Just checking my Omnifuel II stove before my trip. It works but it's making a chugging sound. I originally suspected old gas. I am using two year old Coleman fuel. But I also took apart the gas control spindle and the condition of the O-ring is terrible - big chunk missing. Now I'm thinking the chugging sound could be from air being suck in through a gap caused by the deteriorated O-ring.

The problem I have is that I cannot obtain the service kit for this stove locally and maybe not in time for my trip in two weeks.

If this was you, would you just get an aftermarket gasket with the same dimensions?

Go to a farm implement store, or a heavy equipment dealership, or even an old time hardware store. They sell all sizes of o-rings from tiny to huge. As a heavy construction mechanic for 42 years I would often need to go buy o-rings for equipment repair.

Bring your old o-ring with you and ask for a Viton o-ring of the same size diameter, and same size of the o-ring itself. Viton is what you want because it works better in fuels and oils. If you can’t find Viton o=rings, Regular o-rings made of rubber will get you through a trip, but then you will want the correct material.

For installation put a dab of silicone synthetic grease on the o-ring spindle and the o-ring.

Thanks SV. I emailed the US distributor and a sympathetic customer service agent just dropped one in the mail for me.

Glad you have one on the way. I was going to warn you about standard rubber o-rings and gaskets degrading quickly and gumming up the works. Good advice above about using Viton which will last longer when exposed to fuel. One of my first stove rebuilding projects was a stove where the fuel cap gasket had aged, and previous owner had replaced it with what was probably a stock general-purpose gasket. It worked at first, then left me stranded in the Grand Canyon on a winter backpacking trip because it would not hold pressure. After I got the right replacement part, and cleaned up the gunk left by the wrong gasket, the stove has worked flawlessly.

I got a nitrile rubber one from an autobody shop and it works but I'll swap it out when I get the OEM. I read the nitrile rubber is suitable for petroleum applications.

Anyway, it now runs smoothly proving the chugging was caused by the bad o-ring and not old Coleman fuel (container opened two years ago).

Old gas is seldom the cause. Crown and Coleman fuels are filtered and refined to provide a stable long storage fuel. An air leak is far more likely. Chugging can also simply be a mismatch in the supply pressure.

Primus does sell maintanence kits $25, but my favorite source for stove parts is Needle Sports who carries a large selection of Primus and MSR parts.

butthead

butthead: "Old gas is seldom the cause. Crown and Coleman fuels are filtered and refined to provide a stable long storage fuel. An air leak is far more likely. Chugging can also simply be a mismatch in the supply pressure.


Primus does sell maintanence kits $25, but my favorite source for stove parts is Needle Sports who carries a large selection of Primus and MSR parts.


butthead"

Thanks butthead. The broader issue is the relative scarcity of specialty products available in Canada for a variety of reasons - distribution agreements, legal restrictions, and more generally a difference in national consumer cultures. So when it comes to a variety of products discussed on this chat group that I've come to possess, I've had to beat the bushes hard or shop State-side which is significantly more expensive.

Permithrine - can't get it here
Dynema - hard to find
Hammock choice and attendant accessories - limited and hard to find.
Denatured alcohol in limited sizes - forget it.
Primus maintenance kit - finally found one available from an online distributor I thought was in Canada but may be American (trying to distinguish between Canadian and American commercial web pages is a PITA in Canada. Sometimes the price looks too good to be true, then you realize it's a US operation in $US. That's a whole different issue). MEC carries my stove but doesn't carry the maintenance kit.

That's a sample. Oh, but if you want marijuana or codeine...that we have.

But having said all of that you live in the land of plenty but your link references a UK website. That's interesting.

As a collector of MSR stoves I searched long for a source. In the USA MSR supports only factory repairs/rebuilds. Want to use XKG jets in a Dragonfly? You need to do it on your own and if such a stove goes to MSR all non stock parts will be replaced.
I not only collect but experiment with mine.

I will suggest alternative descriptions for alcohol, Heat gas line antifreeze is a very good fuel and available in ethyl alcohol and methyl varieties. Marine stove fuels often methyl alcohol so maybe a marina could supply you.

butthead

butthead: "As a collector of MSR stoves I searched long for a source. In the USA MSR supports only factory repairs/rebuilds. Want to use XKG jets in a Dragonfly? You need to do it on your own and if such a stove goes to MSR all non stock parts will be replaced.
I not only collect but experiment with mine.

I will suggest alternative descriptions for alcohol, Heat gas line antifreeze is a very good fuel and available in ethyl alcohol and methyl varieties. Marine stove fuels often methyl alcohol so maybe a marina could supply you.


butthead"

Heet in the yellow bottle...yes that came up in my research as the leading contender. Only available at Amazon.ca for about $20 and may not be shipped in time for my trip.

Curious about your reservation regarding methyl hydrate? Several reports online suggest it although there are warnings about toxic fumes. But we'll always be using it in the outdoors so I'm not concerned about that. I tried it already and it worked perfectly - very clean burning too.

Our Swedish alcohol stove lists the various suitable products by country for cooking. Methyl hydrate is on the list for Canada but not denatured alcohol (which is on the USA list). Ethanol products are favoured over Methanol for heat but produce more soot. As soot is what we are trying to avoid in the priming process, methanol derivatives would be better no?

Appreciate your input. Thx.

P.S. Out of curiosity, how many MSR stoves do you own?

Last count about 20, 12 laid out for a photo. Duplicates and some triples of Whisperlites/Dragonflies/XKGs/Simmerlites/WindPros. Just in the MSR set, other brands come in and go out, liquid fuel/canister/DIY alcohol/DIY twig.
Old MSR Firefly I resurrected shown with a BerniDawg Midi-cap.

"Curious about your reservation regarding methyl hydrate?" None, just a mention of toxicity for those who refuse to do proper diligence. Ethanol is often mixed with other stuff hence the smoke. Methyl hydrate, methanol, methyl alcohol, all names for the same thing and vary with countries usage, similar to the English terms for white gasoline, naphtha.

butthead