Whats wrong with my Optimus 8r hunter?

Can anyone help me with what may be wrong with my Optimus 8r hunter?
(please note at 0:11 and 0:19 i was turning the valve)
Im having problems with what i think is being slow to start up, i dont know if its a blockage, but appears to be a pressure fluctuation, as you can see and hear in the video, the flame is going chuf, chuf, chuf, and is not constant.
This however improves and slowly roars into life after 10 mins or so, i tested boiling 1 litre of water, and it took 16 mins from starting the stove, but i did another test again, while the stove was still going and only took the usual 11mins.
Some days however, i dont have this problem and ive had it worse than what the video shows too.
I must point out that i have replaced the wick, seals nipple and cleaning needle about 3 years ago, and only has a few uses each year, has been running good until now, and this problem seems to be intermittent, the only thing i can put it down to is me changing to coleman fuel, but that is one of the best fuels to use, and i initially had good results with it when i first tried coleman fuel, other than that these were a very good stove for their time and had been produced for several decades.

Category:

Sports

Tags:

• Optimus
• primus
• stove
• spiritburner.com
• spirit
• burner
• spiritburner
• 8r
• hunter
• 111
• 22
• no5
• kerosine
• coleman
• tilley
• fuel
• lpg
• propane
• butane
• kovea
• epigas
• camping
• gaz
• brunton
• nova
• msr

[jamesccostello]

Coleman fuel never seemed to work with mine either. My advice is to you is to try white gasoline. If you cannot find white gasoline, you could try unleaded automotive gasoline, but automotive gasoline could be a health risk. Definitely do not use leaded gasoline, or MTBE gasoline.

The manual that came with mine says that it absolutely will not run on automotive gasoline, but I'd guess that it had to do with the tetraethyl lead in leaded gasoline clogging the jet.

[nzoomed]

interesting you say that. i switched to coleman fuel from varius brands of white gasoline/white spirits after noticing it left black soot on the pot stand, i used coleman fuel and no black soot initially the first few runs were great with coleman fuel, but after taking on a tramp, it let me down, but it seems intermittent, when it works on colemen fuel without problems, its great, no soot and slightly hotter, however ill consider going back to my old fuel and see how that goes :)

[idahostoveguy]

It should sound like a helicopter. What that sound indicates is:

1) a carbon filled valve body. The way to fix that is take the stove apart and clean out the inside of the valve body, and tube coming from the tank.

2)There's also a wick that may have come out of the fuel tube and is floating around in the tank or is burned up. Easy to fix. Get 100% cotton mop string and replace it.

Have fun, these are great stoves! It should last you another 50 years!

[nzoomed]

@idahostoveguy

Im tending to think its carbon in the valve body.

Its very intermittent, i used it again recently without any problems, i bet it will happen again next time i use it.

The wick was replaced quite recently, but i never took the valve body apart for inspection, i probably will take it apart and check everything anyway and give it a clean.

[IanHolwick]

Try "Panel Wipe" - cheaper alternative to "white gasoline". Used in paint shops, buy from automotive supply or search online.

[rikuk3]

I'd fit a new wick inside the burner but these do tend to 'Chug' when use, don't worry about it too much.

[richardhummell2497]

I had a new one back in the early 70's! I tried all kinds of fuel and it ran best on unleaded gasoline. I would only fill it 3/4 full and then put the cap on. Next place your hand on the fuel tank to warm the fuel and pressurise the tank. next open the control valve to soak the rope in the cup at the bottom with fuel. Light the rope and wait till it's almost out and then light the stove it should chuff for about 2 mins or so then roar consistantly. Good luck! I wish I still had mine!l

[varmintslayer311]

@idahostoveguy This is good advice. I replaced the wick in mine after I noticed a pulsing flame. My wick was the culprit. Also, you can improve fuel efficiency by using just enough wick that will allow liquid fuel to rise from the jet when you prime with your hands. :-) The flame tips need only touch the bottom of the pan not engulf it.

[17lbP110]

Coleman fuel is white gas, ie, gasoline without the additives needed for automotive use, My 8R sounds just like that so I don't think you have a problem. The flame is blue which means you have clean combustion. If it turns yellow, you may have dirty fuel or clogged tubes,

[ahoyhoy79]

is there a filter at the intake point on the pump? perhaps that is clogged. just my 2 trillion zimbabwe dollars

[jamesccostello]

I forgot to mention that I've been running pump gas for the last five or six camping trips without problems.