On occasions on startup, the oil pump doesn't prime. This is most likely
when the motor has been running for a while, has been shut down, and
is restarted shortly thereafter.

The axial clearance of the pump's gears in the pump body is close to
midrange of Volvo's specification, as is the gear pair backlash.

The dipstick O ring seems OK, as does the fibre washer between the
dipstick housing and the block. The dipstick tube silver soldering into
its housing is OK. (On these engines the dipstick tube doubles as the
suction line for the oil pump.) The wire gauze suction filter is clean.

I'd much like to hear from anyone who has had this problem and fixed it.

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