172 Idling Problem

[*Badger*]

172 (53 Plate) very noisy on idle (around 800-850rpm) when warm, almost sounds like a diesel, but once the rev's get above 1200rpm its ok, my feeling is oil pressure maybe.
Anyone experienced anything similar or know the answer ?
It sounds to be coming from the rockers/cams sort of area.

All help appreciated!

 

[DAMO 40/172]

i had similar - turned out to be dephaser pully. Does yours stall easily?

 

[*Badger*]

No its doesnt stall at all, doesnt miss, just sounds terrible!