Why are Jake brakes less common?
I believe they are installed on more vehicles than ever but city noise abatement laws prohibit their use in populated areas. They are used often in the mountains. There are even integrated with new engines delivered from many manufacturers. They work on 2-cyle and 4-cycle diesels. See www.jakebrake.com Diesel carbon clogging. I am not a diesel engine designer, nor do I play one on TV. If this sounds wrong to you, it probably is: My understanding is that most carbon collects when the engine runs relatively cool. Short idle periods do not let the engine cool down very much, so frequent idling is not a problem, but extended idling is. One diesel efficiency is that at idle and low loads, the diesel can run with mostly air and a tiny amount of fuel injected just to keep things running. In contrast, a conventional gasoline engine must draw a cylinder full of fuel/air and if the mixture is too lean it will not ignite. So there is a “floor” below which the gasoline engine just burns too much f
