Hi all. Thanks for the great site - it helps a lot. Just bought a used Optimus/ Primus 99. The stove fires up quickly and pressurizes, but this stove has two issues I am concerned about: - slow heating (low BTU output?), takes about 12 minutes for 500 ml of water to get a rolling boil in the case pan - in an ideal (kitchen) environment. [This time seems slower than expected and original company estimated time in instructions. Is it a wick problem?] - during my second firing of the stove, inside the kitchen, I noticed that the stove began to sprout small flames* at the jet nipple and where the adjustment key touches the stove - *once the stove was very hot (about 10 minutes of use). I have not tightened down the parts yet. PS. Also - has anyone tried to use a bike pump (presta) to pressurize a stove with the mini pump cap? As a cycle tourist I try to travel light so why bring a pump for both the bike and stove if one will do the duty for both?
Hi The 99 is a great stove. 1) 12 min is slow, but stoves never go as fast as the box says they do. I think they consider the small bubbles of a early boil to be boiling. Make sure the tank is a maximum if 3/4 full brush some soapy water around the tank cap to check for leaks. 2)You can tighten the stuffing box where the control goes into the burner a little to stop the flame there. (sound like your jet is loose too). 3) You can use a bike pump but it is much much too big and can cause dangerous over pressuring. The mini pump is very light. I hope that helps, happy cycling
I seem to have the same problem, but with my fine Radius 42. It sort of sputters and flickers just around the jetnozzle. I have pricked it. lots and lots.. Can it be something with the wick? Or just plain dirt in it? Rgds Uffe
Hello, If I remember right the Radius 42 does not have a wick. I believe there is a brass screen in the feed tube from the tank to the burner though. I may be wrong. You might just have a enlarged jet causing problems. Jeff
Hi Jeff The 43 has no wick. While I don't have a 42 the ref gallery shows them to be the same as a primus 71 which does have a wick. Uffe, I would try your 42 with a different tank cap and see how it runs before attacking the wick. Replacing the wick is easy enough but the stove may not want to be taken apart.
In every instance that I got a small flame around the base of the jet, tightening it up a bit has solved it. Flames around the spindle require tightening of the collar. If you have to tighten it so hard that you can no longer turn the key/knob to control the flame, the graphite packing probably needs to be replaced.
Hi The Radius 42 has the filler cap on the bottom of the tank so a leak here would be pretty easy to diagnose. It also features a safety release valve that can require adjustment to seal see here. Instructions Or the seal inside may be beyond adjustment and need replacing.
Much thanks for the aid YellowDog. I tightened things up and the 99 seems to be running better - a little faster rolling boil times - and no more extra flames.
