I'm rebuilding my engine, in the depths of the Haynes manual it says these oil jets should always be replaced. Does anybody know of a sensible supplier to supply them? My local ford garage had never heard of them.....eventually they found them on the system and they want £17 EACH!

Is replacing them essential, can they be cleaned? Apart from reading this line in the Haynes manual I'd never seen replacing them mentioned.

If the engine has been run on synthetic oil they are unlikely to be clogged you can check by blowing through in the reverse direction with compressed air.
If you still want to get any varnish out them soak them in gun wash thinners for a week and then blow them through in the reverse direction with compressed air.

[Edited on 30/1/14 by britishtrident]

The engine was "like new" inside. Incredibly clean, crank etc all in perfect condition.

I'll give them a clean and soak, thank you.