Tech Tip - Alpine - Difficulties with diesel.

By Molly Loomis ,

Winning the battle with diesel grime build-up.

Your long-awaited overseas climbing trip is just a few days away. You’ve packed everything, but what fuel will you use? Clean, easy-to-burn white gas is your best option, but in many parts of the world the creme of the crop isn’t available. Oftentimes, stoves must suffice on the grimiest fuel of all: diesel. Be forewarned! Because of diesel’s high ignition point, and its dirty nature (diesel is a low-grade fuel that, due to limited rounds through the refining process, retains many of its impurities), it’s a pain to use. Not only does it stink and produce a thick black soot — which inevitably ends up all over you and your clothes — it’s difficult to light, cooks inefficiently, and clogs a stove in no time at all. But sometimes it’s all you’ve got. Here are some tips to help get the job done in a quicker and cleaner fashion — the only extra gear that you’ll need to pack is a dedicated diesel-collection pot.

The “super-flush” solution.

Propaganda. Despite what gear company reps may profess, diesel doesn’t burn as efficiently as white gas. Calculate your fuel needs as if you were going to use white gas, and then multiply that number by approximately 1.33 for a fair estimation of the amount of diesel you’ll need. Whenever possible, try and use JP8 diesel (it burns cleaner), and if you’re using a MSR Wisperlite International, swap out your usual shaker jet for the included “K” jet, which has a slightly larger fuel hole, and is less prone to clogging. Filtration. Pour your diesel through a small, tightly woven wire screen (available at a hardware store), or cheesecloth to filter out bits of junk that are undoubtedly in the mix, especially in developing nations. All these small particles add up, clogging your fuel line and your fuel jet. Use your dedicated-diesel pot to collect the excess fuel. Distance matters. Bring along long-stem matches or an “extendo neck” grill lighter to light your stove. Since diesel has a high ignition point, your flame (e.g. a lighter or matches) must be held to the primer fuel longer than with white gas — oftentimes long enough to singe or burn your fingers. These long-stem options will save your fingertips for climbing.Choose wisely. Examine the position of your stove’s spirit cup (the dish where you leak fuel to prime the stove). Again, due to diesel’s high ignition point, using a stove with an easily accessible spirit cup makes a big difference when priming. One easy trick is to cut a narrow strip of cloth from a bandana, soak an end in a fuel bottle, pull out the strip and tear off the saturated section, then place part of the strip in the already-filled spirit cup. Use the bandana strip like a wick to provide better lighting accessibility. Store the excess material in your stove bag.Whistle clean. Clean your stove once a day. Although this may sound excessive, when you’re cooking with dirty fuel this discipline makes a huge difference. After each use, pop out the jet (and shaker needle if applicable) and soak it in a small diesel-filled container. The diesel acts as a solvent and breaks down the carbon build-up, which creates clogs. Make sure that the pin-sized hole in the jet is clean — a sewing needle is a good probing tool for this mission. Every few days do a more thorough cleaning job using a Brillo pad scrap, scrubbing the spirit cup, fuel line, and spreader rings.Ditch the needle. If you’re still having problems and have followed all of the above Beta, ditch your shaker needle. The fuel maybe so contaminated that it can’t flow past the shaker needle, or through the pinpoint hole in the jet.Super flush. This three-part process purges your stove of all its grime. Remove the spirit cup, pop out the generator from the stove body, pull out the wire in the fuel line (jam it back and forth a few times to loosen up any gunk first), and remove the jet and shaker needle, taking care to not lose them. Now, reattach the stove to the fuel bottle as you normally would, and turn it on at normal flow allowing fuel to leak through the dismantled stove — this flow removes debris otherwise difficult to clean. Continue leaking fuel until it flows unobstructed, using your dedicated pot to collect the excess diesel. Now reinsert the wire that runs through the fuel line and repeat the process of leaking fuel until the system flows. Repeat the process again and again reinserting the jet, then the shaker needle. Your stove has now been purged!Don’t forget! Pack the spare parts! Bring along the manufacturer’s recommended repair kit and then some. Imagine if you were to lose any of the repair kit or spare parts — would you be able to make do? Several extra jets, shaker jets, bailing wire, and even an extra generator (for MSR Whisperlites) are indispensable.

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