Petromax 829B is it original?

It's not leaking through the threads, it's leaking through the jet orifice while the needle is up once the carburetor is heated sufficiently.

 

Sounds like some debris and carbon sank down to the foot valve, preventing the pip from sealing properly. You can attempt a purge by removing the vaporizer and let the kerosene fountain with pressure, have a rag handy as you purge.

 

Regarding the leaking jet orifice: it's not detrimental to the function of the lantern is it? It only leaks once the carburetor has gotten hot enough to start to vaporize the fuel.

 

I was just testing the jet streams and I probably flooded the carburetor. If this is the case, is there nothing wrong with the jet?

 

Sometimes it happens, during the preheat the mantle starts to glow if any kerosene was trapped in the vaporizer. Or starts smelling bad. You typically don't store your lantern with the bleeder close. The foot valve is only really there to facilitate the function of the rapid to build pressure, the pressure in the fount provides the bulk of the sealing action. When not pressurized, sometime the valve slightly unseats and atmospheric pressure or off gassing of the kerosene causes the fuel to collect inside the vaporizer, sometimes leak from the tip and puddle all over the place.

 

Well that's good to know there's probably nothing wrong with my jet or needle.

All there is left to do now is wait for the Preston loop. Or put white gas into the lantern. I am pretty curious about doing it. What's the worst they could happen? Could the lantern explode?

 

Explode is probably putting it lightly.

 

I see, well thats no good. The Preston loop carburetor arrives on Friday.

 

The jet stream's good enough. As long as the angle of skew isn't that acute and the stream is 'thin', it should be ok.

 

Before you have a Preston loop in place, you can still test the existing if vaporization a real problem on the straight carburretor.
While it is fired up, use a small butane or propane torch to heat the vaporizer while it is in operation.
You can perform it with the glass globe removed.
If this alone can eliminate the flaming outside the mantle, then poor vaporization would be the main 'culprit' in this case.
If even the above doesn't get rid of the flaming outside the mantle, then poor vaporization alone isn't the real cause.

 

I'll try that today and get back to you.

 

I think it's the vaporizer. Using a torch to heat the B vaporizer caused a blinding white light and nearly eliminated all the halo. It was a windy when I tested it just now. Here are a couple pictures with different white balance.

 

Question, have you been doing all your test lights with the hood off? If so, put it back on, it helps the slow the escape of heat needed for your anemic B vaporizer. Also run the rapid torch for longer, like a minute and a half, maybe 2. Of course also have the globe on, too.

 

@Dashwood
I have done the things you suggested and still got the flaming mantle.

All test lights with hood on and long run time on the rapid. This is the first time I tested with the hood off because I was heating the vaporizer with a torch.

 

While you claim the insides of your vaporizer is "clean" I still suspect carbon deposits are still present as a glassed layer clinging to the walls giving it a "smooth" clean appearance that's hard to tell since you can't stick a light inside, besides the light coming in the opposite end, still very hard to see. If you're brave, I suggest removing the vaporizer and give a nice heating till it *barely* glows or sufficient time you're comfortable with and quench it water, this will break up the glassed layer that's preventing heat penetration as it acts as an insulator. Proceed to clean it out with a brass gun barrel brush and be amazed by the amount of carbon that spills out.

Also note the smoke billowing out the ends as the carbon heats and burns in the free atmosphere.

 

I did the heat and quench earlier, but I did not clean with a bronze barrel brush.

I let it sit in nearly boiling lye solution, then did a heat and quench.

With a flashlight shone through the vaporizer, I could see yellow brass. I think that this particular lantern would probably run fine on gas. It just doesn't like kerosene.

I don't think there's much more I can do except chance the vaporizer.

 

Looks like we've exhausted everything. Preston loop with the proper jet and needle is the way to go.

 

Great findings. So...it is inadequate vaporization indeed.
A Petromax 500cp should be 'blinding'...at all costs, whatever it takes.
It looks like you really need that Preston loop vaporizer.
Either that or use gasoline/ white gas .
There are safer alternatives which you still try with the straight vaporizer though...
My suggestions include:
- A 300/350cp jet.
- use a 500-600cp bulbous, Petromax-styled mantle. It'd bulge up and be in closer proximity to the vaporizer...probably might help to some extents.
- pack the vaporizer with some bronze wool or some other heat resistant fibrous material.
***the last one isn't intended for reducing pulsations this time
I would try that just to reduce the total volume of the fuel within the vaporizer so that less total heat is required for vaporization of the fuel. You'd need to preheat slightly longer for this.
The alternatives might or might not work but in my opinion, still worth trying out.

 

You've all benn a great help. Thanks for helping me figure this out. We have an educated hypothesis now about what's causing my lantern to flame and burn dimly.

On Friday we'll find out if we're right about it.

I was very impressed with the light output. It put my coleman 220s to shame.

 

@MYN

It does make me question how Coleman has done it on their kerosene lines, all of which minus the "Col-Max" use straight vaporizers that are even smaller, possibly the jetting?

 

@MYN

Thanks for the suggestions, but at this point I think I'm done messing with the B vaporizer. If I were to use it, I would try an Amish mix. But I understand it's unsafe, so I will simply wait for the Preston loop.

 

@Dashwood
The vaporizer / generator on those colemans have ribs on them. Maybe they help with heating?

 

@Gilbert

Odorless Mineral spirit is another alternative that's apparently easier to light with but just as safe and identical to kerosene but much cleaner, along with ultra refined synthesized kerosene called "Klean-Heat" from Kwik Strip.

Both are somewhat pricey but I choose to run them because way less carboning, longer generator life, and less odor during various combustion condition.

Also that generator is unique to one line of lanterns Coleman made, I'm talking about other ones like the 639 and 237, all use straight unribbed vaporizers, most of which contain two coil springs inside.

 

It basically means the straight vaporizer would still work on a Petromax with kero.
I'd not put on the Preston Loop yet on this. This is the best time to exhaust all solutions.
Once Preston loop is in, and the lantern works nicely, the 'heat' of discovery would actually go downhill.

 

The Coleman 237 and 249 do not need the vaporizer to be ribbed to work with kero...

 

@MYN

I like a good mystery!

 

@MYN I suspect the 249, 237, and 639 can burn kero due to how close the mantle is to the generator, they are sometimes almost touching depending on how you preburn and inflate them. And since they're skinnier, less heating is needed to vaporize the smaller volume of fuel.

 

I believe that is certainly contributive.

 

@Gilbert @MYN

All this talk makes me want to finish fettling my CJN Branded Amish modified "Workhorse" Petromax Lantern. Pump NRV needs replacing and I just need to buy special tools to remove it to change seals.

 

The Workhorse is certainly a nice one. It is Petromax style but has a shut off valve and an air intake tube. That should work with any kind of common liquid fuels..
Too bad it isn't as common.