PAS O Ring - yes or no


Doing a rebuild of the PAS pump while the engine is out, and I have the o ring in the kit that seals the two halves of the pump. The pump was working OK and no leaks but there was no o ring in there. What’s more, the groove is interrupted by a locating pin so it looks quite unsuitable. Anyone know if this was a variant? I can’t reassemble with my new o ring - it will just be chopped in half by the locating pin. I assume I just assemble with no o ring at all? BD763110-5258-4D05-8454-B13A4E13C7FA.jpeg

unstable load

Well-Known Member
Sight unseen, I am going to suggest that the pin should maybe NOT protrude above the surface, unless there is another part that requires locating and holding in place, in which case maybe the packing is not for that application, but elsewhere or nor required by part number.

It does not match the repair manual, and there is a groove in the mating part to accommodate the pin. It’s odd as you can’t really assemble it wrongly anyhow!


Well-Known Member
Do you think it’s been messed with or salvaged at the factory from a marginal casting perhaps? The machining of the grooves doesn’t look great does it..but I’ve never taken one apart so they could all be like that?
It doesn’t locate something on the other side does it?

I don’t think so, it looks completely like it’s supposed to be there but the o ring groove is certainly still present. The o ring is a tad small but I think that’s another matter. I don’t suppose I have much choice in the matter anyhow but to seal it back up.


Active Member
Are the two halves of pump just metal to metal as I notice one port at the top of the picture seems to have an O ring in it. Presumably the pin is to locate the cam ring. The SD1 manual shows a large O ring but also states smear the face between the 2 halves with Loctite 275 before assembly.
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