Hi All, Just wondering if anyone can advise me regarding a problem I have with my Optimus 111c. I've owned it a couple of months and run it a few times. It runs fine at 'full throttle' but when I reduce it to a low simmer it always emits a pop after a minute or so at simmer and starts to underburn. Today I stripped the burner down and cleaned it in an ultrasound bath (all appeared well with the burner and it came up nice and clean) but upon reassembly and testing, it still underburns when set to a low simmer. I'm at a loss to work out what's wrong, but there again I don't know what actually causes underburning! If anyone has any ideas what might be wrong, I'd appreciate any advice. many thanks Matt P.S. (All testing so far has been on white gas (panel wipe) - I wonder if kero would be less prone to underburning?)
Hi Matt I have some 111s, both roarer and silent and also a 111B, but I don't have a 111C. From members who will no doubt put you right, all I have ever seen about the 111C is that it does not burn well. I always think, "Surely it can't be that bad?" I am sure members will give you all the facts.
I have one 111C, and it works well with kero. But I have experienced a similar condition with a classic brass pressure stove. I replaced the silent burner on Primus 5, because it developed a pinhole. The new burner began to develop the underburn at low setting. I changed at random inspiration the inner and out cap from the original burner, and it seemed to have solved the problem. Maybe you could try getting a new pair of inner and outer burner domes, and see what combo would produce the best result. At worst, you would have a spare.
could it have something to do with the position of the choke assembly? I know that i got underburn with my 111t when i ran it on meths with the wrong jet and without the restrictor tube... it seems to me that the restrictor tube on the 111t and the choke on the 111c do similar things...
This is interesting - my 111c doesn't have a choke (in fact the burner doesn't look completely like the one on the Basecamp diagram ) - I hope it is actually a 'c' as I've just ordered a load of parts It's a silent, multifuel burner, but it doesn't have a choke (I think called a 'slide valve' on the basecamp diagram of the 'c'?) and it's control valve is on the right of the burner (when facing the user). I'll try to get some picture sand se if anyone can confirm what I've actually got.... best Matt
I have two 111T's and one 111C. The C has the control valve on my left,(when facing it) it has a black/gray case and tank and the cobra burner is chunky and short. The pump leather is, well leather. The T's have the control valve my right (when facing it), have a brass tank and a tall graceful burner. The pump leathers were rubber o-rings untill I replaced them with leather. A few folks badmouth the C but to me these are equivelant stoves. Both work well when set up correctly. I like the simmering ability for cooking very much.
Thanks for the help guys - I think mine's a 't' (I googled and found this picture, which looks exactly my burner, except mine stove doesn't have any restrictor tubes, has a leather cup on the pump and has the chunky handwheel with no spanner). Happily it looks like all the parts I've just ordered from base Camp are common to the 't' and 'c', so should be fine with my stove. I tried it today with kerosene rather than white gas (actually 28 second heating oil, as it's all I have to hand!). It seemed marginally better, but on a low simmer, a slight draught (or gentle puff of breath) was enough to send it into underburn again. I'll give it a go with the new inner and outer domes when they arrive and see what happens. best Matt
If you got the black nob wrench for the adjustment the back side is for the jet and stuffing box no need for spanner. [oops front nipple wrench back stuffing box]
Matt, Don't worry about not having the restrictor tubes, unless you plan to run your stove on meths, and really, why would you ? sits back in chair and awaits the flaming attacks from those who use meths in their 111T's and C's. Hiya Doc
Well Spudz get off your chair i got one ruining alcohol silent burner, Now what have you to say to that.
Whats wrong with meths in a T Quick lighting. Good low simmering. Burns super clean. Bit slower on the boiling but who cares!!! Bloody heathens!!!....Better than chorinated hydrocarbons anyday!!!! Barra
I hate to rain on anyon's parade.. but if you use methanol in your stove... Yellow heet... It is derived from natural gas. Ethanol is derived from corn usually. (in the US) Brazil may become a world player on the ethanol front by growing massive amounts of sugarcane that can be converted to ethanol more cheaply.
But 'meths' isn't methanol, it's methylated ethanol : http://en.wikipedia.org/wiki/Methylated_spirit best Matt
Thanks for all the advice guys - I'll get this underburning thing cracked in the end! Or perhaps I need a roarer kero burner too ..... (In fact I definitely want a roarer kero burner, but I can't find one!) best Matt
methalated ethanol is what you buy as de-natured alcohol this is sold as shellac thinner and marine stove fuel. HEET in the yellow bottle is 99%+ Methanol only. No ethanol. Not Green. Made from fossil fuel. Period.
Perhaps we are suffering from a transatlantic difference in terminology here What spudz referred to earlier as 'meths' here in the UK is methylated ethanol (basically poisoned ethanol to prevent it being drunk). We can't buy methanol (or HEET) here in the UK - at least not in any significant qualtity (it is used in model aircraft fuel blends, but you buy tiny little cans at extortionate prices). Unfortunately we don't have the auto / tuning stores that you have in the states where you can buy methanol in reasonable quantities. So what spudz referred to as meths (I think) and certainly what I know as meths here in the UK (and what I was referring to in my earlier posts) is what you guys across the pond know as denatured alcohol or ethanol. We can't even buy proper undyed denatured alcohol without a special licence (I have such a licence, but they're hard to get hold of now as the rules have been tightened) - I envy you guys being able to go to a store and get this sort of thing over the counter! So, if I chose to burn meths in a stove here in the UK, I'd be burning an ethanol based fuel (not that I would as it's so damn expensive! - it's naptha or kero for me!) best Matt
What he said .. except for the expense of meths. I can buy a bottle of this ... for 0,99 Eurocents, about ?0,65 pennies. My original comment about 'Why would you burn meths in a 111T or C stove' had more to do with the flame, odour and heat output of kero. I like kero / paraffin, oh yes I do. Enjoy the Flame
Matt you have it. When I tried to figure out just what the composition of denatured alcohol consisted of I had to go to the MSDS (material safety data sheets) of the manufactures to find out for sure, they don't seem to want you to know, Most of ours contains 85% ethanol, 5% or more methanol, and the balance is other, 1% aliphatic hydrocarbons, the later having to do with a manufacturing process eliminating water from the product. It is mostly labeled Denatured Alcohol and Shellac Thinner, and sometimes added is Marine Stove Fuel. Price is about $10 a gallon here where I live, and it burns very clean with a pleasant odor. I keep hearing that it is hard to come by in the UK but don't understand why that should be, it is commonly used here as it is labeled. On Methanol, like the yellow bottles of Heet, I tried using that in a Glogau alcohol stove that I use denatured alcohol in normally, I found it didn't burn as well and left soot on the bottom of the pot that was used in the experiment. With the corrosive properties of methanol it is an over all bust from my view, and denatured alcohol is much cheaper for us in the USA. Ed
Ah, good! - I was on the right track Just to make all you guys over there thankful - I pay ?15 ukp ($30 ? ) a gallon for proper undyed, odourless denatured alcohol and about the same for panel wipe (naptha / coleman fuel substitute) - genuine coleman fuel is ridiculously expensive! Thankfully kero is reasonable - about ?3 / $6 a gallon. I must get me a roarer kero burner best Matt
