Topic: Correct Battery

[Bob Gaines]

It may have been a 65-66 thing.  Posting numerous examples of build sheets of cars with A/C, but no HD battery.  Have examples of window stickers with A/C and also HD battery.  I also have the order punch card for a '66.  It was ordered with A/C and HD battery, but there is no call out for anything other than the base alternator/regulator.  Just going by the documentation, but it does not appear A/C, nor power top automatically triggered an HD battery (at least for 65-66).

It could be 65/66 thing and also if the HD battery was part of the option in the case of the air conditioning it might not be listed separately because it was part of the AC option. For instance we know that the cars came with 38,42,and 55 amp alternators but I don't recall that being a spelled out option on a widow sticker or Marti report in the case of 67-up. The same goes for the regulator. We know that a C5AF  silver regulator goes with a 38 or 42 amp alternator and the C5TF goes with the 55 amp alternator. I have never seen that spelled out ether . I always assumed that it was triggered with another option that required a different amp alternator. I am guessing that same thing applied to the Air Car that got a upgraded battery but it wasn't listed. I have also seen what I think is a anomaly where the hd battery is listed on a air car when normally it wouldn't . I have seen other examples of this also . Recently there was a discussion on 67 Shelby AM radios. The 67 Shelby package came with the AM radio but sometimes it was listed on marti reports that it was a option. The vast majority of the time it was not noted on the Marti but the car still got the AM radio. Not 100% for sure but my best guess given the way I interpret the evidence.  I am not trying to be contrary on purpose but it could be as far as the dealer specifically ordering a HD battery that may be the dealer was unaware of the upgraded battery that automatically came when you ordered A/C so he check what he desired to be included.

[Bob Gaines]

If the car came with the C5TF yellow stamped regulator then you know it got the 55 amp alternator and also the higher capacity battery. The alt /regulator information is unfortunately not listed on window stickers but would be on the uncommon build sheet (besides personal observation). That was why I suggested going that route to help get to the bottom of this issue. 

[ChrisV289]

Perhaps Mike can chime in since his un-restored honey gold convertible has AC, so he should have the original alternator with it.  I dont know if he has the original battery that came with it.

[CharlesTurner]

Perhaps Mike can chime in since his un-restored honey gold convertible has AC, so he should have the original alternator with it.  I dont know if he has the original battery that came with it.

His car has an alternator with a 50 marking on it.  The window sticker calls out A/C and then also HD battery.  Don't think he has the order info.

[sgl66]

It may have been a 65-66 thing.  Posting numerous examples of build sheets of cars with A/C, but no HD battery.  Have examples of window stickers with A/C and also HD battery.  I also have the order punch card for a '66.  It was ordered with A/C and HD battery, but there is no call out for anything other than the base alternator/regulator.  Just going by the documentation, but it does not appear A/C, nor power top automatically triggered an HD battery (at least for 65-66).

Most of these documents other than 1 in Iowa are in warmer areas of the country. Just a guess but perhaps many cars shipped to parts of the country with freezing temps in the winter were ordered with HD batteries for more cold cranking amps.

Also just checked my buildsheet again for alternator which was an “8” 42 amp with the HD battery

http://www.concoursmustang.com/forum/index.php?topic=3925.30

[CharlesTurner]

The 65-66 assembly manuals (which we know are not necessarily the gospel), only show 2 alternators, 38A (std) and 42A optional.  It also notes that the same regulator is used for both, with marking C5AF-10316-A.  The 2 battery options are also noted.

The 65 assy manual notes that the 42A alt is RPO Z-102 (or part of)... although 66 has it as a Z-120, so not sure if one is a typo?

[J_Speegle]

Most of these documents other than 1 in Iowa are in warmer areas of the country. Just a guess but perhaps many cars shipped to parts of the country with freezing temps in the winter were ordered with HD batteries for more cold cranking amps.

Dealers, knowing where the car was to be delivered could have talked the owners into upgrading to a bigger alternator/system, marked the box and charged more. That would have been noted (in the boxes for alternator and battery). Haven't seen anything that would back up that though. It would take allot of marti reports to cross check and see if there was a higher percentage of this and it might be different from dealer to dealer

[Bob Gaines]

His car has an alternator with a 50 marking on it.  The window sticker calls out A/C and then also HD battery.  Don't think he has the order info.

38 amp is purple stamp.

[Bob Gaines]

I just pulled out my trusty 1966 service specifications and it shows that the 55 amp alternator (red stamp) was not available on Mustang. There are sure a lot of wrong installations out there. I think that is one of the more common color of stamps I see on 65 and 66 's on the show field.

[petersixtfive]

Found this some time ago when researching alternator stamp colours

[mgmradio]

Both of my unrestored June 65 cars have purple stamped alternators and have heavy duty battery on the window stickers. I have the order sheet for the convertible and it also lists the heavy duty battery.
  My Aug 64 car has a purple stamped alternator. I don't have the window sticker for it ,but do have the order sheet. It lists heavy duty battery.

[CharlesTurner]

Both of my unrestored June 65 cars have purple stamped alternators and have heavy duty battery on the window stickers. I have the order sheet for the convertible and it also lists the heavy duty battery.
  My Aug 64 car has a purple stamped alternator. I don't have the window sticker for it ,but do have the order sheet. It lists heavy duty battery.

If they're all purple, then that would normally indicate a 38A alternator... which contradicts an automatic triggering of either A/C or the HD battery requiring a higher output alternator.

[CharlesTurner]

I think that is one of the more common color of stamps I see on 65 and 66 's on the show field.

The orange 42A stamp is the most common I've seen on restored cars.

[ChrisV289]

Does power steering also factory into this as well?

[CharlesTurner]

Does power steering also factory into this as well?

Don't believe so, especially if A/C did not trigger an automatic 42A alternator.