@ting wong, all, ...A question was asked here: … using Coleman 550B (loving it), but am really worried by the tank getting hot! Too hot to touch even, especially the top of the tank down to the slopes, but the sides and bottom are okay. Should I be too worried, eg, will it catch fire, or worse still, explode??? A worthy topic, I've taken liberty to start it's own thread. 550s will be too hot to touch once they're cooking and fully heated-up and it is a model that is overheated often enough (search for used ones will find many melted knobs). Although I've not heard of a single explosion (so that should not be your concern), if you're using CF/panel wipe, plenty have had sizable flare-ups. Fire is a concern. In the above link credit Brad's excellent 550B comment: 550B is an easy starting stove, burns hot, and simmers well. The single control is a bit close to the burner and so requires care to not burn yourself. Being a newer stove, it has more plastic than the older Colemans, but it is also much lighter for backpacking. The control is not particularly smooth, but with a bit of care it is easily adjusted from hot to simmer. The control might seem backward since it is full high when you first turn it on and then goes toward simmer as you continue to turn. To burn kerosene you must change the generator to a different one than is used to burn white gas, but that change is easy and fast. --------------------------------------- credit bajabum: Great stove, but the control knob is rather close to the hot bits, and as I have "Fat Finger Syndrome", I use an extension made from a bit of alu tubing to reach in there. --------------------------------------- Is 550B getting too hot? it's a good question. Fully heated, cooking on high you must keep close eye on your stove, in case of 550s, eye the plastic control knob. The Coleman 550 instr. or warning fall short of answering this, imo (too vague): > "When stove is in use, all metal parts of the burner assembly and controls, become extremely hot. DO NOT TOUCH" ...<--- only now occurring to me how lame that instruction is, do not touch the flame control, right. Users do manage to control flame, some better than others. Knob: very hot, for some maybe too hot to touch = normal. Knob: beginning to melt = it's overheating, remove pan, that setup overheated the stove. and > "Never place heavy or large capacity utensils on stove." <-- vague (what is too large or too heavy?). My comments: It also matters type of pan and type of cooking: frying in a cast iron / steel pan will contribute to overheating. Aluminum pans are much less of an issue in that regard. Too large?..if using an aluminum pot no more than 8" diameter around, the stove should not overheat. "Frying" in a steel or cast iron pan (esp if it is larger than 8") can result in overheating. Too heavy?... 550 tops are uniquely fragile (support is thin aluminum): Fry pan, we've already warned against pan greater than 8". Pot I would be leery as you try pots bigger than 2 liter. I'd guess 3 liter may be too big / too heavy. 550s have a plastic adjustment knob (often melted). During "normal use" this knob should not be starting to melt, if it starting to melt, remove pot and make a change because at that point you are overheating your 550B. Conversely, although very hot, if knob is not starting to melt, maybe yours is very hot but not to point of too hot? Air on the side of caution.
Some like to criticize the 550B for being unable to handle heavy, large pots and pans. The stove was designed to be a lightweight stove to carry in a pack or pannier. If we can accept that a large pan will overheat a Svea 123 or Optimus 8R, why do we fault the 550B, which can handle larger, heavier stoves than either of those two? The biggest problem with the 550B, in my opinion, is inconsistency. I have a couple that behave splendidly. I also have a couple that lose pressure a bit too fast, in spite of replacing every o ring and cap gasket. The valve to tank seal is by o ring and I have played with the number of turns, four or five, to see if that helps. I have even, on one, tried a sealant, to no avail. These “leaking” ones are still quite usable but require a bit more pumping in use. They also lose pressure overnight, unlike most Coleman stoves and lanterns that can maintain pressure in storage for months.
It's a given that any pressurized fuel stove should not lose pressure. I'd empty the stove's fount, pump it full of air, and use soapy water to find the leaks... and then fix them. If I had to I'd put that empty, pressurized stove under water in a bathtub, sink, or bin to see the stream of bubbles. One thing I've learned as an engineer is to not ignore anomalies... things that happen that aren't supposed to happen. That's how NASA lost two space shuttles... and not ignoring anomalies is why the US Navy has never had a nuclear reactor incident on a ship or sub resulting in death, serious injury, or radiation release. When in doubt, they shut it down and figure out why instead of hoping it isn't serious. Good rule to follow.
