My 1970 westy with the 79 2.0L in it had been sitting most of the winter.
When I fired it up ,the lifters sounded like a tin can full of bolts. I
pulled both of the lifters from #2 and found that they were totally dry. I
pulled them apart and bled them and then put everything back together. #2
sounded great but the rest were still dry. So I used a trick that I have had
good luck with in the past, 2 Quarts of cheap 5W30 and 1 quart Rislone. Fired
it up, let it idle until warm, shut down, drain, change filter ( Always add
oil to the filter), fill with good quality 20w50 and drive. No more noise.
The thinner oil has always seemed to purge the air from the lifters faster
then the 20w50 does. And the Rislone/5W30 really flushes everything out.
                                                         Jeff Klender