I have Eleanor Kewley as bapt 11 Mar 1764 Lonan, d/o Patrick Kewley and Margaret Watterson but with my track record today, I wouldn't be surprised it's wrong.

I'm pretty sure this is her:
1851 census at 6 Water Lane, Douglas HO107/2525 246 pg 59 #254 (105992-6)
William SCARFF, Head Mar 55, Coal Porter, b Isle of Man Lonan
Ann SCARFF, Wife Mar 45, b Isle of Man Lonan
William SCARFF, Son U 25, Ostler, b Isle of Man Douglas
John SCARFF, Son 14, Messenger, b Isle of Man Douglas
Edward SCARFF, Son 8, Scholar, b Isle of Man Douglas
Eleanor SCARFF, Mother Widow 90, b Isle of Man Lonan

Burial: SCARFF, Eleanor 93 Lon 2 Apr 1853 (BL Web)
"From Douglas, buried at Lonan, aged 93".
No will on index

The following 1841 might be her or Eleanor Scarffe (nee Gelling, and a relative of mine) widow of Wm Scarff:

1841 census at Ballakilv martin, Onchan HO107/1465/2 4 14 pg 5 (464357)
William CLUCAS 25 Ag Lab Y
Jane CLUCAS 24 Y

Eleanor SCARFFE 70 Ind. Y
Mary Anne CHRISTIAN 6mos Y
[just a bit above at Bibalve is Jane SCARFFE 8 Y in QUIRK family]

That's about all I can contribute at the moment.