Mine, two straight areas, 180 opposite. When set on burner by tabs on burner, then rotated to lock in place. Duane View attachment 274147
@Migwar @hikerduane . 1. Place flat sides at tabs. 2. Turn so that the lip of the burner locks under the tabs. Your inner cap should come off. It may be stuck, but grip it and rotate it until it frees. Best regards Tony
Well noted and many thanks @Tony Press for everything and for putting the efforts to illustrate, it is now clear for me. Many thanks @hikerduane for taking the pictures, and sharing them, much appreciated. I just did as advised and burnt the stove. The upper cap fits the position as instructed. However the same result is there. I have to push the upper cap out of its ideal position to get better flames. My next move, once the stove is cold again, will be to try removing the inner cap as advised. And look from that perspective.
@Migwar You should carefully reshape the tube that the inner cap sits over, so that it is circular along its length and at the top. Also clean the burner and carefully reshape the bent parts. Check the part where the arrow is pointing. Is it fully welded to the burner or is there a crack or a leak? If it’s looks as though it is ok, carefully file the part that’s not quite round, so that the inner circle is not interfering with how the outer cap sits on the burner. Best regards Tony
Thanks, @kerophile I have to triangulate that leak's position now. Hope I will be able to do so. It was really a mystery. @Tony Press any hints/tips on reshaping the tube that the inner cap sits over? regards, Migwar
I leave below some 3 photos. Despite the condition and shape of the tube, I've noticed a type of bulge(resulting from deformation or from the initial welding). The bulge is visible only by light from above and the shadow left. The bulge is also on the same side as the yellow flame side. Not sure this could mean anything if it affects the flow of gas.
Hi @Tony Press I tried to quote your message above, not sure I managed to properly quote to respond though, so I've copied below: Check the part where the arrow is pointing. Is it fully welded to the burner or is there a crack or a leak? If it’s looks as though it is ok, carefully file the part that’s not quite round, so that the inner circle is not interfering with how the outer cap sits on the burner. Asking please about carefully filing the part that's not quire round, will over filing cause damage to the burner's gas circulation? just that. I mean below that point and under the disk is it a space filled with metal or it is a hollow space for gas? Thank you
Hi @Migwar . The part of the the silent burner you are referring to is the fuel vaporisation chamber ( or doughnut, because of its shape). It is a shaped, thin-walled, hollow chamber which vaporises the liquid fuel on its way from the tank to the jet of the burner: See this diagram: Optimus 207b burner exploded view Best Regards, Kerophile.
Well, as I am allocating more time during the winter season, I am back to this stove. I gave this T a full cleaning and the issue persisted. @Tony Press do I have to apply heat to the inner tube before reshaping it? Or it can be done on cold? How do I prevent its circonference from expanding? Thanks in advance.
@Migwar I would first attempt to reshape it by using a steel bar of the correct diameter down the centre of the tube, and then tap the brass tube, using a minimum of force, with a small hammer. It does not need to be perfect, but must accept the inner cap. You want to be able to get it round again without disturbing any of the rest of the burner, especially the brazed connections. Best regards Tony
I leave a picture here showing the yellowish flame which is causing soot. I will try removing that bulge (indicated by @Tony Press ) tonight and check again.
Can also try a bolt or socket to help in correcting the shape. I've used socket extensions to knock dents out of Coleman type stove, lantern pumps. Duane
