I.D. of fuel injector in microns????

[Jim Cobler]

Does anyone know the I.D. of the fuel injector in microns? I am just curious.

I am trying put some sort of perspective on the contamiants in the fuel that has received so much discussion. When I was considerably younger and my eyes much sharper, I used to work for an engineering outfit that had some rulers marked at 1/256 of an inch. As I recall that was difficult to read with the naked eye at best. If I am not mistaken, 1/256" is about 10 microns. Is it possible for the unaided eye to even see a micron?

[ 03-27-2003: Message edited by: Jim Cobler ]</p>

[Kennedy]

Well, the pin/body clearance is in millionths, and is actually fit with an air gauge rather than measure! :eek:

This is why return fuel volume is so critical. The pulse hits the tip and part is delivered through the spray holes, while part goes past the pin for lube/cooling. If this clearance gets loose, the injector does not deliver/atomize well.

[chuntag95]

Don't know the size of the injector, but I do know the measurements you referenced. 1/256 th of one inch is 0.0039 inches or roughly 4 mils which is equal to 99.22 microns. The average human can see as small as 3 to 4 mils (about the thickness of a sheet of paper), so the 1/256 is about the limit. A human hair is between 100-400 microns. Hope this gives a feel to the size. I couldn't see the hole in the old injector when they replaced mine last week.

[Jim Cobler]

Thank you very much. I stand corrected. I went at this computation from another direction and must have made a mistake.

If we are talking about particules that are far below sight level, I really wonder whether these particules or cavitation is causing the erosion. Keep in mind I am running dual filters so I intend to accept no risk that I can manage.

Thanks again,