[changzuki]

- Centurion's Heart Murmur....
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In a quest to find out the problem involving a vibration and then a potential link with "air present" at the fuel injector(s), the heart of the fuel system needed to be looked into. Sporting its factory "Diesel Kiki" id tag, and unmolested factory Kubota paint, suggested the injector pump to be "OEM" for the vintage D850.
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Identifying the pump using the ID tag is truly a pain in the behind. There's a pitifully small amount of room to try and get one of those "little mirrors on a stick" into a useful position (between the tag and the cylinder head) to see all the stampings on the tag:
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Removing the pump isn't much of a job but in addition to the lines and linkages, does require the intake manifold to be removed:
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In your hands, the injector pump feels quite solid. To call it an injector pump is almost a misnomer.
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There is actually a "pump" for each of the three injectors. Flipping the pump upside down reveals each pump's roller:
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These rollers raise and lower on their own specific separate camshaft lobes:
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The only thing that separates each pump's fuel from the engine's oil are some very tight/well machined tolerances.
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Initially, this little unit looks bomb-proof but further investigation suggests otherwise....
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There appears to be "flakes of metal" present on the topside of the roller area - and that should not be.
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If these little trouble makers are getting into the injector(s) or any other part of the fuel system, then it may answer many of the previous questions, as well as raising some new ones...
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It may also answer the question of what the next purchase will be!
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~CrazyJerry
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