Optimus Nova (Brunton) Fuel Spew

Hi guys,

Me again.. With another problem..

Recently when I have been disconnecting my stove from the fuel bottle, fuel has been spewing out. When I say spewing, I'm not exaggerating. I just lost 150ml a minute ago. All pressure had been released by turning the fuel bottle over, but when I disconnect it the connector gets jammed and the fuel spills.

The plot thickens. When it stopped and I messed about with it, the slider just went back and forth, so I figured it was faulty and would need taken apart to investigate - especially as fuel seemed to leak no matter which way it was slid. However, after 10 mins, it locked back in the correct position and fuel stop spilling.

What the hell is going on!? Heeelp me please.

P.S apologies for my poor knowledge of the different components, I have tried to explain as best I can. Pic illustrates the "slidey thing".

Regards,
Mark

 

@Mark jolly
The slidey thing is a CEJN female connector.

Here it is dismantled, male connector at right-hand side.




I posted a how-to service guide HERE. I include in there thoughts on a spare source for O-rings, one of which has most likely packed up (torn/split) in yours.

You could buy a new connector, but they’re hellishly expensive.

Good luck

John

 

Fantastic John, once home I will attempt to dismantle using your guide to establish the fault.

Is there such a thing as a safe way to use it in it's current state? I am camping with the kids and I just need one more days use from it.

Thanks,
Mark

 

If it leaks when disconnected... do not disconnect. Does that work?

 

@Mark jolly
What Ken (@snwcmpr) asked. If leaking when connected it’s a no-no. Sorry!

 

When connected, all fine i.e. no leaks.

 

I have also come to find my stove is losing pressure rapidly. 30 pumps lasting barely 15 minutes. It starts spluttering like when you have the fuel bottle over to the off position.

Could this all be related?

Thanks,
Mark

 

It could, though I’d expect an air leak would have fuel not far behind. Go carefully!

 

How is the fuel pickup tube alignment?

There may be more than one problem.
If the air pressure is not released when the tank is upside down... quite possibly the fuel pickup tube is not 'in the air' when upside down. And thus, not 'in the fuel' when set for use.

Just trying to guess.

 

Tube alignment is good. That was one of the first things I checked (OK, the only). However, the problem I am experiencing is exactly as if that was happening. It happens a few mins in when the stove is hot. Pressure doesn't seem to play a part either.

 

Sorry that it messed up the vacation. Did you test the stove before you left?

 

I am managing at the moment by flipping the bottle and then unscrewing from the bottle prior to disconnecting. Inconvenient, but the safest option I can find so far.

Did I test before I left, yes I use the stove regular for mountain expeditions, but watching some YT videos tonight makes me realise I have been losing power in my stove gradually over the months without realising it. The fuel spill only happened on my last trip, which I put down to user error by not adequately releasing all bottle pressure, which I now know wasn't the case.

Not sure you'd call it an upgrade, but could I replace the pump and hose to the new Nova one? Hose is £15 and pump £45. Is that even an option?

Thanks,
Mark

 

I don’t own a latest generation Nova so can’t confirm that the stove-end screw fitting on the new hose is compatible with that on the stove inlet pipe. It looks like it should be. Anybody?

 

Hi all,
I can confirm that the stove end screw fitting is the same for all generations of the Nova, so it is possible to fit the newer bayonet hose and pump to older burners.

 

OK, does anyone know how I get the sleeve bit off the CEJN connector? Pic attached for reference.

Sorry if I sound a bit simple...

 

Wonderful, good to have that as an option, albeit a costly one.

Do you know of anyone that has done it, and do any of you foresee an issue with me doing so i.e. compatibility issues.

 

@presscall did a thread on just that process.
he referenced it above.

CEJN fitting strip-down

Be careful not to lose the small bits when you take it apart.
I did lose the balls, and had to order some. I now have 250 of them.

 

There's a joke possible there!

Don't mind me, hat, coat, door!

 

Move along, nothing of interest here.

 

Oh well, that's that then. Everything was in great condition, but as I was putting it back together the brass bit snapped. My fault as I applied force when it wasn't necessary. You will see from the pic below that the o rings were good, also the part I broke.

Apologies for missing the part in the tutorial about getting the casing off. I went over and over it but must have been looking for something else as I clearly kept missing it.

Thanks,
Mark