ConcoursMustang Forums

1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1964 1/2 - 1965 => Topic started by: CharlesTurner on November 28, 2018, 11:35:55 AM

Title: 38A or 42A Alternator
Post by: CharlesTurner on November 28, 2018, 11:35:55 AM
Starting a new topic as the post regarding correct battery is getting more into a discussion about alternators.

For 65-66, the assembly manuals list either a 38A or 42A alternator, with the 42A being an RPO.  The 65 assy manual shows the RPO as Z-102, but the 66 one shows Z-120.  Not sure if that is a typo, or if the RPO is just for the alternator or part of a different option.

The discussion for this topic is surrounding how a specific car would have been equipped with the optional 42A alternator.  Based on some original examples, A/C, power top, nor the HD battery option appear to have 'triggered' an automatic alternator upgrade. 

Build sheets have a place for the alternator, blank would be a 38A and I believe '8' would be for a 42A.  Would be great if anyone has build sheets with the 8 for 42A alternator to share.  Maybe we can determine a pattern?

Also, related to the discussion, the 65-66 assembly manuals do not call out a different voltage regulator for either the 38A or 42A alternator.  This would mean all 65-66 should have the silver ink-stamped regulators, C5AF-10316-A.
Title: Re: 38A or 42A Alternator
Post by: krelboyne on November 28, 2018, 12:28:34 PM
Maybe fog lights?
Title: Re: 38A or 42A Alternator
Post by: jwc66k on November 28, 2018, 04:08:09 PM
Maybe fog lights?
That would include 65-66 Mustangs with the the GT option, and none of the several GT's I've owned have it listed. See the window sticker.
Jim
Title: Re: 38A or 42A Alternator
Post by: jwc66k on November 28, 2018, 04:26:38 PM
The 65 assy manual shows the RPO as Z-102, but the 66 one shows Z-120. 
The 65 Mustang Electrical Assembly Manual, AM0008 pg 11 shows the option reference for the battery as O-106 for a C5AF-10655-B 55A battery.
The 66 Mustang Electrical Assembly Manual, AM0013 pg 17 shows the option reference for the battery as Z-106 for a C5AF-10655-B 55A battery.
Consistently inconsistent.
Jim
Title: Re: 38A or 42A Alternator
Post by: Bob Gaines on November 28, 2018, 07:16:35 PM
Starting a new topic as the post regarding correct battery is getting more into a discussion about alternators.

For 65-66, the assembly manuals list either a 38A or 42A alternator, with the 42A being an RPO.  The 65 assy manual shows the RPO as Z-102, but the 66 one shows Z-120.  Not sure if that is a typo, or if the RPO is just for the alternator or part of a different option.

The discussion for this topic is surrounding how a specific car would have been equipped with the optional 42A alternator.  Based on some original examples, A/C, power top, nor the HD battery option appear to have 'triggered' an automatic alternator upgrade. 

Build sheets have a place for the alternator, blank would be a 38A and I believe '8' would be for a 42A.  Would be great if anyone has build sheets with the 8 for 42A alternator to share.  Maybe we can determine a pattern?

Also, related to the discussion, the 65-66 assembly manuals do not call out a different voltage regulator for either the 38A or 42A alternator.  This would mean all 65-66 should have the silver ink-stamped regulators, C5AF-10316-A.
Charles , the C5AF (C8AF for 68-70) marked silver stamped regulator was used on the 38 or 42 amp alternator from 65-70 Mustang according to the various year specification manuals. The C5TF yellow stamp regulator (C8TF for 68-70) was paired with the 55 amp alternator.
Title: Re: 38A or 42A Alternator
Post by: CharlesTurner on November 28, 2018, 09:00:43 PM
Charles , the C5AF (C8AF for 68-70) marked silver stamped regulator was used on the 38 or 42 amp alternator from 65-70 Mustang according to the various year specification manuals. The C5TF yellow stamp regulator (C8TF for 68-70) was paired with the 55 amp alternator.

I was pointing that out as I recall somewhere it was stated (not here) that power top or A/C cars should have the yellow stamp regulator for 65/66, which does not appear to be correct... and as you point out was paired with a 55A, which wasn't available on 65-66 cars.
Title: Re: 38A or 42A Alternator
Post by: sgl66 on November 28, 2018, 09:26:38 PM
 

Build sheets have a place for the alternator, blank would be a 38A and I believe '8' would be for a 42A.  Would be great if anyone has build sheets with the 8 for 42A alternator to share.  Maybe we can determine a pattern?

