Problems with Pocket Rocket

We had problems with our MSR Pocket Rocket today. It was quite cold and windy out, but we did seek out a sheltered spot. Usually, water comes to a boil rapidly. It took a very long time to get the water to just warm up. The "whooshing" sound that usually comes from the stove was absent as well. We were using the MSR Isobutane-Propane fuel.

Has anyone else had this problem with the Pocket Rocket? Can anyone suggest a different fuel that maybe performs better under cold conditions?

By the by, the stove works fine now that we are back home....

from what I understand most iso-butane-propane stoves have trouble in the cold. I have never personally used my p-r in winter seeing how this is my first winter I have decided to winter hike, but I have a dragonfly, white fuel powered stove I will use when I need a stove for winter.

All the butane mix canisters will have a problem with low vapor pressure with a temperatur much below 40 degrees. The MSR fuel should have the best low temperature performance due to the propane and isobutane content. I have been meaning to get pressure-temperature measurements for the diffrent fuels, but I have not figured out what threads are used on the canisters.

Ian

I agree with imarchant.Also try packing your canister in such a way that you are preheating it with your body heat(in pack next to back)

I have used my p-r down to about 20 degrees without to much problems, had to warm up the canister once but it worked fineafter that.

suggestion...JETBOIL

The pocket rocket is very sensitive to wind.

So protect against the wind and warm the canister in your sleeping bag. I've done well with them down into the 20's.

My Primus is very similar. We used it down into the 20's. Best results were to warm it in the bag, often supplement with some barehand warming as we near-boiled a bit of water, then nested the cannister in the hot water for boiling our larger amounts for breakfast and such. A big difference in heat output between the two methods. The hot water bath lasted for our entire cooking needs.

I have a heat packet in a doubled up ziploc container experiment I'll be trying later this winter and will report back with the results ... if it doesn't blow my head off!

One thing I and others have noticed is that the vaporization of the fuel varies with the amount of fuel in the tank. As the tank gets emptier, the stove doesnt perform as well in cooler temps. With some care, a heat deflector can be built to reflect heat down towards the cannister to help vaporization, but the same shield can also overheat the cannister (which is defintely not a good thing). I use a shield like the one supplied by MSR on their hanging version of the pocket rocket and along with better fuel efficiency and breeze performance, it also tends to heat up the cannister a bit.

Sherpa John said:

suggestion...JETBOIL

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Its been widely reported here that the Jetboil does not perform well in very cold weather, just like most canister stoves.

I use a Primus stove year round,but you have to use all the tricks to make it work. Just started using the Primus 4 season fuel,but I'm not impressed. Primus seems to light easier than MSR.
About a half hour before you stop on the trail,toss a cannister inside your jacket.
If it's not too cold(below 20) wrap your hands around the cannister to warm it,then as soon as it lights wrap a windscreen around it to push the heat down to the cannister. Make sure the cannister doesn't over heat this way!
Toss a cannister in your sleeping bag at night.
Put a mousepad under the cannister to insulate it from the ground or snow.
Put a handwarmer pack under the cannister.
A full cannister maintaines pressure,and is easier to light than a partial. I retire my partial cannisters for use with a lantern,where full pressure isn't needed.
Carry a thermos of hot water to warm the cannister,then use the water to prime the pan for snowmelt. Then fill the thermos with hot soup for later.

As others have noted, canister stoves are generally poor performers in cold weather. Worse still, expansion of the fuel leaving the canister is an endothermic process, which causes the canister to chill even further (assuming no heat reflector is used, of course).

Another major issue with using canister stoves in cold weather is their tendency to flare up when moved or tipped. The movement causes liquid fuel to get caught up in the stream of gas leaving the cylinder and can create quite a fireball. Be very, very careful if using a canister stove in a tent vestibule (or inside the tent, for those who dare). Always be ready to pitch it out the door if necessary!

One reported trick, I haven't actually tried it, is to take a standard electrical guage copper wire, and wrap it around the cannister. Leave one end in the flame. The copper wire will heat up, surrounding the can, and thereby heat it up.

Sounds reasonable. Don't know if it truly works or not.

This is the reason I have a cannister stove for summer travel and use the Whisperlite for winter.

I love my Pocket Rocket... most of the year. Due to it's poor performance in cold temps, I've gone back to my Whisperlite for cold-weather use.

One reported trick, I haven't actually tried it, is to take a standard electrical guage copper wire, and wrap it around the cannister. Leave one end in the flame. The copper wire will heat up, surrounding the can, and thereby heat it up.

Click to expand...

This is a trick I have used for years down to the sub zero temps. It works only when the unit is burning properly. To start, the canister must be at a good working temperature to start (keep it in your sleeping bag, etc.). Cooper has a high conductivity to transfer heat. I made a spiral of wire around the canister (8-10 turns) leaving both ends to pass through the flame. To help the process I took an MSR heat sheild and cut it down to wrap around the copper wire and canister. Sounds like a lot, but once made, it works well.

Pocket rocket in the summer and fall. XGK in the winter.
Last winter I brought my pocket rocket to Baxter because I figured the cabin had a woodstove and it would be warm enough to work effectively. Nope. Of course it was -48 outside, so it took a bit of effort to keep the cabin warm. Lesson learned.

Some interesting data on canister fuels...

http://www.adventurenetwork.com/cgi-bin/adventurenetwork/Propane_Butane.html

Check this site out, you may be surprised how your canister fuel actually works at different temps.

A cheap alternative in winter...

Denatured alcohol stove w/wind screen assembley. You can make one (pepsi can) or you can buy one (works much better). I have a trangia 25 - Trangia Stove Site

It is also very lightwieght!