rod and window the block, usually #4 or #8, but all are at risk. This is the same as jumping off the throttle at high RPM. Bad, very hard on stock con rods, forged rods are not immune, but that's another thread.

So, you see how I fu*ked this up, don't you? Right train, wrong set of track, or, something like that? Ya know, I never should have brought it up in the first place.

Oh...One other thing. I've got a Helms book, actually two, dated 7/2002, just a few weeks after my MM came off the production line. This is what the techs at my dealership use, that why I bought it. Anyway, I peeked at it briefly this morning before leaving for work, wanting to see how close FordNut was to the actual text of the book, i.e. exactly.

If I am to trust in, and believe everything I read in this tech manual, we all have a problem, folks. According to Helm, as of 7/2002, Marauders do not have an altenator. That's right, no altenator, nope.

We have generators, and regulators, and the sketches look just like what's under my hood, but no altenators. The word's not even listed in the index. So much for exactly out of the book, eh?

In the words of John Bon Jovi...have a nice day...

[metroplex]

Can the clutch be retrofitted to Crown Vics?

I have a 4G alternator that is used on the Mark VIII / Cobra (6G is used on CVPIs and Stangs) which looks just like the MM alternator.