I am currently selling my collection and I have been putting the stoves that are not working to one side to work on after the working stoves are sold. I have a very disheartening pile of 8Rs and yesterday decided to start on them. I had not noted why they would not work so tried the first one. Often the cause is a blocked burner. Once the tank became pressurized vapour was coming out of the nipple but it refused to light. The vapour was invisible but I could clearly hear it. I turned the stove off and tried to work out what was wrong. I wondered whether there was insufficient vapour to light and decided to pressure test the tank and burner. I have an assortment of adaptors that I have made over the years which I use with a battery powered pump which has an accurate digital pressure gauge. I exchanged the tank lid for my pressure adaptor, pumped the system up to about 30 psi and opened the regulating valve. Fuel cleanly shot out of the nipple which showed that there was an adequate flow of fuel. The tank had Coleman fuel in it and I tried to empty it but you cannot completely empty an 8R tank because the filling tube projects into the tank to prevent overfilling. I then filled the tank with Aspen 4T and the stove lit and burned properly. I wondered whether water had got into the tank so I emptied the tank into a jug. There was no obvious contamination of the fuel. That fuel has been put in the Coleman containers because it is suspect and will be used for flushing tanks out. I have read somewhere that Coleman fuel had a very short shelf life however there is no Use By date on the cans. I have previously used 20 year old Coleman fuel without any bother. I repeated the same procedure on another "non working" 8R with exactly the same result. It appears that Coleman fuel can deteriorate and it may be worth swopping fuels if you have trouble with an 8R lighting when vapour is clearly coming out of the nipple. In future if I have the problem I will blow the defective fuel out of the tank although I have not worked out how to catch it yet. These are some of the pressure adaptors that I have made over the years using discarded tyre valves brazed to various stove fittings From the left back to the front they are a large tank lid, a late petrol stove tank lid, a late paraffin stove small tank lid (the threads on these two do not always fit earlier stoves), an early small tank lid, a pump tube with a filling tube on the end to test small tank lids, a small pump lid to test tanks with the tank lid in position to see if the filling tube top is defective, a plug to seal a pump tube to pressure test the bottom joint before refitting the tube in the tank, a packing box for a 71, 8 or 80 and a packing box for an 8R or 111. The plug for sealing the pump tubes is made out of a pump valve top which was damaged. It has a 10 mm stainless steel nut brazed to the top. I have reclaimed damaged pump valves using the same method and a 1/4" square 10 mm socket slips nicely down the pump tube to fit or remove the pump valve without slipping which makes a nice change. At the time I was experimenting but you could reverse an ordinary pump valve in a pump tube and achieve the same result CAUTION I use a pump with an accurate pressure gauge to do pressure tests. It would be dangerous to use a pump without a pressure gauge as the pressure increases rapidly when testing small tanked stoves such as 96s, 8s, 8Rs, 71s and 80s and when testing tank lids on the pump tube You have to take the valve out of the valve housing before brazing the valve housing to the fitting or you will destroy the seal. Regards Bryan
hi Brian i had similar trouble with a couple of 8r's i imported from the states, to get around it i emptied the tanks and then refilled them with fresh panel wipe and then opened the valve and placed the burner over a gas ring on low heat you could hear the hiss of the old fuel/gas escaping but it wouldn't burn, after a minute or two the old fuel was vaporised out of the wick and the clean fuel caught light the stoves have been fine ever since
Hi: In 40+ years of repairing stoves I have never til now heard of bad Coleman fuel of any age. I have used Coleman fuel that was over 50 yrs. old with great results. I have only seen this problem when appliance was not designed for Coleman fuel or the fuel had been contaminated by other fuels that were in the tank or poor condition of the interior of the tank. Mike..
