Dealing With Pin Retainers

Most modern ignition locks fall into two broad categories: pin-retained locks and locks that are held in place by an “active retainer.” Active retainer locks have a retainer that is usually spring-loaded, and can generally be released only after the lock has been turned from the Locked position to a particular position.

Most locksmiths would rather deal with ten active retainers than one pin retainer. You generally have to fight, curse, and dig the pin retainers out their sockets, all while assuming painful positions under the dash. So naturally, this article is about the various kinds of pin retainers and how to deal with them as efficiently and painlessly as possible.

Why do manufacturers use pin retainers?

There are generally two types of pin retainers: those that can be driven completely through whatever they are retaining and those that are driven into a “blind” socket, where only one end of the pin is accessible. Any time you see a “blind” pin retained lock, think of it as a “No Trespassing” sign posted by the lock manufacturer. The manufacturer never intended for anyone to remove that pin. The manufacturer intended for the entire lock to be replaced rather than serviced.

Unfortunately, some manufactures forget to take the real world into account while designing locks. They never ask themselves what would happen if the owner loses the key in the middle of the night, or on a holiday weekend, or simply can’t afford to pay for towing the car to a dealership and having the dealer replace the lock. They also assume that the locks will not fail before the cost of replacing the lock exceeds the value of the car.

Locksmiths have to deal with the real world situations that the manufacturers either did not foresee or simply didn’t care about. We get the dirty job of working on things that weren’t designed to be serviced and fixing things that weren’t supposed to break. These operations often require us to remove pin retainers that were never designed to be removed, and that is why we make the “Big Bucks.” Or, at least that is why we should make the big bucks!

Types of Pin Retainers: In order to work properly, a pin retainer has to stay in its socket for the life of the lock. To accomplish this, various methods are used to keep the pin tightly in place after they are installed, and we can classify the different types of pins by the way they are held in place.

Solid / Tapered Pins: As the name implies, a solid pin (photo 1) is essentially a solid rod that is driven into a socket (hole) in the lock housing to hold two or more parts together (usually the ignition lock). In order to make sure that the pin remains firmly in place, the hole is drilled or cast slightly undersized and the pin is forced into the hole under pressure. To make sure that the pin can be started into the hole easily, the ends of the pin are usually tapered. In some cases the entire pin may be tapered as well, but this type of pin is almost never found in an automotive application. A good example of a solid or tapered pin is found on many Toyota and Lexus locks as shown in photo 2.

Splined Pins: A splined pin (photo 3) is also a solid pin, but instead of having smooth sides, it has a series of splines running the length of the pin. These splines dig into the relatively soft metal of the lock and housing, usually cast zinc, to tightly hold the pin in place. Generally, splined pins and tapered pins are interchangeable and can usually be removed with the same techniques. The solid pins used on the Toyota locks that I mentioned above may or may not have splines.

Roll Pins: Roll pins, sometimes referred to as tension pins, are made from a flat piece of spring steel that has been rolled into a cylinder in order to form the pin. Once again, roll pins are inserted under pressure into a slightly undersized hole, but in this case, the roll of spring steel is compressed and the compression of the spring holds the pin in place. Both ends of the pin are tapered so that the pin can be easily started into the hole.