First off, thanks for starting this new thread. I was (and probably still am) worried, panic-striken even when I first used it only a couple of weeks back for cooking (which I love), so I do spend inordinately longer time on it, I guess. Apologies to you veterans of this stove as I've only just come back to camping and ebike touring after 3 decades of absence, hahaha. If I may quote John Clifford's (engineer) explanation, which I find reasonable: "If you think about how the Svea 123 stove works, with fuel burning on top of the fount to heat the fuel inside and increase pressure in lieu of a generator as on the 550B, I don't think the heat is excessive. If anything, it will increase the pressure inside the tank without having to pump it. I could see making up a replacement collar comprised of two cylinders with a separate plate/disk with some small holes in it to shield the fount from some of the burner's radiant heat, but I don't think it's necessary. I don't think the temperature is above the flash point of Coleman fuel much less anything else like kero or gasoline/petrol." I feel reassured, but still relatively uneasy thinking that it's getting hotter the longer I use it! When you compare with the other Coleman stoves (which all have I think the plenum at the bottom), I think only the 550 series (was there ever an A version?) stoves have the plenum on top with the generator tip going straight into the chamber, which partly or mainly (sorry, I'm not a trained engineer) explains why it simmers so superbly well great for cooking on the road! And it's bc of this absence of 'mass of metal' to absorb the heat that causes it to radiate its heat on to the tank. And also I notice the distance between the tank and whole burning assembly is much shorter, which doesn't help either. So, in my non-technical way of thinking, I drilled holes in the aluminium collar thinking/hoping some/more ventilation may ease the situation. TBH, I can't tell! About the alu collar and its weight bearing ability, it's an issue for me bc the tabs are already bending to the point of collapsing. And I've seen this happened to some 550Bs. So, in another thread, I found a possible solution in replacing it with a stainless steel mousse mold which fortuitously measures rather close to the original, just needing to chop a little bit off that's all and drill holes. I reckon it will improve it's weight bearing performance and will possibly absorb a bit more heat. Re the plastic knob, mine was already pretty badly melted when I got it and bc it wasn't functioning anyway, I decided to carve it down to bare minimum (see photo) and re-positioned it to the 6 o'clock position. It's a little farther away from the heat now, which helps. The extra turn also prevents it from leaking which I suspect was a problem for previous owners.
Could your 550B that leak be losing pressure through the check valve/pump assembly? The rotating shaft inside the pump is meant to be a backup to the check valve. I had a sticking check valve on a 442 and pulled the pump assembly out and dribbled some Seafoam down in there (could have used carb cleaner as well but this way got the lubrication from the light kero in Seafoam along with the solvents), let it sit for 10 minutes, then pumped it through the valve. No problems since.
As long as it's the right diameter, the right height (so the generator assembly fits unmodified), and you drill enough holes for the burner's airflow and to get cross-ventilation, you should be okay. To me, the ultimate design would have sections placed inside to shield the tank top from reflective heat... but that is probably overkill and unnecessary. I'm looking for a section of aluminum tubing that I can turn down and then drill holes in... that will be good enough (don't need stainless).
Learn from the design of the original collar. Many are crushed is a sad truth but this is due to a mishap or misuse not from normal use. The Coleman Toronto design team are 2nd to none. As sold it's an excellent stove that (like many) requires users to be careful and alert when in-use. The 550 design was tweaked, including burner, after 1st model had shipped. This tells me: after tweaks were completed, by the time the 550B came out, Toronto was satisfied with latest design (your version) -and- because tweaks / minor changes improved it, conversely this may increase odds of your minor changes potentially having an unintended consequence? and maybe not. The collar is a Toronto design: IIRC the original collar can be installed right way up or down, matters not. The dentil type edge (top and bottom) is a weak point : ( but by-design it also reduces the surface-to-surface connection by half, this reduces thermal conductivity from burner to top of tank. Aluminum collar vs steel also not as strong but also reduces this thermal conductivity. To what effect, is this needed during normal use? I don't know. It is possible the excessive heat is only an issue in confined space, extremely hot climate or with little or no wind? or if too hot or too large a pan is atop. TMI, I've been faced with your same problem. A section of brass drain pipe was perfect "fit", which I hastily used. With same concern, I have set that aside hoping to eventually source a piece of aluminum pipe (patio umbrella pole?). -or- somehow reinforce the original aluminum collar, maybe 3 aluminum uprights? held in place.
Aluminum makes for a good radiator. I would think that a thin tube, thicker than the factory, but solid instead of made from a tack-welded strip of aluminum, with scalloped edges top and bottom and holes through it, would not be much heavier while being much stronger. I just ordered some 2" OD 1/16" thick 6061-T6... will attempt to make a replacement spacer. More so for strength than for heat resistance. I think the reason people melt knobs and deform the collar on these stoves is that they're using pans and pots meant for the kitchen instead of the campground on them. That was okay with stoves like the 502, and even the 508/533 and 400-series... but not the 550B. Use light stainless, aluminum, or Ti pots and pans that are the diameter of the windscreen or smaller and I think you'll be fine. The bigger pots and pans will radiate/reflect heat down towards the stove itself, melting knobs and perhaps overheating the fount.
