After years of experience with a variety of white gas backpacking stoves, I've found the most common maintenance issue to be a clogged fuel jet. Here's how to deal with it.
The fuel jet is the small piece at the base of the stove where the white gas comes out to feed the burner above. Most are nothing more than a small specialized nut with a teeny-tiny hole in the middle that allows small amounts of fuel to come through. If it gets clogged, no fuel can come through and the stove won't work.
Most clogs result from a build-up of fuel residue. White gas burns pretty clean and it usually takes a while before enough residue builds up to be a problem. (Kerosene and unleaded gasoline produce much more residue; stoves designed to burn these fuels typically feature larger holes in the jet to prevent clogging.) Small amounts of grit and debris can also clog the jet as well.
If the jet is clogged, you need an incredible narrow needle or thin piece of wire to unclog it. Many stoves, including most newer models from MSR, incorporate a small piece directly underneath the jet with a tiny needle on its top. It moves up and down when shaken, allowing you to clean the jet by shaking the needle. (This feature is usually called a "shaker jet.")
If this doesn't work, or if your stove lacks a shaker jet, you'll need to manually clear the jet. The point of a safety pin will sometimes work, but what you really want is a specialized jet cleaning tool. Some stove manufacturers include this accessory with the stove; otherwise you'll need to purchase a maintenance kit that includes a jet cleaning tool. For MSR stoves, the jet cleaner only comes with their expedition service kit (pictured)—it's that silver tool in the lower right, with two tiny wires protruding from the end.
Also make sure that you can remove the jet from the stove in the field if necessary. Some jets unscrew with just a flathead screwdriver; others need a small nut tool to unscrew them. Stoves usually come with a tiny lightweight tool for loosening and tightening all the parts, including the jet.
“Equipped” is an AMC Outdoors blog, written by Matt Heid.