Rebuilding a Bosch diesel injection pump
EXIT • Page bottom • Photoessay originally by bricofoy • Also see Injection • Also see Resealing a Bosch Injection Pump • Downloadable PDF: Bosch VE Pumps.pdf • Reference: Compact Automotive Diesels
Yes diesel heads, welcome to my friday evening activity: resealing a beautiful Bosch VE injection pump.
Note: This article does not explain how to replace the shaft bearing or how to set internal pressure. It is only a cleanup and resealing guide.
The pump is in unknown condition, so let's go for a good rebuild with disassembly, cleaning, and complete replacement of all seals.
In general this work should be done under conditions of surgical cleanliness. The slightest bit of dirt will rapidly degrade the extremely high tolerance pieces once the pump is back in service. Thoroughly clean off the outside of the pump before opening anything. Start with a stiff brush and some diesel then use caustic soda and rinse well afterwards.
Work on a clean work surface in an clean environment with no drafts which can blow dust onto your work or where dust can fall from the ceiling. Work on a white sheet with plenty of clean rag to hand and bowl of solvent and a nice clean brush. If you have to leave the work at any stage, cover it with a clean cloth while you are away.
BE METICULOUSLY CLEAN THROUGHOUT.
EXIT • Page bottom • Photoessay originally by bricofoy • Also see Injection • Also see Resealing a Bosch Injection Pump • Downloadable PDF: Bosch VE Pumps.pdf • Reference: Compact Automotive Diesels
Yes diesel heads, welcome to my friday evening activity: resealing a beautiful Bosch VE injection pump.
Note: This article does not explain how to replace the shaft bearing or how to set internal pressure. It is only a cleanup and resealing guide.
The pump is in unknown condition, so let's go for a good rebuild with disassembly, cleaning, and complete replacement of all seals.
In general this work should be done under conditions of surgical cleanliness. The slightest bit of dirt will rapidly degrade the extremely high tolerance pieces once the pump is back in service. Thoroughly clean off the outside of the pump before opening anything. Start with a stiff brush and some diesel then use caustic soda and rinse well afterwards.
Work on a clean work surface in an clean environment with no drafts which can blow dust onto your work or where dust can fall from the ceiling. Work on a white sheet with plenty of clean rag to hand and bowl of solvent and a nice clean brush. If you have to leave the work at any stage, cover it with a clean cloth while you are away.
BE METICULOUSLY CLEAN THROUGHOUT.
1 Here you see the starting point, a pump, seals kit with the control lever seal and driveshaft seal. A good lubrication of parts that push, contact, or slide is essential during the reassembly. Try to avoid disturbing the adjuster screws on the outside of the pump, otherwise you will need to take it to an injection specialist who has high-pressure gauges and precision flow measurement equipment to properly calibrate the pump. These adjustments are customized for your vehicle and engine and normally never need to be changed if doing a maintenance rebuild or replacing seals. | |
2 Here it is about an hour later. I did not take pictures of the disassembly, go in reverse from what follows if you have doubts for disassembly. Important settings to record:
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3 Get started by doing the distributor head hydraulics, it will always be so de facto. Below are the different components of the delivery valve holder. bushing, spring, shim, needle, and new sealing washer. | |
4 The copper sealing washer on the delivery valve holder. | |
5 Removal of the distributor head should be done with the pump held with the fuel outlet stubs upward, with the fuel lines removed. The head should be pulled slowly and straight upwards to prevent parts from falling out of the pump. There is a long, tight-fitting shaft, the distributor plunger, which is the piston of the high pressure pump. This plunger needs to be removed carefully. Some springs will fall out of place but it is not important. When removing this plunger shaft its position relative to the drive shaft should be marked since it can be reassambled in two positions, depending on the cam-plate. There is a pin in the cam plate (skip to step #53) that forces the plunger to be properly aligned on the cam-plate, but the cam-plate can be assembled either of two ways. One way is 180 degrees off and will result in the pump injecting at the top of the exhaust stroke, not on the compression stroke. This camplate with its alignment dogs is shown in step #52 along with further warnings. You will re-install this plunger starting in step #57 where several photos are shown. |