Hipólito H 202 needle breakage

Sorry mixed up some topics.

 

All cleaned up for your viewing pleasure



I know these things always look quite roughly finished, but what do you think of the area just to the right of where the upper part of the loop attaches to the main tube?

P.S. I don’t personally think the problem has to do with the fastening tension of the jet since I see no evidence of leakage at the point where the base of the jet is seated on the mating surface of the vapouriser.

 

Use an open-end wrench to carefully tighten the jet inside the mixing chamber while the lamp is in operation.

 

If that was a crack where the upper end of the Preston loop attaches to the stem then it matches quite well with the soot blackened area in your previous photo.

I think I would fire it up again, wait and look for any yellow flame occurring in that area. The source should be plain to see.

 

I’ll consider trying that but I do worry a bit about safety. If this would have to be done without the vent in place and it wouldn’t be possible to hold the Preston loop for support/leverage, I wonder how effectively I could even tighten the jet (which is already very tight). It seems like I would just be twisting the whole vapouriser assembly. As a reminder, I’ve used two previously unused original equipment jets and had the same problem, so I really don’t think this has anything to do with the jet not being tight enough.

Would it not be prudent to plug the top end of the vap tube, fill it with soapy water, introduce some compressed air and check for bubbles? The only shortcoming I see is if the crack (if there is one) only opens up under conditions of extreme heat. I think someone mentioned that earlier.

I’m also curious how the picture someone shared earlier shows flames on the upper vapouriser with no inner case installed. How can that be, unless something like gasoline is being used? I must be failing to grasp something simple (again) here.

 

Yes that was my picture and it was running paraffin. I did it because it would flare up instead of running normally and it wouldn't go out as it should when turned off.

I took the hood off after blocking the jet with the needle and it continued to burn. Problem was obvious.

 

Thanks, mate. That’s exactly what I’m going to do. Simple, safe(r), and should yield the needed information about whether I should silver solder any part of the vapouriser or just buy a new one if it’s cheaper than messing with it. Plus it won’t dirty the inner casing I spent an hour cleaning last night.

 

I do hope that is not a crack for your sake but it would explain the observations. It would need to be hot to open up and show the problem. Don't get burnt! I used pliers.

 

How did you secure the scorching hot vapouriser when wrenching on the jet? Sorry for the continued questions, I just want to know how you tackled this. What were the pliers for? I would have thought of using a long-handled spanner.

 

No I only used the pliers to take the hood and mantle assembly off. Martin K mentioned upthread about tightening the nipple while running. I have never attempted that.
I waited for it all to cool down first and then gave it some with a ring spanner while holding the preston loop in the opposite hand.

 

@Jaska

there are specialist sprays available for detecting cracks in metal?
You would have to do an online search to find availability and also how to use properly.. it may also not be cost effective but it is an option

 

It does look like the crack detection methods would cost a lot more than simply buying a new upper vapouriser. Unfortunately Petromax charges outrageous shipping fees. I recently bought literally a few grams’ worth of parts from them and they charged me 17€ shipping.

 

> cost a lot more than simply buying a new upper vapouriser.
The H202 ist a 250 cp Lamp. This vapourisers are not more on stock as a new Petromax spare part and also not so easy to find in good used condition.

 

@Jaska
If you have another similarly rated Hipolito or Petromax, you can try using this vaporizer on another lantern. To see if it produces the same issues.

 

I experienced on a similar 'hardly noticeable' leak on an Aida lantern.
The crack only showed its effects when running/heated up.
My solution then was to silbraze it.

 

I don’t have another 250 CP Petromax-style lantern, unfortunately.

If silbrazing, done correctly, would be non-destructive, I could try that at some point. It’s really a shame about this. The lantern is currently repackaged in its box and may never see the light of day again, depending upon whether I have the time, inclination and resources to learn the art of silbrazing. If I knew a local hobbyist who wanted such a lantern I’d probably sell it.

