Coleman 226 backpacking (?) lantern

I included the query (?) in the title against the lantern’s backpacking credentials because of the likelihood of mantle breakage in any mantle lamp jostled in a backpack.

For the jaunt in the header photo I’d gone prepared in anticipation of having to replace a mantle …




… at least once.




That aspect of the 226 covered, more on its characteristics after an extended period of owning it (much of the time relegating it to the shed) including this marathon analysis: Coleman 226 fuelling.

So, my conclusions.

It’s obviously small and lightweight and puts out a lot of light for its size. Good.

What’s not been good: I didn’t own my example from new, but it was little used and I’ve no reason to suppose that its lighting and running characteristics were worse than those of one fresh out of the box. It was from the outset temperamental to light until I realised (on stripping the lamp) that fuel pickup is through a tiny pinhole, little more than the size of the generator jet orifice. There is no fuel metering rod operating in a much larger fuel inlet orifice (as with a conventional Coleman) in the 226 design and it takes much longer - tank pressurised and control valve opened - for atomised fuel to reach the mantle enabling ignition than a Coleman like the 222 does.

Here’s the fuel pickup tip and the pinhole.




Apart from the extended lighting phase, that pinhole is prone to at least partial blockage and without a metering rod to poke the debris out it’s likely to remain obstructed. That explains the experience I’ve had with the 226, that it became difficult to light, and its banishment to storage began.

It would have remained there had it not been for an enquiry from @M4v3r1ck and contributions from @Dashwood in that thread on 226 fuelling. Their interest prompted me to retrieve the 226 and have another look.

Apart from the trouble I was having lighting the thing, in common with other owners of a 226 I found that it required frequent repressurising of the fuel tank in use, every ten minutes or so. The 222 I have stays pressurised for much longer, until it runs out of fuel typically. With both the 222 and the 226, their small size results in some self-pressurising of the fuel as the tank warms up but not significantly reducing the need for frequent pumping in the case of the 226.

The cause is the fuel/air pickup’s operating principle, relying on an atomiser (aerosol) action at the base of the pickup to produce a mixture of air and atomised fuel droplets to burn in the generator.

This device in essence …




… constructed as here in the 226.




The pinhole inlet for fuel ensures there’s no flooding of the aerosol action. When the fuel content of the mixture is vapourising in a hot generator the pressurised air drawn from above the fuel in the tank should reduce as external air mixed with vapourised fuel takes over after start-up. In practice, if the fluid dynamics and thermodynamic theory suggests that should be so it doesn’t work out that way and the tank depressurises as the air in the top of the tank continues to be injected into the generator to burn with the fuel.

View of the concentric tubes, ‘pinhole’ inlet component removed.




I decided to dispense with the atomiser configuration altogether and began by soldering a sleeve over the air inlet hole in the outer concentric tube. The O-ring pickup-to-valve seal wasn’t perished or torn but snapped on removing it for the soldering and was replaced. The end cap with the fuel inlet pinhole was dispensed with.




Next, I made a spirit pre-heat cup.








A side benefit of a spirit pre-heat is that kerosene can be burned successfully, as here.








The pleasing outcome was a 226 that remained lit without any pumping after the initial tank pressurising until the fuel ran out an hour later.

John

 

Well fettled!

 

Nicely done John

 

You always make great improvements.
It's educational.

I only have a 229, but will it be possible to use kerosene if the 229 is also equipped with a preheating cup?
I'm afraid that if I continue to use kerosene, the lighting will malfunction, so I've never tried it because I'm too timid.

If you have experience with lighting with kerosene, I would be happy if you could tell me your thoughts on the practicality of using kerosene.

 

@Camp numao
I don’t expect kerosene to lead to problems with the 226, but I speculate some might worry that the O-ring seals it relies on for the control spindle and eccentric block on/off function might degrade with the fuel.

