Petromax mantles

@Peter Perry
The needle should show only 0.5mm above yet , when in upper position.
Else needle might block the orifice while in lower position..

 

@bp4willi thanks for that.
Comment noted ✅

 

@Mr cod
Hi Ian yes your right after all the frustration she's running very well.
Still problems with the control wheel locking one way so will have to be looked at again but for now just enjoying the moment .

 

That the wheel locks up when turned one way but not the other still mystifies me and I've run out of suggestions as to identify the cause.
That the lantern leaks fuel when it's turned off is a different matter.

Referring to the foot valve as shown in the second image in the fourth post here
a technical description on how to perform a complete cleaning and restoration of a PETROMAX 829 500 - Pelam.de Forum it's important that everything is spotlessly clean as even the smallest speck of dirt can cause the valve to fail which allows fuel to flow up the vapouriser and leak out of the jet. Check that the individual componants are clean. Does the spring-loaded pip slide easily in the valve casing ? Polish with 0000 grade wire wool if necessary. Stretch the spring a little. Unlikely as it may be, it is possible that the rod is out of adjustment and should be checked as suggested by @WimVe. With the foot valve assembled and screwed onto the lower vapouriser, insert the rod assembly. The spring in the valve should support the rod so that the slot in the receiver is no higher than shown in the image in post 6.

When re-assembling, don't bother with a new lead washer, put a couple of turns of PTFE tape on the threads. Use the stuff on a yellow reel, it's thicker.

 

@Henry Plews thanks Henry that link you sent was the one I used to understand how it all works so very useful.
The only thing I haven't spent much time on is the foot valve I just replaced the nrv so I'll take another look at the spring etc.
As for the locking up I'm totally baffled by it I had it working then yesterday it didn't, I've cleaned it with 00 wire wool in case a burr or something was catching it and even had it on the buffing wheel so it's as clean as it's ever going to be .
I may be tempted to replace the rod from base camp for a tenner at least that should eliminate one part of the mystery or am I clutching at straws .

 

Well it would not (or better should not)
The extender block will always stay on the same axle height of the main hand wheel. It will move up/down when operated but that is how it works. Adjusting the length of the needle rod will not effect the valve rod nor the position of the extender block.

But leave it for now since the lantern light well as we can see.

 

Yes it does light up nicely now but I'm pretty sure you'd still want to sort out that 'nuisance' catch on the pricker control.
Since you've already arrived at this stage of fettle, I'd reckon it won't be too difficult to dis-assemble the generator/pricker control/footvalve. Only need to be gentle to avoid using brute-force and damaging anything.
Remove the upper generator/Preston loop first and turn the pricker control wheel. Test if it still catches.
If it does, then then remove the entire lower generator-fuel pick up assembly and check through everything inside, including the footvalve.
Check that the eccentric block has been assembled exactly like that shown in Henry's photo and not upside down:-

I've seen at least one that had been wrongly assembled(upside down) and the result was that the pricker wheel can't be turned 360° in any direction.
On other instances, I found that the lower pricker rod was bent and there were some carbonized material and other stuffs partially restricting the rod's movement.
Whatever it is, you'd need to dis-assemble the lower generator to find out. At the same time, you'd get first hand experience on the footvalve as well.

 

I found (incidentally my first ever fettle which was on an Optimus 350) that if either rod is set too long it cannot go past the apogee of travel. Sounds like Peter has the top rod set correctly as the needle protrusion is more or less correct. I suspect the bottom rod can't get past the greatest compression of the foor valve seal and spring.
My other thought/experience was mis-locating the excentre "pip" that acts on the rods. I managed to do both of these back then and chased my tail a little.

Great to see it working Peter !

 

@WimVe with a full tank of fuel and a new mantle I have no intention of rocking the apple cart at the moment so your absolutely right on that score but this locking business is still a puzzle that needs solving at some point and lower the needle at the same time .

 

@Fireexit1 thanks for that and yes it's great to see the lamp burst into light rather than flames.
But sooner or later it will be yet another strip down over the locking up I'm experiencing and can't at this point think of a solution to it except perhaps replacing parts but that's something to think about later.

 

@Peter Perry , well full tank or not, you can remove the upper parts with the mantle intact when being carefull. The full tank only last for about 8 hours....
Remove then the vaporiser upper part, check like said, if the rod is hold by the extender block, rotate the hand wheel, is it blocking then you have an issue with the length of the lower part, if not then move the nut (of the upper rod part) 1mm up the rod and fasten the rod with the nut. When done with care nothing will bend or have effects on the lower main foot valve.

You have replaced the main valve but , I think, not checked if it blocks the hand wheel rotation.
The same goes for the needle/jet replacement.

