The Volvo gods must have been watching over you. I
killed two diesel engines in my 1980 265DL that way.
Damned air intake under the car sucked up water
and bent the piston rods/ cracked the block $$$$.
The first time the water was deep and I was stupid,
the second time the water was about a foot deep and
I took my eyes off the road for a moment to turn on
the radio, (that's then I left Volvo for a while).

Needless to say, Volvo changed the design on later
models.

Try to get all that water out and as the previous
poster said, keep an eye on the head gasket, that
baby has been throught the wars now.

Best of luck,

Randy Anderson