Northwest Nova

1962 – 67 Chevy II – Nova – Acadian
Parts & Accessories
(541) 788–2191


There were quite a few different gas or "fuel filler" caps used on the Nova in the 1962 - 79 period. Just about all of them are still available in some form (reproduction, aftermarket replacement, AC Delco). The ones that cause the most headaches are the 1962 – 67 caps, followed by confusion over "vented" vs. "not vented" in later years. Here we will attempt to give a brief overview to help you sort them out.

→ 1962 – 67
The original parts books show the 1962 – 67 gas caps as "Nova only", of which there were two different versions. We look at the design differences between the two versions here. The gas caps were painted the car's body color out of the factory. Early replacements came in primer and had to be painted to match the car. GM quickly went to a chrome service replacement, probably to spare mechanics and customers the hassle of having to paint the new cap. The parts books seem to indicate the primer replacement cap was only available for the 1962 – 64 Chevy IIs, we did not come across a listing for 1965 – 67 models.

Originals were a crappy design and known to break. Also easy to steal. Big reason why you rarely see originals in any shape. There were two optional gas caps available from the dealer — a chrome locking gas cap with a raised bowtie center and the "S" handle gas cap, which had an easier to grasp black plastic handle. There is no RPO code for either of these optional gas caps, you do see them advertised in dealer sales literature.

Reproductions are also not of the best quality and can break as well. The chrome ones tend to spot rust quickly if consistently exposed to the elements and not kept properly polished (waxed). You can still find long discontinued period auto parts store replacements at swap meets and eBay. Some fit well, some do not. Visually they can vary wildly and usually do not match the original GM caps.

→ 1968 – 74
1968 and later caps fit other GM cars and are still plentiful. They do not have the quality issues the earlier caps did. Replacement or non–reproduction (i.e. visually not "correct") caps can normally be purchased at auto parts stores. NOS GM ones are usually prevalent on eBay. Purchase an auto parts store unit unless you are building a correct restoration.

In this period the main thing you need to be aware of is vented vs. non–vented gas caps. This is determined by if your car has (had) Evaporative Emission Controls or not. EEC or E.E.C. is a non-vented fuel tank with vapor recovery lines running to a charcoal can (normally in the engine compartment) and then purged to the air cleaner housing or carburetor. The system debuted in 1970 California sold passenger vehicles and was 50 state applicable in 1971. It is important to use correct replacement parts with EEC equipped vehicles to prevent both drivability issues and fuel tank damage. The system does not rob power from the motor and should be kept in place unless heavily modifying the vehicle.

→ 1975 – 79
As with the 3rd gen gas caps, these are a common design that were used on other GM vehicles. They can be found at local auto parts stores and one is still available from AC Delco. All are not vented as all cars had an EEC system of some type by this point.

Year(s) Body Style GM Part # Application Notes
1962—64 ALL 5773583 Primer, non-locking | Part number appears in a single 1964 reference and no other parts book we looked in.Part Reproduced
1962—64 ALL 3792252 Chrome, non–locking | Discontinued 11–1990Part Reproduced
1962—64 ALL 985277 Chrome, locking | Rare part discontinued 03–65
1965—67 ALL 3867853 Chrome, non–locking — Part Reproduced
1965—67 ALL 986191 Chrome, locking | Discontinued 01–68Part Reproduced
1968—69 ALL 3914863 Vented, non–locking | 3997480 supersedes 11–1990, but this is likley incorrect. 3997480 is a 1970 non–Nova EEC cap. 3984552 is another number in the chain suprseeded by 3914863 in 06–1971. Aftermarket manufactuers sell 3914863 as the 1968 – 70 "S" rivet cap (see 3931449 below). Though the '70 cap likely functinally works, we found no evidence of GM superceeding the '68–69 cap with 3931449.Generic Parts Store Replacement Available
1968—69 ALL 987291 Vented, locking | Discontinued 08–1971Generic Parts Store Replacement Available
1970 ALL 3931449 Vented, non–locking, exc. EEC | Very common 1960s "S" rivet GM gas cap that had at least 6 related part numbers. We have seen numerous NOS examples with a black or dark center "S" rivet. Number provided here is the common Nova one.Part Reproduced
1970—74 ALL 410431
413755 Sup. 09–1979
Not vented, non–locking w/ EEC | This is the taller "deep cam" cap for cars with a charcoal can and vapor recovery lines running from the fuel tank. OEM units one handle "ear" often has a hole stamped in it. The GM books are unfortunately vague regarding exact application (i.e. deep cam & not vented). It can be found under multiple numbers, the two common Nova ones listed here. Discontinued 11–1990.Generic Parts Store Replacement Available
1971—74 ALL 994171 Chrome, locking | The books are again vague on exact application, but this is a "deep cam" cap and very likely not vented. Listed as 981837 in some books until 08–1974.Generic Parts Store Replacement Available
1975—77 ALL 560524 Chrome, not vented, non–locking | Common mid 1970s GM gas cap that had at least 3 other part numbers. Discontinued 11–1990.Generic Parts Store Replacement Available
1975—??? ALL 983493 Locking — Bright–dip (zinc?) plated "deep cam" cap. Dealer accessory, we did not come across it in standard parts books.
1978—79 ALL 560585
Non–locking | Bright–dip (zinc?) plated "deep cam" cap.AC Delco Generic Service Replacement Still Available
1962—67 ALL 3792265 Cap handle (chrome)
1962—67 ALL 3792265 Cap handle screw (10–24 x 3/8")

Last updated Jan 19, 2022