Porsche 914 & 914/6 Combo Gauges (Oil Temperature/Fuel Level)

Porsche^® 914/4 models purchased with the 2.0 Liter engine but without the "Appearance Package" (that included the three-gauge center console) were delivered with an oil temperature/fuel level combination gauge. A similar gauge was standard in all 914/6 models. Why this convenient and vital gauge was not standard equipment (or even available in the 914/4 1.7 and 1.8L models) is a question that will have to go unanswered (like the battery location).  Similar to the fuel gauges, the combination gauges housed indicators for the oil pressure, alternator (marked with a "G" for "generator") and hand brake. Like the speedometer and fuel gauge, the combo gauge case is 100mm in diameter. Combo gauges are not sealed; they can be disassembled via removal of tiny screws on the back enabling removal of the upper and lower plates containing the temp and fuel gauge mechanisms. This design permits fairly easy restoration.  Problems pervasive to all 914 combo gauges include needle fading and lens fogging / scratching, although fogging issues can be fairly easily remedied through removal of the gauge mechanisms and subsequent cleaning.

Current eBay listings for Porsche 914 combo gauges (compare with items on this page to determine year and ensure authenticity - normally, there are no 914 combo gauges listed):

The combo gauge was not available on the 1970-1972 Porsche 914/4 models, as it was associated strictly with the 2.0L cars (either four or six cylinder), and only the 1.7L engine was offered in the 914/4 during these years

The 1973 and very early 1974 Porsche 914 combination gauge is commonly referred to as a "silver button" or "silver center" gauge,  because it has a silver-colored cap in the middle. These units have deep bezel rings, and the earlier units have glass lenses (later units have plastic lenses that are prone to scratching). The temperature range is actually printed on the gauge face, but it is in type too small to read while driving (and is hidden under the rim of the gauge anyway, so to even see it, you must hold the gauge at a severe angle). The range begins at 60 degrees Celsius; the redline begins at 156.7 degrees Celsius (it's a Porsche gauge, so it is exact), and the redline terminates at 200 degrees Celsius (your engine would likely be on fire at this temperature). As the actual gauge sections are easily removable from the housing, you will sometimes see this "silver center" gauge housing fitted with the more common temp gauge section from the later model years. This works fine (and may be preferable from a functionality standpoint), but is not "factory original" (if that is your goal).  As noted above, the silver center combo gauge, part number 914 641 101 30, came only in the 1973 2.0L models in which the popular "Appearance Package" was not ordered, making them extremely rare. As with all "silver button" gauges, the two-piece, painted steel bezel on these units is prone to rust.

The 1974-1976 Porsche 914 combo gauge models are commonly referred to as "black center" gauges, because they have do not have the silver-colored cap found in the earlier style. They have shallow, one-piece, black-painted steel or brass bezel rings and most have plastic lenses that are prone to scratching. Like the 1973 units, the temperature range is illegibly printed on the gauge face, but the scale is different. The range begins at 30 degrees Celsius, and the redline, still beginning at 156.7 degrees Celsius, has shrunk and terminates at 170 degrees Celsius (at which point your engine would be seized, but not actually burning). The later combo gauges, bearing part number 914 641 101 50, came only in the 1974-1976 2.0L models in which the "Appearance Package" was not ordered, making them rare, but more common that the 1973 combo gauges.

The Porsche 914/6 models were all equipped with oil temperature/fuel level combination gauges which are stylistically similar to the 1973 "silver button" style combination gauges. The Porsche 914/6 combo gauge can be either part number 914 641 101 10 or part number 914 641 101 20. The ".10" gauge is not documented in the parts catalog, but it was used in the vast majority of Porsche 914/6 vehicles, with the transition to the ".20" gauge apparently occurring near the end of the 1971 MY production (and actually extending into 1972 MY cars - there does not appear to have been a clear-cut changeover). 

The 914 641 101 10 Porsche 914/6 combo gauges differ from the 1973 914/4 combo gauges (part number 914 641 101 30 described above) in the symbol for the hand brake, the positions of all three warning lights and the entire temp gauge insert. This temperature scale is multicolored and equipped with a warning light (amber section as in the fuel gauge insert. The scale is from 50-66 degrees Celsius in the white-striped warm-up zone, the single white line 66-129 degrees Celsius operating range with a 109.5 degree optimal marker (straight up), 129-144 degree red-striped danger range, followed by the solid red "higher than 144 degrees Celsius - your engine is cooked" range. 

The less-common 914 641 101 20 Porsche 914/6 combo gauges are a logical transition to the 1973 914/4 combo gauges, because they are identical with the exception of the actual temp insert (which is, of course, appropriately scaled for the six cylinder engine). As with all "silver button" gauges, the two-piece, painted steel bezel on these units is prone to rust. Thanks to Wolfgang Scheigher for providing a picture of the ".20" combo gauge from his late 1971 Porsche 914/6!