The hotter RC boilers are, the slower they consume fuel for the same rate of steam production. I know this holds true for solid-fueled boilers; I see no reason why it should be any different for liquid-fueled boilers.When the liquid fueled boiler is at max temp, does it decrease the amount of creosote it consumes? I though 12 coke ovens would be enough to keep it supplied, but I'm using creosote faster than I'm making it. I really don't want to have to make more coke ovens.
Also, Railcraft adds a Firestone that can be charged by throwing it into a lava lake, then placed into a boiler to heat it up much more quickly than just burning fuel normally would. For solid-fueled boilers, the firestone can be placed directly in the fuel slot; I don't know if there's a way to get it to heat liquid-fueled boilers.