My build sheets have the “8” for alternator which according to the buildsheet thread is for 42A and standard for HiPo cars http://www.concoursmustang.com/forum/index.php?topic=3925.30

I also have a “2” in the battery section on the build sheet and the HD battery on the dealer invoice.

If it’s true that HiPo cars by default came with 42A alternators, did they also come with HD batteries? I’m trying to think of why you would have one without the other on a HiPo car or any car?

Title: Re: 38A or 42A Alternator
Post by: CharlesTurner on November 28, 2018, 10:13:52 PM
More info:

Build sheets:
66 A code GT, 38A, HDB (heavy duty battery)
66 A code GT, 38A, HDB
66 K code GT, 42A, HDB (code 2)
66 K code, non-GT, 42A, HDB
66 A code GT, illegible, HDB (code 2)

Window stickers:
64.5 K code, no HDB

65 K code, non-GT, (5) without HDB, (1) with HDB

66 K code, GT (2) with HDB
66 K code, non-GT, no HDB


This doesn't really help with much other than maybe starting in 66, the 42A became a requirement for K codes.
Title: Re: 38A or 42A Alternator
Post by: J_Speegle on November 28, 2018, 10:34:25 PM
Will try and find a little time to go through the buildsheets and window stickers I have to share and help out a little
Title: Re: 38A or 42A Alternator
Post by: sgl66 on November 28, 2018, 10:38:47 PM
Thanks, I still think cars delivered to colder climates may factor in to the HDB equation and worth keeping an eye on.

Also wonder if the higher compression and heavier springs on the HiPo made them shift to the HDB in 66 if issues popped up in 65? guessing of course
Title: Re: 38A or 42A Alternator
Post by: J_Speegle on November 28, 2018, 10:43:15 PM
Thanks, I still think cars delivered to colder climates may factor in to the HDB equation and worth keeping an eye on.

Won't close my eye to the watch for something. That is how we learn/discover new things or reinforce current belief's :)
Title: Re: 38A or 42A Alternator
Post by: PerkinsRestoration on November 28, 2018, 11:17:45 PM
Both 69 & 70 Boss 429 use 55 AMP alternator and use C8AF 10316-A regulator. All nos Autolite service regulators were TF type with yellow print. I believe it was very common  C5AF-10316-A and C8AF-10316-A regulators were replaced by the service TF regulators at some point.
Title: Re: 38A or 42A Alternator
Post by: Bob Gaines on November 29, 2018, 01:07:33 AM
Both 69 & 70 Boss 429 use 55 AMP alternator and use C8AF 10316-A regulator. All nos Autolite service regulators were TF type with yellow print. I believe it was very common  C5AF-10316-A and C8AF-10316-A regulators were replaced by the service TF regulators at some point.
Bob ,I don't dispute what you have seen . I have heard your opinion on this subject before. I just assume it is a anomaly limited to a few applications like the Boss 429 . Yes every NOS service regulator I have ever seen had a C5/C8TF yellow stamped regulator inside the pull string to open box. I figured service options in this regard differed from assemblyline because of Ford cost savings because of lower inventory different numbers.     Just reporting what the 65-70 service specifications books read.  I posted a picture from page 14-2 of the 69 book for example that reads 38,42 amp alt had the silver C5/C8AF and 55 amp alt had the yellow stamp C5/C8TF. The other year books read the same. Don't shoot the messenger.
Title: Re: 38A or 42A Alternator
Post by: PerkinsRestoration on November 29, 2018, 11:06:54 AM
Bob, I think your info  apply's prior to 1969 model year as Boss 302's, Boss 351's and most 428 CJ's  typically had AF regulators. I have never seen a yellow TF on a Boss 302,351,429 or 69/70 428CJ. Even the unrestored 70 Mach 1 with AC has a Silver AF. It also has the original battery born with in the car.  I don't believe the C8AF and later regulators were adjustable either? The old Bob Graff 6,000 mile white GT 500 has a silver C8AF regulator . No doubt an original AF regulator with original paint is much more rare find than a TF. Most but not all my observations are DAP cars except 1970 Boss 302.
Title: Re: 38A or 42A Alternator
Post by: krelboyne on November 29, 2018, 12:11:04 PM

If it’s true that HiPo cars by default came with 42A alternators, did they also come with HD batteries? I’m trying to think of why you would have one without the other on a HiPo car or any car?

