Optimus 45 Burner Connector on the Loose

Need some advice here before I damage this beautiful Optimus 45 stove. I have a burner, whose riser tube is snugged down on to the fuel tank connector, which is loose. As I attempt to loosen the riser tube, the connector turns freely with the riser tube. I have a clamp that will attach to the connector, but I don't want to gouge or scratch the connector or riser tube in my attempts to fettle this.

Any thoughts? Should I re-solder it to the tank while it is on? Or is this indicative of worse symptoms?


sam

Here's a photo:

 

I reckon the solder between the riser tube and the tanks has cracked. You cannot see that solder as it is inside the tank.

There is a little way that sometimes works well. Turn the tank upside down, and heat the connection by a blow torch. This will melt the inner solder. During this process do not shake the tanksince for a good soldering, melted solder should get cold slowly and naturally.

Dear Mate, I would suggest you this way, as you would lose nothing by this method.

 

Hi Sam the male fitting on discus-style stove is attached to the top of the tank, from underneath, before the base of the tank is rolled and soldered into the top part of the tank.

I believe that male fitting itself is rolled sealed, or bolted, to the tank top and then soldered to seal.

It is not possible to re-tighten the fitting to the tank top as you do not have access to the nut.

As Sefa suggests, you can try cleaning carefully, fluxing well, and then re-soldering the joint, and it will likely work.

Plan B, if soldering is not successful, would be to remove as much solder as possible by heating, and then re-make the joint using a "silver solder" braze:

https://classiccampstoves.com/threads/7584

Best Regards,
Kerophile.

 

I was afraid of that. Hmmmm. I'll see what I can do about a soldering job.

I'll keep you posted on further developments.

Thanks,
sam

 

I pulled the pump tube off to see what I was in for. It looks like there is no retainer or nut that holds the connector to the tank. It looks like it is simply soldered on. Should be a snap to put back together.







One thing I noticed is that the pick-up tube is well off the bottom what looks like about 25mm. Seems like a lot of fuel not being picked up by the stove. I noticed this same thing in my Primus 100. I suppose it's that high up so that no dirt or other debris is picked up but that seems a pretty far up. Was there any other purpose than this?





sam

 

Hey Sam,

In the past I had a similar problem and renewed the solder by a laparoscopic job from the pump hole. It run very well.

I didn't think you would take the pump tube off. You can do it easily. If you do so, don't forget to share how it went.

 

I have done this by fluxing with a paint brush then getting a coil of solder around the pick up tube, then heating the outside of the up turned tank. You can look in the tube hole and see the solder melt.

 

Normally that part is soldered (from the inside) before the base of the tank is attached although I have seen 45's that have been resoldered from the collar as it would be difficult to resolder from the underside.

Ron

 

Made a little more progress on the stove. I couldn't get the solder to melt on the inside from heating the outside. I'm betting that the burner and riser tube was acting like a large heat sink preventing the work. So, instead of that, I silbrazed the connector right to the tank on the outside. As you can see in the picture, the gap that was there in the first picture above is no longer there and filled with silver solder - a lot of it. I've got a little bit of cleaning to do, but once the connector was soldered on, I was able to remove the burner and riser tube from the stubborn connection. Finally!

As you know, I removed the pump tube to get at the connector from inside the stove. Well, that didn't work so I ended up working on the pump tube and NRV. It wouldn't budge a bit, so I heated the end cap and pulled it off the end of the pump tube to get at the NRV better. I put the end cap in a clamp and was able to remove the NRV, which, of course, did not have the lead washer. As I was removing the NRV from the end cap, it squeaked and squealed as I turned it, even with oil all over it.




I would have liked to show you the whole stove in one piece. Haven't got it done and I'm a little tired. So, for now, you get to see it in pieces...

Will it ever work again?





Stay tuned...

sam

 

I reckon that's sensible, Sam, and a neat job you made of it. Lead solder would have made a seal, no doubt, but it's good to have the extra mechanical strength of the silver solder given the strain put on that component.

John

 

Hi Sam. Good job so far and well done, you have persistence, I'll say that for you! Will it ever work again?....well of course it will!

