Optimus 155 dismantling/reassembly

Quickstarter problem Optimus 55/155 generation 1

Spending quarantine fixing some Optimus 155 marine stove

 

Hi Kerophile
I use a 155 on my boat in Sweden and I now have a very small leak on one burner coupling, replaced the burner, polished the burner bottom, replaced the alu cone, and still not OK, any idea ?

 

Hi @presscall , Please can you help this sailor (See Above)

Best Regards,
Kerophile.

 

You seem to have covered all bases already, provided ‘polished’ has ensured there are no nicks or cracks in the mating surfaces. Copper grease will often ensure a seal when jet nipple threads are a bit leaky in the burner mount. Your issue seems to be a suitable application for the substance too. It seems likely it works by achieving the best possible sealing by eliminating friction of the mating surfaces.

 

@presscall John do you also think that maybe over tightening the alu cone could bring to the seal failure?

It shouldn’t happen, but once I have found a cone that basically slipped fully inside the burner base.

Just saying, clearly in this situation it’s hard to know what’s wrong without the stove in the hands.

Nicola

 

Are you able to tight the nut under the alu cone more? First loose that bigger nut (which just locks the burner to stove body) as down as you can that it doesn't restrict tightening of the burner mount nut (which is the inner nut).
Also check that burner has suitable mating surface with alu cone. If burner is made by some other company than Optimus mating surface could have a form that it doesn't mate so well with alu cone. If needed you can make mating surface in burner more better to alu cone with a drill bit.

 

Unsympathetic stove user to have distorted it to that extent! Over-tightening, or a succession of tightening to deform the seal. OP says though that he’s got new seals.

 

Yes John, for sure something strange. The cone didn’t look deformed though… maybe a wrong sized cone seal for that burner? The base of the cone seal was slightly larger than burner base, so probably an inadequate cone for that burner.

Nicola

 

Maybe a self made cone / not original spare part?

 

@Afterburner didn’t look home made but maybe, yes, not original, that’s what I mean.

 

So great to see so many feedbacks, thank you guys ! I would like to share my journey with my 155, that I have been using on my sailboat for 3 years now. I had another 155 with preheat I had bought new in 1981, and I sold it with " Oanagogos" you can still see her on Marinetrafic ! in Australia ! Coming back to my problem, I have tried to replace one of my burners with a new one from Tilley. Issue is that these burners are OK if threaded on top of a riser tube, but not optimum for a compression fitting, since the tube end bottom is not really machined smooth. So I installed another old burner from another 155 I found in Sweden, and it works. I also tried a Hansa burner, but it really challenging to preheat. Any idea to improve the Tilley burners ?
I have sent a message to Julian Shaw at Tilly to suggest offering machined burners at additional cost, no answer

 

Hi Afterburner from Finland, I could not find any new Optimus regulated burners in Sweden, FOGAS is out of stock, any idea from your side?

 

@jean francois lutz I share my thoughts.

Looking for new burners is possible, on Tradera they appear now and then.

In any case I think that also the most used burner can be easily renewed with a new needle and jet, easily available also on fogas.

If the burners are full of carbon you can heat them with a torch and use compressed air to burn and remove all the carbon from inside the tubes, there are different discussions about this.

Nicola

 

Hi Nicola, we are mostly users, not collectors.
We had a 155 with vaporized kero preheat for 5 years in 1981-1986, and never changed spindles or needles, but it eventually failed , leaky burner...
Back to sailing now with a 155 with spirit preheat, I now fixed my small vapor leak at the compression fitting by replacing the new burner with an old one original Optimus. Parts from the only supplier left in UK are mechanically not perfect, and not always interchangeable, so I fully agree to look for original (even used) Optimus parts and matching spares. I had to cut about 1 cm both sides since it did not fit the boat galley !

 

Hi Presscall, I have responded finally it is OK, I replaced the new burner (Tilley) with an old used original Optimus, and it works. I like your idea about copper grease, does it stand the heat and do you know a brand name for this product ?

 

Yes to the heat and ‘Copaslip’ from the Molyslip company. Marketed as ‘high temperature anti-sieze compound’. Other equivalent brands out there no doubt.

 

Apologies for late reply...

I was wondering if you had an Optimus burner as a spare part but it was Tilley. Optimus 207 burners have been obsolete for very long time so they are extremely difficult to find. Time to time some auction sites have them, but that also happens very seldom.

Luckily you found used Optimus regulated burner and that solved the problem.

 

Thanks. I think Tilley s are OK to replace burners mounted screwed on a riser tube but not really designed for a compression / cone fitting. I tried a Hansa burner, no leaks but almost unpractical to preheat with spiritus. I had a discussion with Herr Dorflein, the manufacturer of Hansa and he brought a point regarding the fuel, it looks like paraffin / lysfotogen / petrol have a fairly wide range of vaporizing temperatures, it must be 180 deg. and he said he had found up to 300 deg. in some cases. Nevertheless, preheat time is at least 2 times (8 minutes with a fiberglass wick) more than original Optimus burners. Quite long for a morning pot of coffee on the boat, so I will stick to using used original burners. As you said, I found many 155 stoves on Tradera, and bought 2 of them to have spares. I also found an original "new old stock" single burner.

 

Hi and thanks for a great guide! I'm new to the forum so I figured I'd post in an existing thread rather than start a new one...

I have an Optimus 55/155 in my boat, but it has developed a leak in the left quicklighter fuel/air pipe. Specifically it's the pipe coupling that's leaking; it seems that the rounded bit at the end of the thick outer pipe (is that called an olive?) seems to have deformed and is no longer sealing properly. I tried tightening the captive nut and that fixed it for a while but then it started leaking again.

I've had it suggested to me to try to seal this coupling up with a thread sealant, specifically Loctite 270 - does that sound reasonable? I see in the spec sheet that it can withstand at least 180°C for a very long time (thousands of hours) but starts gradually weakening above 200°C. I'd guess this coupling really doesn't get that hot so that sounds fine to me. I have no experience working with this thread sealant so I don't know how much to apply but I guess I can experiment? Are there any other options I'm overlooking?

 

@kblomster
Loctite 270 is classed as ‘high strength’ which I’d avoid using. A joint that can be undone without difficulty if necessary (if the sealant doesn’t resolve the leak) is desirable.

I recommend a copper-based anti-seize compound that I’ve used successfully to seal jet threads in burners. It’s good for temperatures up to 1100C.




Don’t apply it too liberally such that it finds its way into the jet!