 

You can't be certain that it was really the vaporizer that was leaking until you could verify it by observing a small yellow flame emanating from any part of it, be it during operation, starting or shutting down the lantern.
Have you tried getting a better view by operating the lantern without the outer hood attached? If the leak is just from the threaded joint between the vaporizer and jet, the solution might be a lot easier.
Sometimes, the fuel-air vapour do get ignited and starts to burn with yellow sooty flames around the jet/air gap area due to low fuel flow velocities or skewed flow paths during shut downs. More likely to happen if there is a large gap between the upper vaporizer and the inner hood's hole where the vaporizer or jet protrudes through. It can also happen if the flame from the mantle back-burns through a short j-tube mixing chamber when fuel-air flow is greatly reduced during shutdowns or when fount pressures become too low.
It might take some amounts of further observations to ascertain the real cause of the issue.
Silver soldering is only necessary if you have ascertained that the vaporizer is leaky.

 

Basic question first is: do you want to get the lantern up and running or not?
Since again you point to selling it.

Like @MYN writes, first find the problem before stating the fact that you can silbraze.

Another possibility may be that the fuel/air spray doesn't go straight up into the J-tube.
A thing you may or must always check on lanterns.

 

I’ve gotten the lantern set up again, installed a new mantle, and it’s been running without the outer hood for about 70 minutes now. I’ve kept the pressure just above the red line. At one point I raised and lowered the needle to smooth out the operation but other than that there’s been nothing spectacular.

When it comes to all the advice given so far, I’m very thankful for it. Some folks seem to be hypercritical or judgmental in a way that I don’t like, so I’ll just skip past certain remarks or questions and focus on the more helpful (or at least kinder) ones.

I pretty much expect the symptoms to flare up at any moment, so I’ll try to keep an eye on things and see if there’s anything that points to the cause of the problem. As of now everything looks OK.

FIVE MINUTES LATER…

WOW!! Just as I was about to post this, the flames started shooting out of the lantern! I’ve got it on video. The pressure was still just above the red line but I noticed a sort of quiet before the storm. The light dimmed ever so slightly and the hiss quieted down just enough to notice it. I managed to get it under control by spinning the handwheel one revolution and now it seems to be running normally again.

 

The lantern is still running and there have been another couple of flare-ups. The vapouriser, to my eyes, looks perfectly clean and I have seen no flames coming out of any part of it. The whole area around where the jet sits on the vapouriser looks good, too. As far as I can tell, the flames all come straight through the burner and mantle.

 

My guess: Dirty fuel. I emptied the tank before putting the lantern in storage the other day and I can see some dirty greyish-black sediment at the bottom of the clear plastic fuel storage container, which was completely clean before I put the fuel in it. I’m going to shut off the lantern, let it cool down, remove the inner casing and glass, and empty the tank. I’ll then add some fresh fuel and shake it vigorously, drain it, and repeat until I’m sure it’s totally clean in there.

Maybe there was some kind of strange residue in the tank from all the years of storage . I’ll check this out and post an update after retesting with a clean tank and fresh fuel.

 

At a flare up: Then you should use the needle after all it is a cleaning needle.

 

From the descriptions in your last posts, it seems quite likely that you don't have a leak on any part of the vaporizer.
Partial blockage of the jet orifice by the occasional dirt, gunk or carbon particle is likely. This had certainly caused troubles on my lanterns in the past.
Do take note that it may not be that easy to clean out everything. It can be in the fuel, the fount or inside both the upper and lower parts of the vaporizer. Preston loop vaporizers are among the hardest to clean out completely.
The cleaning needle is certainly crucial for long term usage.

 

Thanks as usual , MYN. That aligns with my current thoughts and concerns about the lantern. After cleaning out the tank by swishing it thoroughly with fresh fuel and refilling it, I let it burn for over an hour and a half, during which time it probably worked better than it ever has. Around 45 minutes in, it briefly flared up and immediately cleared and recovered with a quick spin of the handwheel.

I had been wondering if I’ll need to contend with this for a long time as bits of impurities continue to work their way through the fuel system or if I should rather do a full disassembly and try to manually clean it out. What do you think? The debris in the tank/fuel looked like some sort of fine graphite powder or similar.

