High Pressure Fuel Pumps: Notes

WARNING: This page is about a different car, the 2015 Jaguar XK, 2014 Jaguar XK, 2013 Jaguar XK, and 2012 Jaguar XK. However, it is still accessible from the selected car via links, so may be relevant.

ITEM	DESCRIPTION
1	Crankshaft
2	Auxiliary drive chain
3	Auxiliary camshaft
4	Tappet
5	HP fuel pump - No. 1
6	Acoustic cover

The two HP fuel pumps are identical mechanically-driven pumps installed on the RH side of the sump body, behind the generator. An O-ring seals each of the HP fuel pumps in the sump body. The rear HP fuel pump is identified as No. 1 pump; the front HP fuel pump is identified as No. 2 pump. An acoustic cover is installed on each of the HP fuel pumps.

The HP fuel pumps are single-plunger pumps. The plunger of each pump extends through the sump body and the carrier of the auxiliary camshaft. A tappet on the end each plunger is operated by a two-lobe cam on the auxiliary camshaft. A spring installed on the outside of the plunger ensures the plunger and tappet remain in contact with the cam.

The auxiliary camshaft is driven by the crankshaft, via the auxiliary drive chain, at engine speed. The auxiliary camshaft is timed to match the pump delivery strokes with crankshaft position.