Good day every one. I Have recently obtained 2 Coleman 201 kerosene lanterns. After restoring and playing with them a few times i noticed that the one lantern has a halo of flame burning outside the mantle. The the lantern does not do the following: No Blackening the mantle Not Burning dim Not smelling bad. Note: burner screen was replaced by me with a stainless steel mesh matching the same hole spacing as the original. The burner I got never had one in so i had to make a plan. Both lanterns has the same mantles on The halo around the mantle seems to me a bit too big for comfort. So i did the flowing tests on the two lanterns by swapping some parts around... Swapped the generator tips.... No change (Halo is still present on the same lantern.) Swapped the whole generator...No change (Halo is still present on the same lantern.) Swapped the burner frame...Change! (Halo seems to be occurring on the same burner frame) Inspected and cleaned out the air tube and removed the aluminium collar to ensure no airflow blockage...No change (Halo is still present.) Inspected the u tube and venturi tubes...No change (All clean no obstructions.) Played around by extending and retracting the burner tube with the lock nut...No change (halo is still present.) Inspected the burner screen No change...(replaced beforehand with stainless steel mesh with the same hole spacing as the original, the burner came without a mesh so I had to make my own.) Any ideas? originally the one lantern was complete and the second one i have build up from spares. Is there any chance that the Venturi or burner frame could be from a 200a lantern and this is screwing with my airflow to the mantle?