Optimus 8R, has no pressurizer, what could I use in lieu?

So I just found out this is the name of the stove my mum gave me which she said she used with the family as a child, circa 1950s.

We could not get it to light before, having no idea how it worked, but looking up a video I see the gentleman puts some gas into the little saucer below the wick as starter. We didnt do that however next he picks up an item which is not in our stove case which he then says is the pressurizer.

Can I easily DIY one of those? There is no hope of finding if we still have that and I imagine, as quite the collectors items from what I see online, a proper replacement might be hard to get and if not expensive. Also it seems it wouldnt be a difficult item to diy yourself with a little thought?

So any suggestions and/or is it essential for proper operation? Looking at some videos of coleman stoves which are pressurized this is the part that makes it turn into a gas it that right? So is it essential? I suppose it would be nice to also be able to make it a gas and to have full functionality.

 

Wow I am just watching a some videos and this baby doesnt look safe to run inside a van with both videos showing the flames burst out and light the surroundings before warming up.

Ok the guy in the second video says he must have spilled some fuel when filling so that would explain. Perhaps just be careful with filling and do that outdoors only.

 

Ok more research indicates the pressurizer is optional, and maybe did not even come with some models, in this case perhaps the one I have, and perhaps just for high altitudes?

Will give it a test shortly.

 

The 8R is self-pressurising. The man in the video uses the little pump (mini pump) marketed by Optimus and handy in very cold conditions. It has its own special filler cap. The normal starting procedure for 8R and similar self-pressurising small stoves is easy. Unscrew the filler cap to equalise pressure in the fount (there may be some vacuüm which will prevent starting up), close the valve, fill the primer cup preferably with alcohol (ethanol, methanol or a mix, not important) or clear petrol (will produce sooth) and light it. When almost burned, open the valve and your stove should now start burning without fire balls or other scary events.

Hope this helps.

 

You can get these started and running without the pump.

Open the valve at the burner, place your hands on the tank, and slowly the fuel will run into the bowl under the burner. When 1/2 full close the valve and light the fuel in the priming cup. Just before it burns out, open the valve 1/2 way.

Practice the valve movements before priming so you know which way is off and which way is cleaning. Cleaning pushes a wire up through the burner.

(Use aspen/panel wipe type stuff, NOT gasoline and NOT paraffin)

I see @Wim has beaten me to the punch. He is right that you can prime with alcohol instead.

 

Thanks both.

Why dont use gasoline? Here in the UK called petrol. It says on the sticker "for gasoline" so would sure think it would run on that? I specifically would be interested in using gas for most availability and I could just buy a bottle when I am filling up my diesel for my van?

Will it also run on meths (not just priming) or will it not be suitable due to pressure or lighting point or somesuch?

 

Unlike panel wipe/Aspen4/brake cleaner/Coleman fuel etc, car fuel contains a lot of nasty stuff that likes to block things, clog up, produce cancerogenic fumes and so on. So, it can be used in an emergency, but if you like your stove to be reliable and burn clean I'd advice to NOT use car petrol.

 

First things first, as this is somebody clearly new to self-pressrising petrol stoves- There are some safety issues here.

At the very least it would be best to check the filler cap seal first- the old one may well have hardened and not give an effective seal.

Petrol stoves are safe to use when in good working order, but can be dangerous if not and so need to be treated with care. Never open the fuel cap to turn the stove off as the vapour within is likely to cause a fireball.

I'd replace the seal before trying to run the stove as a matter of course, at the very least immerse the empty tank in hot water and see if any bubbles arise, indicating leaks, as the air inside warms up and pressurises.

The fumes even from burning naptha (a more 'pure' version of petrol in layman's terms) mean this is a stove to use outdoors, but they are a great practical bit of kit.

A search for '8r fuel' will give you recommendations for what to use in ther UK.

 

My mum said it must not have been run since about the 70s when she said she would have bought it for camping.

I had gone offline before seeing that. I dont know if it is related to anything you mention above but when I fired it up and fiddled with the nozzle a bit, after a bit of nozzle twiddling, there was a HUGE jet that came up maybe one foot in the direction that would have been my face if I hadnt been sitting well clear to the side, which I did as I saw how it had begun doing little jets before and so knelt clear.

I am not sure if that is maybe because I didnt have that four pronged cover over the top at the time? I put it on after and it didnt happen again however I dont know if that was correlation or causation.

After that it worked great and got a feel for it after having left it and come back to it later to actually cook something and it worked in a reliable fashion. It cooked rice really efficiently compared to the alcohol.

If this stove is not better indoors than the alcohol one, though, I am not in a much better position than before, other than it cooks a bit quicker but I have no shortage of time and using stinky petrol is not worth the extra hasstle vs the cleaner bioethanol. Even if I wanted to cook outdoors with it the petrol stank out my van leaving it in the foot well so I took it out and back in the garage. Seems it would have a place as a backup or novelty item only in this case. It certainly was cool to use it though and see that jet kind of action once it turns into gas.

