'87 300 TD Injection Pump Delivery Valve Piston Position
 

Located beneath the injection pump delivery valve holder is:

Compression spring

Copper seal

Delivery valve

Delivery valve carrier


Beneath this carrier is a piston that has a central vertical bore; near the top is a horizontal bore that communicates with the central bore. Further down the piston is another horizontal bore that also communciates with the central bore; this lower horizontal bore is 180 degrees removed from the position of the upper horizontal bore. Finally, below the skirt of the piston is a vertical notch that is approx. 70 degrees to the right of the upper horizontal bore.

Question is: what is the proper installation position of this piston as it is installed into the body of the injection pump?

my book does not show a view of the injector delivery componants, could you disassemble another injector to find out proper placement? BILL

I assume the question means you have pulled the sleeve/plunger set out and need to install in the correct position.

Unfortunately, you need to put the pump on a test stand to get it right unless nothing else moved -- rack adjustment will be the same, but you need to put it back exactly where it was. I don't know if this pump uses a "arm" or a gear to rotate the sleeve/plunger -- you may be able to get it back on the right tooth if it's a gear, and it it is an "arm" you only have to get it onto the ball.

Either the plunger or the sleeve (dont' know which in this pump) rotates to control end of delivery position and hence amount of fuel delivered. If the sleeve is in the wrong position, start of injection and end of injection will be wrong, so you incorrect amounts and timing of fuel delivery.

Peter

The sleeve is the component that was removed... the plungers were left in place.

On this pump the plungers rotate... their position is controlled by a gear driven rack.

Correct position of the sleeve was the matter at hand... turns out that the bores housing the plungers have a small pin near the bottom. The notch in the skirt of the sleeve slips over this pin, thereby properly positioning the sleeve and preventing its rotation within the bore.

Nothing else was moved, so hopefully removal of the injection pump will not be required.

Should I ask what exactly you were doing inside there? :eek: