I joined the BA747-100/200 fleet in 1987. The aged Captains, and FE's would delight in telling the -3 stories.
One I remember is that at top of descent the FE would be tasked with closing the thrust levers. This was done at a practised and special rate. Too fast or slow, and all four engines would flame out.
Another temporary solution to this problem was the metal bar. It was inserted across the thrust lever quadrant so that the levers could not be fully closed. When it went on and off I am unable to recall.
The -7s that were on the wing when I flew them seemed to burn more oil than fuel.. I remember range was limited by oil consumption!
In round numbers the P&W used 12 tons an hour. The Roller 11 tons an hour.