I very much doubt that, since the pump gasoline the lamp is specified to use must surely have constituents with more potential to degrade the O-rings than kerosene. More reassuringly still, the patent quoted on the lamp’s collar, US Patent No. 4186760, suggests that the design lends itself to fuelling by kerosene. It says,

The patent does there speak of the fuelling difference between kerosene and gasoline and on using kero in the lamp I wondered if it might show signs of running fuel-rich, requiring a smaller jet to bring the fuel/air ratio back to an optimum figure for kero. I needn’t have worried, there’s no sign of that in use. I suspect that the tiny jet orifice in these lanterns of 0.006-inch (0.15mm) is so small as to make the fuel/air ratio difference of a small reduction far less critical than in a stove with a 0.32mm jet of five times the jet orifice area of the 226 jet. According to the attached table of Coleman jet sizes your 229 has the same size of jet as the 226.

All that said, you’d need to install a pre-heater spirit cup and I’d recommend blanking off the air inlet hole in the outer concentric tube of the fuel pickup as well as removing the tip cap ‘pinhole’ component, or widening the hole.

 

@presscall

Thank you.
I'm particularly ignorant about Coleman's structure, so could you please explain a bit more?

>I’d recommend blanking off the air inlet hole in the outer concentric tube of the fuel pickup as well as removing the tip cap ‘pinhole’ component, or widening the hole.

What would happen if you continued to use kerosene without doing this and only preheating it with the preheating cup?

 

@presscall

I will read your explanation again.

 

@presscall

I apologize for posting multiple comments in succession.

I have read everyone's test results.
I understand the following. Is this correct?

- If there are any parts in the small hole in the fuel intake, it will easily become clogged, so remove it.

- The air intake at the top of the tube inside the tank is used to act as a preheating burner. It will increase the speed at which the tank depressurizes, so it should be blocked. (This hole is not necessary as the tank will be preheated using the preheating cup.)

 

@Camp numao
Yes, you’ve understood. The primary failing with the 226 design is that the tank loses pressure far too quickly and that was what prompted my modifications. The ability to burn kerosene is a by-product, no big deal in itself, though in the UK at least Coleman fuel or Aspen is a lot more expensive than kerosene.

If you are adding a spirit cup to your lantern, be aware that the space between the nearest air tube/burner strut is restricted.




I found it useful to make the spirit cup a gentle push-fit into position so that if the lantern were on its side in transit (upside-down even!) the spirit cup will not slide up the generator and destroy the mantle. In the larger Coleman lanterns contemporary to the 226 there’s a clip on the upright to prevent the heat shield plate from flipping up and destroying the mantle. One’s absent on the 226, so the tight-fit spirit cup resolves that oversight also.

 

Hello all! nice job Presscall. I read all your work through the years.... how ever this coleman dip tub is a safety feature. In U.S. we are in constant state of being injured ,(so they claim). Then finding a lawyer too sue for damages. ( most likely from human error or stupidity ). The device "dip tube" utilizes pressure differential between inside tube and outer tube. this deference in pressure is measured in inches of water column. in an event the font is over pressurized or the generator to crack , (catastrophic failure) ,all air pressure will be exhausted first. The main purpose is simply too prevent over pressure to font.

 

@presscall

Thank you for letting me know.
So that's the kind of consideration that went into the preheating cup as well.

I'll try making one and lighting it with kerosene.
Thank you.



@pressnel

I see, so it acts as insurance in case something dangerous happens.
Everyone knows so much, it's amazing.

 

I’ve not heard that proposition before and it’s not stated in the patent for the lantern. I’m more inclined to see the too-rapid depressurisation as unintentional, a consequence of a design concept that didn’t work as intended.

Over-pressurisation of the fuel tank isn’t possible on the hand pump or unless it’s externally strongly heated (as in a fire) and a split or burst generator would still result in a fire regardless of the speed of depressurisation offered by the fuel pickup configuration, surely?

 

Over-pressurization refers to its set maximum operational pressure point. not the safe operation of sed maximum for pressure vessel. As for statement's made by patent ,their are numerus examples' of information intentionally left out of patents for many reasons too many to give in a short and over simplified answer. Let us instead focus on the principles of physics imposed on the object. the 288A was my first "instructor" on the principles of balance in a coleman product. note the orifice at bottom and at side of upper ,and the generators orifice. the significant is in the proportions given against one another including the inner and outer tube. all are part of the delicate balance. too change orifice size and or pressure in any location will resalt in change in resalts. just as a gas and a liquid interact.