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Test report detailing valve dimensions and pocketting for a Bentley 80 No.1 unit after a 68-hour run.


Identifier  ExFiles\Box 124\1\  scan0024
Date  23th February 1939
  
UNIT NO BENTLEY 80. No.1
VALVE DIMENSIONS
PASSED TO TEST 9-12-38
COMPLETED TEST 23-2-39

INLET VALVES: โ€”
CYLINDER HEAD โ€”
EXHAUST VALVES: - EB.7378 (SOD.COOLED)
RUNNING TIME:- 68 HRS.
MILEAGE:- (18 HRS. 50 MINS F.T.)

Diagrams:
Valve with dimensions: LENGTH, 2.000, DIA. 'A', 1.350, DIA. 'B'
Cross-section of valve seats: "A", "B", "A", "B", POCKETTING

First Table:
EXHAUST
NO | LENGTH: BEFORE | AFTER | DIFFERENCE | DIA. 'A': BEFORE | AFTER | WEAR | DIA. 'B': BEFORE | AFTER | WEAR
1. | 4.9040 | 4.9030 | .0010 | .3718 | .3717 | .0001 | .3718 | .3712 | .0006
2. | 4.9100 | 4.9100 | NIL. | .3715 | .3715 | NIL. | .3715 | .3712 | .0003
3. | 4.9000 | 4.8970 | -.0030 | .3715 | .3715 | NIL. | .3715 | .3712 | .0003
4. | 4.8950 | 4.8920 | -.0030 | .3715 | .3715 | NIL. | .3718 | .3710 | .0002
5. | 4.9020 | 4.8990 | -.0030 | .3718 | .3715 | .0003 | .3718 | .3712 | .0006
6. | 4.8950 | 4.8945 | -.0010 | .3715 | .3715 | NIL. | .3715 | .3712 | .0003
7. | 4.8970 | 4.8960 | -.0010 | .3715 | .3715 | NIL. | .3715 | .3706 | .0009
8. | 4.8910 | 4.8890 | -.0020 | .3715 | .3712 | .0003 | .3715 | .3710 | .0005

EXHAUST
6
7
10
11

Second Table: POCKETTING
NO | DIM. 'A': BEFORE | AFTER | DIFFERENCE | DIM. 'B': BEFORE | AFTER | DIFFERENCE
INLET
1
4
5
8
9
12

EXHAUST
2
3
6
7
10
11
  
  
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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