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Cylinder bore dimension measurements for a Bentley '7' Unit after 57,000 miles of running.


Identifier  ExFiles\Box 144\3\  scan0043
Date  4th December 1935
  
TITLE: BENTLEY '7' UNIT - AFTER 57,000 MILES RUNNING - CYLINDER BORE DIMENSIONS

DETAILS:
CYLINDER BLOCK:- E.B. 89. - MATL Y/e
DRG: SIZE BORE: 3.250+.1.
NOTE: DIMS. 'AA {D. Abbot Anderson} ' TAKEN AT RT ANGLES TO C'SHAFT. DIMS. 'BB' TAKEN PARALLEL TO C'SHAFT.
Diagram Labels: CROWN, CENTRE, MOUTH
Diagram Dimensions: 3.80", .5"

TABLE DATA:

Cylinder 1:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.2515, BB=3.2505, Ovality=.001, Wear=NIL. AV=3.251.
- Centre: AA {D. Abbot Anderson} =3.252, BB=3.2525, Ovality=.0005, Wear=.00075. AV=3.2515.
- Crown: AA {D. Abbot Anderson} =3.2535, BB=3.2535, Ovality=NIL., Wear=.0025. AV=3.251.

Cylinder 2:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.25175, BB=3.25025, Ovality=.0015, Wear=.001. AV=3.250.
- Centre: AA {D. Abbot Anderson} =3.252, BB=3.253, Ovality=.001, Wear=.002. AV=3.2505.
- Crown: AA {D. Abbot Anderson} =3.2535, BB=3.2535, Ovality=NIL., Wear=.0035. AV=3.250.

Cylinder 3:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.25175, BB=3.250, Ovality=.00175, Wear=.00087. AV=3.250.
- Centre: AA {D. Abbot Anderson} =3.2515, BB=3.25275, Ovality=.00125, Wear=.00162. AV=3.2505.
- Crown: AA {D. Abbot Anderson} =3.25325, BB=3.25375, Ovality=.0005, Wear=.0035. AV=3.250.

Cylinder 4:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.2515, BB=3.250, Ovality=.0015, Wear=.00075. AV=3.250.
- Centre: AA {D. Abbot Anderson} =3.251, BB=3.2525, Ovality=.0015, Wear=.00125. AV=3.2505.
- Crown: AA {D. Abbot Anderson} =3.2525, BB=3.25375, Ovality=.00125, Wear=.00312. AV=3.250.

Cylinder 5:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.2515, BB=3.250, Ovality=.0015, Wear=.00075. AV=3.250.
- Centre: AA {D. Abbot Anderson} =3.251, BB=3.25225, Ovality=.00125, Wear=.00112. AV=3.2505.
- Crown: AA {D. Abbot Anderson} =3.2525, BB=3.2535, Ovality=.001., Wear=.003. AV=3.250.

Cylinder 6:
- Test: * *, NEW
- Mouth: AA {D. Abbot Anderson} =3.25125, BB=3.2505, Ovality=.00075, Wear=.00082. AV=3.250.
- Centre: AA {D. Abbot Anderson} =3.2515, BB=3.2525, Ovality=.001, Wear=.0015. AV=3.2505.
- Crown: AA {D. Abbot Anderson} =3.253, BB=3.254, Ovality=.001, Wear=.0035. AV=3.250.
  
  
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).


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