 

@WimVe yes well I could do that but not at the moment I'm enjoying it too much the leak is not massive so not really cause for concern though I will take your advice and sort it .
The locking of the wheel is more of a concern to me in that it doesn't do what it's supposed to do .
Why does it turn 360 one way but not the other and the new nrv valve has no bearing on it as I had the same problem before I replaced it should I just replace the whole thing and damn the expense?

 

@WimVe sorry ignore last post I misunderstood what you said .

 

@MYN hi I do apologise I forgot to reply to your very important information and yes it will have to be stripped once again but to be honest I'm at a loss everything looks like your pics everything is clean no burrs nothing.
I could head straight to the foot valve but again I have replaced the nrv valve and no change to the locking up as it used to happen before I replaced it so I plan to strip it yet again I just wish something jumped out at me so I could pinpoint the problem.
Thanks for your contribution.

 

I must be doing something right guys four hour burn and not missed a beat.

Good Times

 

As long as the tank has pressure it will run for about 8 hours.
If you even don't have to "needle', use the cleaning needle, you have done a good job.

 

Congratulations Peter for sticking with it. You have a good looking lantern that's running nice and bright.
Yes, there is still a slight problem and I'm sure in time you can solve that too.
Personally I don't rely on foot valves to seal when the lantern is not in use. I release the pressure and leave the cap loose.

 

@ROBBO55 hello thank you and yes she's running really well now and your right about not relying on the foot valve I don't either especially with a locking wheel.
Not sure if a petromax is the ideal lamp to cut your teeth on for a novice like myself but as it was in a skip I guess I was thrown into the deep end .
Many thanks

 

@WimVe hello thanks very much your knowledge has been invaluable to get it running. She ran till I released the pressure about four and a half hours with an occasional pump and check of pressure not needed the needle so well happy

 

Now you have a good understanding of the Petromax "system" you now understand many other brands as they are invariably variations on the same design. Also you took a pice of junk and turned it into a working lantern . You probably now understand what drives many of the happy throng on this forum

 

If you decide to strip it down again, I'd suggest you remove the whole vaporizer assembly from the fount and then examine it further.
Re-assemble just the vaporizer and needle controls separately outside so that it looks like this:

Turn the pricker knob repeatedly to test the cleaning mechanism and see that the needle protrudes and retracts from the jet orifice. It should function just the same way, be it assembled on the fount or alone/independently.
If its stuck or anything, you'd be prompted to strip that down further till you see exactly why it is so. The whole thing isn't rocket science and can often be self-explanatory once you're at it. Good luck.

 

@MYN hi thanks for that it's exactly what I'll do when I strip it down yet again

 

@Fireexit1 funny you should say that I've become quite attached to it after a very frustrating start .
A bit of patience works wonders

 

I wouldn't be surprised if your collection of one started to multiply! There's plenty of Tilley 246's out there that need some TLC and everyone needs at least one Coleman.... oh and a Bialaddin of course!

Glad it's working. As for the pricker knob rotation problem, I'm very sure you'll get that sorted soon enough!

 

@ColinG hi well I do have my eye on a nice little lamp I may take the plunge .
And yes the control valve will have to be looked at again ,it works really well at the moment but obviously it doesn't work as it should so annoying.
Thanks for getting in touch.

 

Just a question, but when you take the generator/vaporiser/Preston loop off, does the control wheel turn easy both ways or not? You probably already covered this in the post but it might eliminate/highlight where the problem is.

So what's this new lantern you've got your eyes on?

 

@ColinG that's a good question and it's reminded me that with the loop off the centre rod jolts and moves slightly so turning anti clockwise the centre rod lowers smoothly till the wheel reaches twenty past if it were a clock then a jolt slight twist of the needle rod then continues smoothly up to twelve o clock with the needle raised.
Turning clockwise needle disappears till twenty past then lock.
So it feels like the jolt and movement of the needle rod throws it out of sync.
I'm beginning to think its the eccentric nipple which may be causing the problems any thoughts Colin.

 

@ColinG sorry Colin forgot to answer your second question the new lamp is a bialaddin 300x should be here this week I'll post a pic

 

Nice! It'll be interesting to know what you think of a Bialaddin compared to the Petromax as they're very different.

 

It sounds like either the eccentric protrusion on the end of the control rod or the eccentric block (with the channel) has sustained some wear over time or maybe one or both have developed a burr. Or... if someone in the past has used a different pricker rod which screws down too far into the eccentric block. I noticed that the threaded hole (where the pricker rod attaches) goes right through so it could make the mechanism catch.

Honestly, repairing lanterns is like being an archeologist sometimes! It can be very rewarding but also bl00dy frustrating!