 

Yes, I believe you need to thoroughly perform a full disassembly and total clean out of all working parts.
The fount should be completely free from loose debris. They could be more than just a mixture of dirt, rust and old dried up or varnished fuel. The black powdery or graphite-like stuff could also originate from whatever carbon build-up inside the vaporizer. Some can loosen up from use and other disturbances. If it is possible, do a complete clean out on the inside of the vaporizer. Most of us here have done it. Often, we were surprised by the amount of carbon within the old vaporizers. A clean vaporizer can make a huge difference on the lantern's operating characteristics. It is just part of this collecting hobby.
If you decide to do this, you'd need to be extra careful in the process, bearing in mind that you do not have a spare vaporizer at hand. The same applies on other unseen parts as well. You might also want to scout around for some of the parts you do not have before embarking on this.
I'm sure members here are eveready to provide great advice along the way.

 

I don’t mind doing this. When you say “a complete clean out on the inside of the vaporizer,” is this any different than letting the parts soak in a mild citric acid bath for a few hours and rinsing/flushing them thoroughly? Does it do any good to shoot compressed air through them afterwards, or does contamination still remain in the Preston loop?

I had ordered a complete set of seals and spares for this lantern but unfortunately now most of them have been installed on my Optimus 350. Is there a better source in Europe for these spares than the Petromax website? They charge 17€ to ship seals, so I won’t be giving them my business in the future.

 

Any larger part of dirt / sediment from the tank which is able to block the jet may also be able to break / bend the needle. This needle can only remove smaller parts of carbon that built up in the vaporizer.

 

Yes, for that reason I won’t use the lantern anymore until I’ve properly stripped, cleaned, and reassembled it with any needed new seals.

 

It really depends on the condition inside the Preston loop vaporizer. Sometimes, I do a heat(dull red hot) and then quench in cool water to check if any hard coke/carbon detaches from the insides. Usually, I do find considerable amounts of a mixture of black 'chips and chunks', grainy as well as powdery deposits out of this coming out the vaporizer after a few cycles of the heat-quench.
Often, merely soaking in citric acid or most other solutions might not sufficiently clear up those well-used vaporizers.
However, I'd be wary should the vaporizer shows signs of being physically compromised. There is always a risk. Those heat-quench routines are pretty harsh and can cause any weak brazed joints on the Preston loop to give way and thus cause an otherwise non-leaky vaporizer to leak.
Nevertheless, it is one of most effective ways to clear out hard carbonized deposits in Preston loop vaporizers. There are also safer means used by many others, such as using a steel frayed-end brake cable attached to a rotating tool, i.e.,drill, Dremmel, etc. for cleaning out the internals.
Of all the clean-out means, from my own practices and experience, is to burn-out all the carbon within the Preston loop. This is rather more complicated and involves heating the vaporizer to dull red and then injecting pure oxygen into one end of the vaporizer. The other end(jet side) is kept open while the central contricted part between the two ends of the loop is blocked with heat-material. This allows oxygen to flow through the loop without getting short-circuited to the exit end.
When doing this, one needs to take extra care not cause the vaporizer to melt when the carbon is burning in pure oxygen within. He should withdraw both oxygen and heat source if he notices that the vaporizer starts to glow 'too brightly'(indicating overheating from the burning carbon).

 

That’s really good information there, MYN. While I could definitely try cleaning and service the vapouriser manually using some of those methods, I think it might end up doing more harm than good to a virtually unused part. Because the replacement part is no longer available, I’d just rather not take any unnecessary risk.

I’ve cautiously gone back on my word to not use the lamp anymore until stripping, cleaning and reassembling it with new seals. After thoroughly cleaning out the tank, I’ve run it for many hours to see if the symptoms would eventually clear up. It’s been working very, very well. It’s been easy enough to clear up any issues by raising and lowering the needle when necessary. I haven’t even had to do anything for the most part except regulate the operating pressure.

I don’t want to sound unreasonably or blindly optimistic at this point, but I feel like the issue may well have been properly identified and resolved. The Hipólito H-202 is a great little lantern and I’m happy I was able to find this one after the model was specifically recommended to me by someone on this forum.