My XJ makes a check-check noise at idle. What causes that?

[radare]

My XJ makes a check-check noise at idle. What causes that?

A check-check-check noise coming from the crankcase is usually caused by a worn oil-pump drive pin. The clutch basket houses a metal pin which supports the drive gear for the oil pump. As this wears, the slot the pin sits in becomes elongated and the gear moves around on the clutch basket, creating a check-check-check noise. This is commonly known as the Seca II clutch rattle.

To confirm that the noise you are hearing is the clutch rattle, pull in the clutch and listen to the crankcase. If the noise goes away or quiets significantly when the clutch lever is pulled in, the noise is very likely caused by the oil pump drive pin.

Repairing a worn drive pin is not difficult but does require removal of the clutch and clutch basket.