Wow! Your pressure adapter devices are fantastic, Bryan! Thanks for sharing them. They are definitely going in my fettling notebook of things to do. Cheers, Gary
Hey, Flivver, My experience with Coleman fuel is the same as yours. I've never had a bad batch, unless it got contaminated, some way. I've used Coleman fuel that was VERY old, with superb results. So, I have no idea why Bryan had his problems with it. A head-scratcher, that's for sure. Take care, and God Bless! Every Good Wish, Doc
I have had a very few batches of Coleman go bad over the years. I believe they went bad because of improper storage... A can that might not have been properly sealed. Wide temperature swings in the garage, this leads to the vapor in the can expanding and contracting which causes it to "breathe" air into the can. This can lead to condensation of water. These are my guesses. The result is fuel that has a an odd funky odor. Gasoline and Coleman both have this strange odor when it goes bad. When you smell it you know. I have had this happen in the can and my 8R and a couple Coleman lanterns that got very occasional use with fuel sitting in the tank for years. Bad fuel in the stove/lantern will cause it to burn fitfully, sputter, burn yellow etc, or hardly burn at all. I have NEVER had this problem with an unopened can of Coleman, but have a few times with a partial can. Dumping the fuel and replacing with fresh almost always fixes the problem. Just my experience, Good to see Doc is back. Jim Henderson
The situation regarding my fuel makes little sense. The information about the short shelf life of Colemans fuel was given by a Colemans employee in the 1970s. However if that was correct a Use By date should be clearly stated on the cans and that is not done suggesting that the statement was incorrect. I had two cans of the suspect fuel which were bought separately from the same shop near the end of last year. It is probable that the two cans came from the same manufacturing batch. The shop has only been open about five years so the fuel is unlikely to be old stock. Even more bizarrely fuel from the same tins has been successfully used to test 80s and 71s in the same period without any problem. The problem has only occurred on 8Rs. All pressure stoves work on the same principle. A pressurized fuel tank forces fuel through a heated tube or tubes which boils the liquid fuel into vapour which ignites after it mixes with air. 80s, 71s and 8Rs are very similar except the 8Rs have a horizontal tank with the anti overfill device on it which prevents the tank being emptied completely. I am beginning to wonder whether there has been water in the tanks which has saturated the wick so that pressurized fuel was simply pushing water through the burner and that the "vapourised fuel" coming out of the nipple was actually steam which obviously would not light. The burners are simply tubes and cannot convert inflammable liquid into incombustible vapour. Any volatile liquid exposed to the air will change its character because the more volatile elements of the liquid will evaporate changing the character of the remaining liquid. However this should have little effect on liquids in sealed containers as the evaporated material will simply condense on the inside of the container and drop back into the liquid. The fuel in the 8Rs was sealed in by the tank lid and the regulating valves were closed so theoretically the fuel should not have changed in the stoves. The fuel tins were also tightly closed and whilst there could be slight leakage after the tins were initially opened they were both opened less than 6 months ago. That period does not seem long enough for moisture to gain access to sealed tins. I will try mixing water with the fuel to see if they do mix and will let you know what happens. Water does mix with spirits but I would not expect it to mix with petrols. I started using petrol stoves in 1958 and started repairing them shortly after as the stoves were designed for unleaded petrol and we only had leaded petrol which caused real problems with the burners. Despite having a multitude of different problems I have never come across suspect fuel before. Bill the stoves may have come from the States although I am not certain how that should affect them unless there has been an odd fuel used previously in the stoves. A lot of my petrol stoves were bought from the States as they were a lot cheaper there than here even when taking postage into account Thanks to everyone for their input. Gary