Newb here. Thank you in advance for any tips or suggestions. I have an Optimus Polaris stove. Bought it 2 or 3 years ago, and have only used it about 4 times. I've only burned liquid white gas in it. On each occasion it worked well, no problems. But about a week ago I tried to use it, and have the following problem, which I can't solve: 1) I install the pump into the fuel bottle, pressurize the bottle with the pump, and then connect the hose from the stove to the pump. 2) From there I follow the pre-heat instructions: open the valve on the stove for about two seconds until liquid fuel appears, close the valve, then light the liquid fuel. As the flame burns down after about 30 seconds or so, I then crack the valve a bit expecting the "jet engine" sound and a nice blue flame. Instead I either get A) the sound of pressurized air, but no ignition or B) ignition, but with much sputtering and no steady, solid blue flame...and then the flame goes out and I'm left with just the sound of pressurized air. I've taken the stove apart and inspected the o-rings. All appear undamaged and pliable. I've replaced the jet and the cleaning needle with new ones, though the old ones looked OK, just a tad discolored. The pump works fine, there are no fuel leaks, all connections are tightened down snugly, but---after pre-heating, I either get no ignition, or a brief unsteady ignition which then extinguishes itself after several seconds. Needless to say this is frustrating, especially when the stove worked perfectly the few other times I've used it. I bought a replacement parts kit should I need to replace anything. I'm now about €200 into this stove, with the initial cost and the cost of the repair kit, and I'm wondering if I'm the only guy on the planet who has come to dislike this stove and have the exact opposite experience that most people have with it; that being, it works like a champ and functions flawlessly. Any tips, suggestions, or ideas would be much appreciated. Thank you!
Look at the fuel pickup. There appears to be a lack of fuel, but you get air. So the fuel line is open, but the fuel is not getting into the line.
Thank you for the tip. The fuel pickup is the short right-angle piece on the pump shaft, right? And just to be clear, I do get fuel as expected when opening the valve to introduce fuel for pre-heating. Do you know why it would allow the fuel to flow at that stage, but not later AFTER pre-heating? Thanks again for the tip!
I do not know this stove enough. You hear air after fuel stops flowing? That is a great thing to know. I have general ideas. Bottle movement changes fuel pckup. Fuel pickup is leaking. Fuel pickup is not secure. Low fuel level. Etc.
@John Smith I apologise in advance if I’m stating the obvious, but the fuel bottle is laid on the side with ‘ON’ on the pump uppermost?!!! No, that’s the air outlet, via the non-return valve. Other than that, fuel starvation due to a partially-blocked fuel filter, as I discussed HERE in my write-up of the contemporary Nova (a Polaris without the lpg option). Extract of that bit: Probably because the jolting of the fuel during pumping will have allowed some fuel to seep into the fuel line through the partially-blocked filter. John
@snwcmpr It wouldn’t, if the fuel tube was intact with no pinholes/cracks above fuel level - as you suggested might be the case - that’s true, Ken.
Thank you for the link; much appreciated. I already had the manual and consulted it, but didn't get troubleshooting tips for this specific problem.
Thank you for setting me straight on the fuel pickup. I got a little confused on that, ha! I'll check the fuel filters. I have spares in my repair kit. It would surprise me if they're blocked, though, because I've never used anything but white gas in the stove, always poured into a clean bottle. Meantime, I found this very informative video that shows a complete teardown of the stove, and how to check it for proper fuel flow: Thanks again to everybody for the help.
Thank you for your reply. Yes, I had the bottle in the proper position, with the ON label facing upward. In the past, when using the stove, it worked perfectly. I only used it about 4 times in 2 or 3 years, so on this most recent attempt I re-familiarized myself with the proper operation of the stove by watching videos and re-reading the manual. Everything works as it should, up to the point where the pre-heating has happened and it's time to turn the valve back on to create the "pressurized blue flame" we all know and love. That's the point of failure.
@John Smith A partially blocked fuel passage where the spindle enters the burner could make the mixture too lean for proper ignition. I recently worked on a new to Polaris that worked fine even though I could not hear any air passing through the jet while testing for leaks. In my case the stove worked fine even with a clogged filter in the fuel pickup tube. Since you say you can hear air, and you've already replaced the jet and needle, then the passage might be blocked. I would recommend removing the spindle, jet and needle and flush out the fuel path. Aiming a flashlight down the burner assembly you should be able to see light though the regulator tube. BTW, i replaced the white filter with a new sintered bronze from the kit and now my Polaris hisses normally, I would also recommend cleaning the end spindle with a brass brush to remove any deposits.
I agree with all the advice posted. Initially I would have assumed it was the fuel pick up or the little the wrong way up. With that eliminated, It is likely blocked up, but hot enough to let some fuel vapor through. I would be cleaning the control valve. Removing the jet to see what the fuel flow is like without it in place. Reducing or increasing pressure. Changing fuel Removing the surge / filter from the fuel line ( in the fuel line/ burner connection). Make sure the cleaning needle isn't stuck it the jet. It's a great stove, try and enjoy tinkering with it.
When you get the pressurised air sound, do you see any vaporised fuel looking anything like smoke? Is it possible that your flame spreader plate has taken some impact and is bent from its original form? The depth where it sits in the burner bell affects the fuel/air mixture ratio. My nova refused to ignite when the plate was accidentally pushed too deep. Maybe you could try altering the position and see if it has an effect.
