[EMAIL PROTECTED] wrote: > > IIRC the Bosch injection pump does not rely on the lubrication qualities of > the fuel. The pumps in our cars use motor oil for lubrication. > > That's why the reduction of sulfur is not a critical factor in Bosch pumps as > it is in rotary injection pumps that use diesel fuel for lubrication.
The first shop that explained the workings of the inline pump to me, said that the actual delivery pistons are lubcricated by the fuel, which makes perfect sense if you look at a cutaway view of the pump. That is why the choice of whether or not to use a fuel additive, and then if you do which additive is chosen, is so critical and sparks so much debate, as any interference with the action of those pistons affects fuel delivery volume and amount (and of course there are seals issues as well, with some lubcricants). This applies to injectors as well, of course, but you can remove/clean/rebuild injectors more easily and cheaply than messing with the pump. Mac