if you remove the valve cores from the adaptors you can connect the valves to the water mains and flush petrol stove burners out at mains water pressure. This once solved a mysterious recurring blockage on a 123R burner. Despite "successfully" clearing the inside of the burner several times it repeatedly blocked. The blockages were caused because graphite had leached out of the graphite packing and screwing the regulating needle back into the burner pushed the graphite into the valve and blocked it despite the burner being clear prior to reassembly. Once the graphite was flushed out I realized what was happening and renewed the packing which permanently cured the problem Regards Bryan
I tried adding some fuel to water to see what happens. There was a very odd result. Initially the petrol collected in blobs on the surface so was clearly visible however if left to stand the blobs disappeared and became invisible. If the liquid was then swirled the blobs would reappear only to disappear when the liquid was left to stand. The fuel that I tested was substantially Aspen 4T with a small proportion of Colemans fuel but it appears that you could be use water contaminated fuel without realizing it. I have not tried adding water to the fuel which would result in the water lying as blobs at the bottom of the fuel. However the colour of the water and fuel is very similar so any water blobs would be difficult to see unless you looked very closely If there was water in the fuel it would fall to the bottom of the tank so would be drawn by the wick into the fuel tube which would have the effect that I have been getting Regards Bryan
hi Bryan the water in the fuel would make sense in my case, both the stoves hadn't been used for years when i got them,the fuel in them had a greenish tinge when emptied out, never having bought coleman fuel i assume that is what was in them(or maybe it was discoloured due to being in contact with a brass tank for years), if the wicks had absorbed moisture it would explain why even over a gas burner they wouldn't light maybe it was steam rather than old fuel that i burnt off and once the wicks were cleared of water the fuel started to come through ?
Hi Bill The fuel appears to contain water normally but I am not certain how. I had a full tin of Colemans fuel that developed a pin hole in the bottom. The area around the pinhole on the outside was clean but had a difficult to find pinhole so it must have rusted through from the inside or the outside of the tin would have had rust around the hole. I had the same problem with paint thinners. I used to restore motorcycles and that involved spraying them. A gallon tin of thinners was on a shelf over one of my bikes. I could not understand what was stripping paint off my bike fairing. I had been going into the garage when it was cold so there was no smell and I thought that there was some sort of chemical reaction in the grp which made no sense as the paint had been on it for years. I then went in when it was hot and smelt the thinners. When I examined the can there was a tiny pinhole in the bottom. When it was hot the can got pressurized and the thinners was forced out and dripped off the shelf onto my bike. It seems difficult to believe that two volatile liquids could contain water but both cans rusted from the inside and as far as I know ferrous metals need water to make them rust. Since posting this item I have heard from another collector who had similar problems with Colemans fuel so it appears that it is at least suspect in some circumstances Regards Bryan
Hi I accidentally came across a 1980s Colemans fuel can in the garage. It is shown below just in case you come across old fuel and have reservations about using it The can on the left was bought around about 1980. The one on the right is a modern can bought last year The fitting on the top of the old can is a Colemans spout allowing you to fill stoves with little spillage. I do not know whether they are still available and unfortunately it does not fit modern cans. Regards Bryan
CCS University of all things Stove does it again. Great stuff Brian, very educational to a muggins like me. Glad you appear to have resolved the fuel problem. Since I cannot buy Coleman fuel here in Italy, I use Aspen 4T in my petrol burners, and am very happy with the results. I have an Optimus 111T than performs much better with Aspen than with fuel I use in my paraffin burners. Thanks again for the detailed analysis and resolution of this interesting problem.
