Bob Perkins
January 1, 2013

Correct Fuel Filter
I have a technical question concerning the '66 Mustang's 289 fuel filter. What is the correct finish and Ford part number? Should it have an Autolite or FoMoCo logo? I'm looking for an OEM filter, not a service part.
Via the Internet

The correct Ford part number is C5AZ-9155-B. The engineering number is C5AE-9155-A4 with red Rotunda logo. The filter housing is clear zinc. It's a nice detail item, especially on the 289 High Performance because the filter is visible with the open-element air cleaner installed.

Off-White or Silver Stamping
I now own the 1973 Mach that my dad bought new. I recently restored the original coil as it was getting pretty faded, especially the black. My question concerns the Motorcraft stamp and date code info. According to the Mustang Club of America rule book and several MCA gold card judges, the Motorcraft stamp should be silver or argent in color. The stamp appeared to be off-white on my original coil rather than silver. Do you have an opinion on this?
Jeremy Stein
Via the Internet

It's my opinion that the Motorcraft yellow-top coil used an off-white rather than silver ink for the stamp. Both of my 1973 cars have off-white printing (see photo of NOS example). I can't say for sure that all Motorcraft coils came that way, but most seem to be stamped with the off-white.

Original Regulator?
My 1965 Mustang convertible was built in August 1964 and has the alternator charging system, not the earlier generator. The voltage regulator is FoMoCo rather than an Autolite. I've seen the larger generator-type regulator with the FoMoCo logo but not the smaller alternator regulator. Even though the regulator appears to be original to the car (the screws apparently haven't been removed as the sound deadener on the back of the inner fenders is still intact), I've been told by several judges that it is not correct. Can you help?
Mitch Kelley
Via the Internet

The FoMoCo script voltage regulator is probably original to your car. Very early 1965 alternator-equipped Mustangs had the FoMoCo script regulators.

The regulators were usually date-coded on the back side (see photo with an April 1964 date code). If the screws are covered with sound deadener, I would not remove the regulator to check the date code because that would disturb the unrestored, never-removed-from-the-car documentation.

A FoMoCo logo is not what I consider typical production for 1965 Mustangs with an alternator, but it's definitely acceptable for a car built in August 1964, such as yours.

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