Fuel Article - Bosch VP44 Injection Pump Disassembled

[Mopar1973Man]

Here it is gang the Bosch VP44 Injection Pump fully disassembled.

Here is the rotor and injection pump assembly.

I stood the rotor assembly up and pull the pistons out of the rotor. Yes, these pins are the 3 pistons pumping together to create the high pressure. 

This of course, is the main shaft, vane pump and cam ring. Take notice to the 3 rollers and shoes below the main shaft. These 3 roller shoes ride in the slots of the main shaft and roll around inside the cam ring.

Here is the timing piston. This is the piston that causes the infamous P0216 code. You can see the piston is galled up and this pump failed with the P0216 code.  

Now you can see the relationship of the timing piston and cam ring. As the piston moves back and forth it advances or retards timing as commanded by the ECM.

Here is the PSG unit on top of the Bosch VP44 Injection pump. The lead on top is the valve for controlling the timing piston by flowing fuel pressure to
the piston. The lead on the bottom you notice has been tapped and this lead is the fuel pin solenoid. Also take notice the electronics are heatsinked to the fuel side not the cover side. This just kills off all the people thinking heatsinks or blowers on the cover are do any good... Sorry it don't.

Close up of the guts of the PSG. That clear gel is not solid as you see I was attempting to get some plastic debris out of the gel and disturbed it. This gell helps the heat of the electronics to dump the heat into the fuel below the plate. 

This is the PSG flipped over showing the sensor for the tone wheel and fuel temp. As you can see the electronics sit over the ribbed section. Again this is to promote heat exchange to the fuel for the electronics. This is another good reason why the 14-20 PSI unofficial fuel pressure are suggested. 

Then the empty VP44 injection pump body. Yes, this VP44 body was damaged beyond what can be used for core. The owner pried the pump out of the gear instead of using a gear puller. That's why the damage to the nose of the VP44 pump body. 

Looking inside the Bosch VP44 injection Pump body where the guts go.

Then the nose of the Bosch VP44 injection Pump where the shaft comes through. 

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