Hi John Snowgoose told me about Aspen 4T. It seems ironic that I had been looking for it for over fifty years and then find out about it when I am selling nearly all of my stoves that use it. I think that it was Ross found the Optimus instruction that said that a 111 was for paraffin OR white petrol. I was curious and before I sold my last 111 tried it. The stove gave a really nice flame with the Aspen 4T and if I had been keeping it I would have been tempted to use the 4T instead of paraffin Nice to hear from you Regards Bryan
Hi All I have just remember where I had some untainted old Coleman's fuel so I thought that I would test it to see if there were any problems with it. When I bought the Coleman's fuel around 1980 I used it in my 80s. I stopped using them after a single trip to Glencoe because I fitted panniers to my motorcycle so could carry larger stoves. I filled them up and put them on the shelf so they would be ready for use and forgot about them. The fuel has been sealed in the tank since then. Whilst the flame is not perfect the burner was bought sometime between 1958 and 1960. It has been cleaned out at least once and probably more. Bearing in mind the combination of burner age, its extensive use and the age of the fuel I think that the flame is acceptable. This suggests that any problem with Coleman's fuel is not age related although I would be dubious of using older fuel that had been stored in a steel container because of the possibility of rust contamination. I suddenly realized that whilst I frequently changed or cleaned burners in the 1950s and early 1960s I have never changed the tank lid washer. Bearing in mind the stoves intensive use it is a surprise that it is still functioning about fifty years later Regards Bryan
Coleman Fuel is what used to be called "white gas". It is straight 80-octane gasoline with no additives or dyes, refined from petroleum, distilled purer than run-of-the-mill automotive gasoline. Some 60 years ago and earlier it was common for filling stations to sell white gas from bulk along with regular automotive gasoline. Its shelf life is years, if not decades. My father, who worked for a small, local telephone company in the early 1960s told me the company owner bought white gas in 35-gallon drums for the portable power equipment, because, unlike regular automotive gasoline, it didn't gum up the carburetors if the engines sat idle for weeks to months. Gasoline and water are immiscible, that is, they won't mix, as gasoline is a non-polar fluid and water is a polar fluid. What's more, because Coleman Fuel is water-clear, if there is water in the fuel, it may be hard to see. Water is denser than gasoline, so it will always sink to the bottom of the container. The fluids have a different index of refraction, so if one were to pour it into a clear plastic or glass container, it would be obvious if there's a layer of water at the bottom. How does water get into the fuel? If the container is not hermetically sealed and is less than full, as ambient temperature drops, moist air is sucked into the container. If it gets cool enough, the air-moisture mix will reach the dew point and condensation occurs. Water droplets form and sink to the bottom. Being covered with a layer of gasoline, the water is now trapped and cannot evaporate. Repeat that cycle dozens of times over several months during the cool time of the year, and it is easily possible to find a couple of centimeters of water at the bottom of the container. To prevent this occurring with light planes that may be parked at the airport for a couple of weeks between uses, owners prefer to top up the fuel tanks so less "breathing" occurs, and thus less moist air gets drawn into the fuel tanks. With aviation gasoline, it is easy to see if there's water in the tank, because the different fuel grades have dye in them (red, blue, green) while water is colorless. Jet fuel is water-clear, like Coleman Fuel, but the specific gravity and index of refraction is so different from water that it is obvious in a fuel sample cup whether one has drawn just fuel or fuel contaminated with water.
Coleman Fuel is not the same as white gas and it is around 50-55 octane. White gas was gas without tetraethyl lead added. Gas with was known as Ethyl in advertising. Coleman Fuel is a version of naptha, different from gasoline although both are petroleum distillates. Coleman fuel does contain an anti-rust additive. I has bought gallon cans of CF at estate and garage sales that were known to be 30+ years old. Often the top of the can (which was unpainted from the factory) is covered with a heavy coat of rust. Inside the can looks brand new. Earlier CF was tinted blue. I has often bought lanterns or stoves that have fuel in them from the last time (10, 20, 40 years ago) they were used. Occasionally it is green. the green is usually a darker color than the blue tint so I don't think it is a factory dye. As commented on above when gasoline has been used and has gone bad it has a very distinctive odor. Old CF from a GPA tank does smell a bit different from new CF, but to me not the same as gasoline. Since many have fired up old GPAs full of old fuel and your problem is only with one specific model of GPA I suspect something peculiar to that GPA. The water in the wick theory seems plausible. CF can get contaminated with water but the two don't mix. CF will float on top of the water. It will mix temporarily if agitated. When I buy a GPA with fuel in it I always shake it about and decant it into a clear glass jar and allow it to sit for a day or two. That allows me to see how much rust and other sediment is in the tank and if there is water in it.
