Of these two Optimus Nova+’s, I know that prior to my owning it one had been primed and fuelled exclusively on pump gasoline. The other has benefitted from alcohol priming and Coleman fuel or, in my ownership, Aspen 4. Similar age, Swedish-made with CEJN fuel pump coupling. Flame plates removed for photography. How it should be … The effect of the additives in pump gasoline - note the chemical erosion of the heat exchanger fins, distortion too from the hot-spots the erosion has created. … and on the outside of the burner bell, extensive pitting as a result of the pump gasoline primes. A measure of the distortion of the burner bell and heat exchanger fins can be seen in the gaps around the circumference of a BD silent burner converter cap. … which consequently cannot be expected to sit properly in the burner bell. On the undamaged Nova the cap fits as it should of course. It’s an issue that is relevant to stove burner damage related in threads such as THIS one. John
Again - a good posting John, thank you. As “seeing is believing” for many of us - This is good proof for why pump gasoline should only be used in dire need in stoves like this.
Thanks for your photos and post. Personally, the critic thing I hate the motor gasoline for stoves & lanterns - the smell. That Smell makes me insane. Kero smell makes me high
Indeed it is. So it looks like the deposits from auto fuel don’t just build up and cause clogging; they actually corrode the metal. Great comparison! ….Arch
The corrosion reminds me of the reports of formic acid attacks car engines when methanol (generates from combustion in certain conditions) was used as a fuel additive rather than ethanol. Of course car engines have a different (high pressure/non atmospheric conditions)combustion environment but something is eating the brass up.
I'm going to point out that there is so much about this we don't know........perhaps the "worn" stove has been run ten times as long? Or at full blast longer than the other? To make any real conclusions that the RUG caused the corrosion one would need to run several diff stoves under identical conditions, some with RUG some with CF, and then compare.
Well, I knew both the fellows who passed them on to me and - following robust questioning (!) - I can confirm that their stoves had very comparable usage, bar the fuel used and priming on alcohol rather than pump gasoline, which would have been unleaded 95 octane in the UK.
John (@presscall ) Brilliant post, which VERY clearly illustrates why using pump gasoline, whilst it may be "convenient", can (and probably will) damage the metal in your stoves!! CRIKEY!! For as long as I've been a member here, most of us have warned newbies NOT to use pump gasoline in their stoves, and most certainly NOT to prime with that noxious stuff??!! And, yet, we have seemingly intelligent new folks say that use pump gasoline, and "it's not hurt my stove, at all", until it DOES!! Then, it's too late for that particular stove, most of the time. Excellent examples of why our advice is spot on the money, John!! I hope the new folks will take heed, and STOP using pump gasoline "because it's convenient", and begin treating their stoves like the wonderful little machines that they are!! Thank you, very sincerely, my friend, for an excellent post, which SHOULD show the newbies WHY they should not continue to use pump gasoline, in appliances that were simply not meant burn it. Sticking to the proper fuels was, is, and always will be the proper course of action. Learning that lesson can be very hard, for those who don't give it their full attention! Take care, and God Bless! Every Good Wish, Mark PS - John, I hope you don't mind, but I posted a note in the thread about the Universal fuel line being corroded, and breaking. I hope that the poster will see your excellent comments and photos here, buy a new stove, and use proper fuels, instead of pump gasoline!
You are, of course, correct. John’s @presscall observations do not prove the damage was caused by pump gasoline. To do that, you would have to take numerous stoves from the same production batch, run a bunch on pump gas, another bunch on CF, and keep a control bunch unused over a period of years. Not something we’re likely to do. John’s observations are an indication of different rates of corrosion, with possible correlation to fuel type. Given that we know that additives in pump gas reduce combustibility of the fuel (because that’s what they’re designed to do), it makes sense that they will leave deposits. These deposits are undesirable, even in high compression engines, which is why pump fuel also includes detergents. And it’s not unlikely that some of the substances produced by burning would be corrosive. So John’s observations are more of a cautionary tale. If you use pump gas consistently in your stoves, you can expect increased wear. Disclaimer: I have used pump gasoline in campstoves — usually a MSR XGK — when long distance hiking. At some resupply points it was the only choice. I always used CF (or equivalent) when I could get it. (In Mexico, much to my surprise, I was able to buy CF in a gin bottle from a vendor — the surplus of a previous climber.) ….Arch
@kerophile George, I used the term ‘chemical erosion’ in my report, realising that with two stoves of the same type and extent of use only the type of fuel and priming fuel used separated them. As a former metallurgist by profession, can you throw light on the viability of my hypothesis? Maybe ‘corrosion’ by the petrol additive deposits would have been a more accurate term for what occurred? Regards, John
The Coleman Stove - The Pros and Cons and Why we Cook on Gasoline This is an interesting anecdote about burning pump gas in places where it was the only option. The main theme is that they used a Coleman suitcase with its large straight generator. They cleaned it regularly. Personally, I have never burned auto petrol in a stove or lantern and I hope I never have to. Crown gas and Coleman gas behave so beautifully in my stoves. However, I have very good access to the fuels of my choice, including white gas, K1 kerosene, and ethanol. Brad
Hi @presscall I do not know the composition of neither the burner head nor the cocktail of additives present in the burning fuel. However I think it reasonable to assume that the burner has suffered significant damage as the result of corrosion/erosion in the flame zone. In operation we have high temperatures, high pressures and velocities, and likely reactive chemical species. There is also temperature cycling between operation and rest, so any protective oxides that might form on the metal surface will be regularly disrupted…. Stove burners have an arduous duty cycle under harsh conditions so best to stick to recommended fuels (or suffer the consequences). Best Regards, Kerophile.
I have to admit, I've run gallons of pump gas in my Coleman stuff. Never had an issue anything like this. I'm since reformed, white gas only, except for the kero converted models of course.