The flame is much more controllable than the trangia so that is certainly a plus for it. Is there not a clean burning fuel, equivalent to bioethanol I could use with it for everyday use?

 

Please don't start your 8R inside a van. As you've seen in the video, they sometimes flare on starting. I would hesitate to even use a self-pressurizing gasoline stove inside a closed space.

If that's what you're going to do, please practice lighting and running the stove outside, until you're completely familiar with its operation. Then start the stove outside before moving it inside, and keep it well away from flammable stuff, like curtains and bedding.

Just reading your latest. That "four-pronged cover" is the burner plate and must be in place before you try starting the stove. So I will repeat what I just said,

"please practice lighting and running the stove outside, until you're completely familiar with its operation."

....Arch

 

The flame plate/spreader is essential. As you found.
It won’t burn alcohol. Naphtha/Coleman is a clean-burning fuel.
Causation. Obviously.

 

Indeed, as you saw from that post I found that out myself regarding the jet. Can that also happen with the plate spreader on?

I am certainly going to continue using it outside for the time being. No intentions to venture it inside yet if at all. I still would not try the trangia inside even though I used that for over a month almost daily. This one has a more controllable flame than trangia though, so there is that. Aside from the startup which produces some wily flames (which I guess can be minimized with experience and varying when you open the tank) the blue flame once warmed up seems similar, in terms of controlled flame, to a gas stove which are commonly used inside vans.

So it is the spreader that stops jetting? Ah see your edit, ok cool. Naphtha is a readily available source in the UK so no problem switching to that and doubt that will dry up any time soon, though who knows these days but for now seems a good option. I guess it is just cleaner than usual petrol and not clean per se? As in not as clean as bioethanol?

 

I am thinking maybe it is perhaps better to get comfortable cooking outside. My issue so far has been, in the uk, it is hard to find any privacy to cook without people coming past in cars, even in very rural places. I guess they dont give a hoot but I still feel exposed when cooking and you are a sitting duck for 1 hour or so while things cook and would clunkly to pack things away quickly if I wanted to.

I am not sure what I am afraid of there I just like to not feel like people are watching me since it is somewhat unusual to be cooking out of a van on the side of the road even with the boom in vanlife here. Even so I prefer not be seen as "one of those vanlifers" and like to stay well under the radar.

 

Find a place in a park and cook on a picnic table. Everyone will think you're just stopping for tea.

....Arch

 

It’s a camping/hiking stove, intended for outdoor use. The fuel is very volatile. Priming, spills, etc are mostly benign outside. Indoors, in a van or tent- not.
Outdoor operation, rightly done, is quite safe.

 

Sometimes the term "naptha" is used to describe kerosene. This stove is not designed to work with kerosene.

The right "naptha" to use is called Coleman fuel / panel wipe / Aspen in the UK. Here in Australia it is called Shellite. The below instructions call it white gasoline / petrol and say not to use pump petrol. It is what low octane gasoline / petrol used to mainly be made of before a whole lot of new additives turned it into modern petrol. Modern pump petrol is not a good choice if you want a reliable stove for the reasons already mentioned, which is down to all those additives (to increase octane, lubricate engine valves etc etc).

Bioethanol is not an available choice with this stove, AFAIK. The jet is the wrong size just to start with. There is no other fuel option for this stove.

 

It would still be wise to replace the filler cap seal, otherwise the stove is potentially an accident waiting to happen.

As mentioned on the other thread, the 8r is intended for camping use- short quick meals, a long session with a large pot and the tank may over-pressurise, causing the safety valve (abbreviated to SRV on this forum) to open, often with a small flame.

Fine if you're doing simple camping-type cooking, not a good choice for gourmet options! But these stoves are a well proven design, hundreds of thousands if not millions were made and sold.

HGV drivers stop in laybys and cook in their cabs as part of their jobs. Just pick somewhere safe from being hit by cars if anybody is eyeballing what you're up to rather than watching the road (target fixation!) Avoid urban council estates, and in the countryside, don't spread stuff all over the place and look like you're going to be there the night. You'll be fine, there's nothing to worry about.

I don't think people will be looking at you and considering you a 'vanlifer'. I think the words of choice will be much ruder and not repeatable here. But so what. I lived a semi-nomadic lifestyle in summer in the UK for a few years. You need to be thick skinned, and treat it as an adventure.

Covered in post #5&7, in the UK naptha is naptha!

 

Thanks! Good to know, even though these days I try not to venture away from ethanol myself… !

 

@Alcoholic in the UK, if used daily, it would be cheaper to forget living in a vehicle and rent a house!

 

About the same price as here? Methylated Spirits (5 Litres) 16 GBP for 5 litres? FYI ours is around 2.5 GBP per litre...