PFM, just like Craig says! The primary reservoir of the oil is, of
course, the sump. ST cleverly designed an hydraulic anti-gravity
device driven from the camshaft that lifts the oil up and sends it
hither and yon through various passages to places near and far needing
lubrication (and some which just happen to look too clean.)
On the spitfire engine, the supply of oil to the rocker shaft is
regulated by two flats machined in the rear camshaft bearing. When
the flats align with the main oil gallery in the block, oil flows
through a scroll cut in the bearing to a passage leading up to the
rearmost rocker pedestal, whence it flows into the hollow shaft. So
the rocker gear gets a squirt of oil twice per camshaft revolustion
which just happens to be once per engine revolution.
HTH,
Donald.
> From: Craig Smith <CraigS@iewc.com>
> Date: Wed, 14 Aug 2002 18:32:27 -0500
>
> Engine 101
>
> The oil gets to the rockers through the cam.
> If you ever pulled the cam from an engine the back or sometimes the front
> bearing has spiral grooves on it.
> The cam turns at a different RPM than the crank due to the pulley diameter
> diff oat the chain.
> A good close clearance at the cam bearing with the grooves causes the oil
> supplied at the bearing to get forced to an oil galley hole that feeds up
> through the head into the rocker assembly.
> The rocker assembly has an oil galley inside.
>
> It's really magic, and all that stuff up above, I just made it up !
>
>
>
> -----Original Message-----
> From: John Hobson [mailto:goalie_john@yahoo.co.uk]
> Sent: Wednesday, August 14, 2002 7:00 PM
>
> I do have one question - how does the oil get up to the rockers, I can't
> figure this out?
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