 

Sam the distance between the bottom of the riser tube and the bottom of the tank is far greater than normal. This is indicitive of an over-pressureized fount. It will work as you have it but as you might guess a lot of fuel will go unburned. It can be repaired but i've never done this. It would involve pressing the tank top down until the riser tube makes contact then heating the stove and allowing it to cool again very slowly. This "resets" the metal in a more normal posture. The problem; you will need a form which is shaped like the tank is suppose to be formed and then a method of heating the whole to a reset temp and allowning it to cool again. My suggestion for now, live with it.

BTW: GREAT FETTLE. WELL DONE lad.

lance

 

Pretty nice Sam, great job too.

 

The very first fire up of the stove. We'll see how good of a fix it got.



Priming.



Getting some green flames.



Established flame. We have lift off.



Flame is doing well. Red flame ring is a good sign.



Under the riser tube below the connector is where the fix was made. No leaks.



A better shot of the area in question



Flames.



Flames again.



Flames yet again.




Weird black kettle.



Kettle flames.



More kettle flames.



Even more kettle flames.



Steam.



Simmer flames.



sam

 

Looks pretty perfect to me, wished all my roarers burned so nice!

Regards,

Wim

 

Lift off 'ell, lad that stove is headed for Mars.

WELL DONE on a great fettle. And i'm in agreement i wish all my kero burners had such a loverly flame.

Blue flame, cherry red, it's a beautifull thing.

lance

 

Great job! Another 45 back in service.

 

That sucker looks like you have a turbo on it Sam.

 

Thanks for all the nice comments guys.

I wanted to put down what I did to this stove so you and I have notes on this. I'm starting to lose track of what I've done to some of my stoves and would like to remember.

First, the stove had a problem with the riser tube connector on the tank, that I silbrazed on. John (presscall), I decided to silbraze it on because I wasn't able to remove the fuel tube anyway and probably would never split the tank to get at it and was a little worried about softer solders melting away, apparently, like it did before. So, I made it a whole lot more permanent. It won't be melting off even if the whole stove caught on fire and exploded. Everything else might come apart, but that joint won't.

The NRV was stuck. No matter what I could not remove it. I removed the pump tube and tore down the entire pump. I even removed the end of the pump where the NRV lives.

The NRV was damaged. The spring was broken in pieces so I had to put in a new spring and made a new pip. Luckily this one had the brass pip cup so that I could make a new easily. The NRV also did not have a lead washer, so I experimented a bit on this NRV. Instead of using a lead washer I used a Nitrile O-ring instead. The bottom of the pump tube that the NRV screws into is recessed where the NRV fits. Since I had the bottom off the tube, I was able to determine if the O-ring would squeeze out from under the NRV. What I found was that the recessed area retains the O-ring underneath the NRV and does not allow it to escape. Very NICE! I'm not sure this is a feature of other brassies, but has been true of this Optimus 45 pump. So, what I have installed on this stove is an Nitrile O-ring instead of lead washer that fits perfectly and provides a perfect seal, which will be easily replaced with wear.

I resoldered on two leg holders. Two were on the stove, but one was loose, so I took the loose one off and resoldered both back on. It was pretty much a self-training effort to get them on. As a matter of fact, I performed the same exercise 3 times on each one to get them just right - on the job training.

Made a new gasket for the filler cap.

Made new heat proof washers for the burner and underneath the spirit cup.

There was no lead washer in the riser tube, so I made a heat proof washer for that as an experiment. Not sure that will work out if I keep taking the stove apart. It's holding very well, but it is nothing like a lead washer where it will form itself every time you install the riser tube. I would suspect that it will wear over a short period of time and then I'll have to replace it with a lead washer. For now, it seems to be working and I will cross that bridge when I get to it.

I removed all of the patina from the stove since while soldering the riser connector I ruined it with the high heat I was using. So I went ahead and removed all of it from all the other parts. Took a bit of elbow grease to get some of the really baked on layers so now it will grow a nice even patina over the next few years.

One thing I noticed was that this 45 has steel leg holders while others have brass ones. Seems like later ones have brass holders and earlier ones have the ones made of steel. But then I'm not so sure of anything. Any thoughts there would be appreciated.

End of notes.

sam