Found this while perusing my favorite reloading supply website. It listed as coming soon. http://www.midwayusa.com/product/348124/msr-arctic-camp-stove-liquid-fuel-pump Has anyone else heard rumors about this pump??
First I've heard of it. Certainly useful in concept. I've never had problems with any of the MSR pumps below freezing -- except of course for the o-ring where the fuel tube connects. (The fuel tube must be lubricated every time before insertion, and even then the o-ring has a limited life.) Interesting that this new pump is intended for use only below freezing. ....Arch
I imagine it has to do with soft O-rings. Most of my MSR pumps are fine. The metal ones are heavy and the check valve on them can fail. They did have a couple models that are best to avoid. Duane
There is nothing on the Cascade Designs website about this model of pump. But, they cost more than the standard pump. Is this done by a company aftermarket? Arch said: Midway quote: Backcountry.com quote: Seems a failure/leak is eminent if used above freezing.
Just thinking, they would have a much smaller market, not all venture out when it gets that cold. Duane
Since it appears that MSR ackowleges there is a problem in cold temps -- it would be nice to know how cold is too cold for the standard pumps. Certainly it is well below freezing. But what is it? I do remember reading an article (can't remember where of course) where some small group had two MSR stoves (one as a back-up) and both pumps would leak fuel when it got really-really cold. They claim they had worked perfectly in warmer weather. They continued to use them with frequently pumping. As I remember it they were using white gas so apparently the pumps/bottle never caught fire but there was no mention of what precautions they were taking.
Sure, no problem. http://www.midwayusa.com/product/348124/msr-arctic-camp-stove-liquid-fuel-pump It is implied by the fact they are trying to sell a fix.
It's not the pump, it's the material the standard pumps use for the O-rings. Dont know what type of O-ring MSR uses. Viton and nitrile have different temperature characteristics. Viton works best in warmer temps, nitrile better in cooler temps. I'd have to look up those temperature ranges. Viton handles fuels better over a longer time frame. Duane
@hikerduane Is that what MSR is saying? If so, couldn't they just sell an extreme-cold-weather seal kit? Retorical question; but seriously, the o-ring kit would cost $39 (vs $49 for the pump) and the profit margin would be larger. @snowcamper Am I being too cynical?
MSR did make a service kit for the Norwegian Army that included the blue seal and ditto o-rings. I recently got hold of - and just passed on to a domestic scout group, some kits that were left over from a major procurement by the NA. As a curiosity, I had them listed on ebay for almost a week at a very reasonable price (compaired to the std kit) with no interest at all. In principle these seals and o-rings should be avaliable from MSR. The reason for not using the blue seals in temp above 0C is that they then will wear more rapidly.
In general. Blue does not mean low temp seal IIRC. Doing some searching, not too in depth, it does not look like Viton is the best low temp choice. One site suggested silicone/fluorosilicone. This would be a whole different thread.
@itchy, My own thoughts and info gathered from looking for spare O-rings from time to time. It would be quite a bit of trouble to measure for the right size O-ring for pumps. I've used many of my MSR stoves in cold weather, even below zero F. My earlier experiences were with my old MSR Intl. One could rig up one pump with cold weather O-rings. I located a good source for O-rings over a year ago for my KAP Arctic stove. Of all names, called The O-ring Store, an online store in the USA. Duane