I have a Sears Kenmore Oven that will not light, mostly just get an orange glow. occasionally if i mess with the knobs i can get it to light but wont stay lit or get up to cooking temperature. it was a natural gas oven but i changed it over to propane when we moved to the country. Also need advise on how to adjust correctly, when the oven was working always had a bad smell and would put out like a black suit or smoke from top of range. any help is welcomed. thanks!