Think it's an oil jet

[scutter]

Hi,

Whilst stripping the engine for rebuild/painting, thids appeared on the shed floor!!   Any ideas where it's come from, looks like an oil jet.

Thanks in advance.

Dan.

[Nurse Julie]

Yes, that's an oil jet.

[scutter]

Thanks, where exactly can I refit it?

Dan

[DomP]

May depend on model but on 550s they are between the cylinder head and lower cases.  Make sure you replace it the right way up!

[K2-K6]

It may be fine detail, but relevant none the less, they are often called "jets" but are in function an oil "restricting" device.

The crankshaft, mains, big ends etc .... all exposed to full delivery/pressure from the oil pump directly .... this to effectively lubricate at designed for attribute.

The restricting "jets" drop that distribution characteristic to supply camshaft at lower rate as the high pressure etc is not needed.

Leaving them out will give excessive supply to top end of engine BUT then starve the crankshaft of its intended rate in supply. Very important, in other words 

[Bryanj]

Yes one each side at base gasket, also act as locating dowel and only goes one way up

[Oddjob]

Make sure it’s not blocked before fitting. Hold it up to the light and look down it.