Comment on the HiPo alternators. They had larger diameter pulleys, I reckon that may have something to do with them being a higher output?
I don't understand electronics, but worth mentioning.
Title: Re: 38A or 42A Alternator
Post by: jwc66k on November 29, 2018, 12:49:09 PM
Comment on the HiPo alternators. They had larger diameter pulleys, I reckon that may have something to do with them being a higher output?
I don't understand electronics, but worth mentioning.
The larger diameter pulley on the standard alternator used on 63 thru 67 Ford cars with the 289 High Performance engines was to lower the RPM at the alternator because the 289 HP engines were capable of sustained revolutions well over 6,000 RPM. It was a method to increase alternator bearing life too.
Jim
Title: Re: 38A or 42A Alternator
Post by: J_Speegle on November 29, 2018, 07:03:21 PM
Went through my copies of buildsheets for 65 and offer the following you'll notice that I included the DSO and extension (if printed) to respond to sglbbs' focus on those ;)

Hopefully the following is usable in the study and discussion

Plant -Eng-Alt-----Battery---DSO----Ext-   BS Date
5R-----A---Blank --Blank-----?-------Blank   16M
5T-----C---Blank   --Blank-----95 -----Blank   07R
5T-----K---Blank   --Blank-----13 -----Blank   12R
5T-----C---Blank   --Blank-----95 -----Blank   21R
5T-----C---Blank   --D----------26 -----Blank   07S
5T-----K---Blank  ---A--------- 11 -----Blank   13S
5T-----C---Blank  ---D---------15 -----Blank   18S
5T-----C---Blank   --D--------- 12 -----Blank   21S
5T-----C---Blank   --Blank -----95 -----Blank   08U
5T-----C---Blank   --Blank -----24 -----Blank   26U
5T-----C---Blank   --Blank -----24 -----Blank   26U
5T-----T---Blank   --Blank -----21 -----Blank   28U
5T-----C---Blank   --D ---------22   ---Blank    11V
5?-----C---Blank   --A ---------? ---------?         ? (Carried a 174042 VIN)

Title: Re: 38A or 42A Alternator
Post by: J_Speegle on November 29, 2018, 07:26:01 PM
And for 66 from buildsheets. Convertibles are noted this time just in case that might have made a difference which it appears not have had.

Plant -Eng---Alt-----Battery-   DSO-   Ext-   BS Date
6T-----A-----Blank-----1----------18   Blank   27J
6T-----K-----8---------1----------75   Blank   07K
6T08   K-----8---------1   ----------?   ?        22K
6T-----A-----Blank-----1----------21   Blank   25K
6T-----A-----Blank-----1----------21   Blank   25K
6T-----A-----Blank-----1----------21   Blank   25K
6T08   T-----Blank   ---1----------15   Blank   05L
6T-----K-----8----------1----------14   Blank   10L
6T-----A-----Blank-----1----------22   Blank   02M
6T-----T-----Blank-----1----------15   Blank   04M
6R-----K-----8---------1----------71   2611   18M   
6T-----A-----Blank-----1----------11   1514   29A
6T-----C-----Blank-----1----------22   Blank   02B
6T-----C-----Blank-----1----------37   Blank   03B
6T-----A-----Blank-----1----------21   Blank   01D
6T08   C-----Blank-----1--------- 24   Blank   04D
6T-----C-----Blank-----1----------21   Blank   15D
6F-----K-----8----------2----------35   Blank   26D
6T08   T-----Blank   ---1----------13   Blank   10E
6T-----C-----Blank-----1----------17   Blank   13E
Title: Re: 38A or 42A Alternator
Post by: T_Kaminski on April 06, 2019, 12:40:12 PM
The larger diameter pulley on the standard alternator used on 63 thru 67 Ford cars with the 289 High Performance engines was to lower the RPM at the alternator because the 289 HP engines were capable of sustained revolutions well over 6,000 RPM. It was a method to increase alternator bearing life too.
Jim

From a technical standpoint, use of the 42A alternator in Hi-Po applications would make sense.  The 38A may have proved inadequate to charge the battery at idle or normal driving, due to the lower RPM ratio.