With the sump off, the oil pump was removed. As it is such a crucial part of the engine, it's worth giving it a service while you can get at it.
As well as reading the workshop manual (Manual 518, Operation DX. 220-3), I also watched these videos from "DSSMPassion Citroen" several times over:
strip down - https://www.youtube.com/watch?v=4Lz1XY3812Y
and reassembly: https://www.youtube.com/watch?v=UQ5AHbpn2js&t=142s.
The main aim was to make sure the whole thing operated smoothly and was not gummed up with burnt oil and sludge. I also planned to replace the two springs in the valves.
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| The Bypass Valve and Spring is on the 'Cup'....... |
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| .......The Pressure Control Valve is on the Pump Part |
The first job was to get the pump out of the engine block. Even with the locking screw (located on the tower) removed, pumps can still prove stubborn. With a little use of some Plus Gas and some gentle wiggling and rocking, the oil pump slowly began to yield and in this way was 'corkscrewed' out.
Removing the bracket, the pump body was split into it's two parts. The 'Cup' part actually faces down in the engine and is the part that you fit your oil filter in to.
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| The Oil Pump Is Located In The Sump |
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| Oil Pump Filter Housing - the Bit You See When You Change A Filter |
Splitting the pump gave access to the pumping parts. The engine cam shaft operates the drive pinion which turns the spindle. The inner, four pointed pump pinion rotates within the outer, loose pinion - which itself is free to rotate. This creates the pumping action.
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| Ingenious Pumping Pinions |
The loose pinion was easily removed. However removing the pump pinion that it fits around meant releasing the pump spindle from the tower. This is done by pulling the drive pinion off the other end of the spindle. However my three-legged puller was not up to the job and there was a lot of cursing as the puller's legs were too chunky to get any grip under the teeth of the pinion. In the end I asked Doug up at the barn to press the shaft through using his hydraulic press. If I had to do this again I would try and find a suitable ball joint splitter.
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| Pinion Was Pulled Off - 11 July 2017 |
With that drive pinion removed the spindle was pushed through the body, allowing the pump pinion to be pushed back along the shaft a little. The spindle was quite sticky and grubby at the drive pinion end and didn't want to come out too easily.
Pushing the pump pinion back revealed the flat washer/ keeper and half-cotters that had been holding the pump pinion in place. Careful you don't lose those cotters!
