Not P but Moby-Dick (42)

[Mike Jing]

>From Chapter 54:

“ ‘Aye, aye, my merry lads, it’s a lively leak this; hold a cannikin, one
of ye, and let’s have a taste. By the Lord, it’s worth bottling! I tell ye
what, men, old Rad’s investment must go for it! he had best cut away his
part of the hull and tow it home. The fact is, boys, that sword-fish only
began the job; he’s come back again with a gang of ship-carpenters,
saw-fish, and file-fish, and what not; and the whole posse of ’em are now
hard at work cutting and slashing at the bottom; making improvements, I
suppose. If old Rad were here now, I’d tell him to jump overboard and
scatter ’em. They’re playing the devil with his estate, I can tell him.

What does "old Rad’s investment must go for it" mean here?