Model Diesel: 32mm bore, 38mm stroke, indirect injection

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I decided to take Roger's advice and grind the grooves in after heat treatment. Here's my setup, I just put a dremel cut-off wheel and arbor in my milling collet.

Worked pretty well. I covered my ways with rags before grinding, the abrasive dust is not good for them. My mill only does 1100 rpm at full speed which is really too slow for a grinding wheel. Still made a lot of heat, I had to squirt coolant on it between passes to avoid taking the temper out of the part!

This part lapped in much better. Interesting observation, it was actually lobed with 3 high points. I suspect the low points lined up with the chuck jaws on the lathe when I was turning it. I've got it cleaned up slightly oversized, I'm not totally happy with the surface finish in the barrel (grit was too coarse) so I think I'll finish by lapping the barrel bigger to match.
Having done all this, temptation took over and i put the head on and cranked the engine with a more powerful drill in low gear. There was a noticeable smell of burnt oil, and so, optimistic, I sprayed some 'start ya bastard' into the intake port and tried again... a large cloud of white smoke shot out of the exhaust as the valve opened. We've achieved compression ignition!

I used some "start ya bastard" on my Merlin V12, that was the only time it ever backfired, and given the large volume of the intake manifold, it was quite a backfire resembling a gun shot more than an engine pop, not using it any more :-( !!!

anyway, following this thread with interest as I have a Hansen A-frame Diesel in the works but have not yet attempted the fuel pump and injector...
Más progreso: ¡tengo un (más o menos) inyector que funciona!
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El patrón de pulverización podría necesitar algo de trabajo, sospecho que esto podría beneficiarse al lamer la punta de la aguja junto con la boquilla del inyector. El otro problema que tengo es que el resorte del inyector no es lo suficientemente fuerte como para hacer que la presión de "pop" del inyector alcance mi objetivo de 10 MPa. Creo que esto se puede solucionar simplemente doblando los resortes.

A continuación se muestran las partes principales del inyector, antes de algunas operaciones de fresado que necesitaban para el acabado. Como referencia, el tornillo de cabeza hueca que los acompaña es de tamaño M3. Los componentes del cuerpo del inyector son de acero inoxidable, mientras que la aguja es de acero para herramientas.

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Dónde puedo encontrar los dibujos de ese inyector

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