i have a kenmore gas range - my largest burner does not burn evenly all the way around, is much weaker than it once was, and there is soot buildup under the black cap on the regulator. I have cleaned the orifice and regulator to remove the soot, but it comes back and doesn't help the flame. I assume the burner valve needs to be replaced. Sears says part number 5303935236 is the correct part. I have propane - will that part need to be modified for propane or will it work right out of the box?

Thanks.