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).
Engine condition, front axle, and a comprehensive analysis of front spring leaf failures.
| Identifier | WestWitteringFiles\M\2April1925-June1925\ Scan73 | |
| Date | 1st May 1925 | |
| R.R. 493A (50m) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. -2- Expl. No. REF: GWM/Cms. 5. 25. There is a fair amount of carbon deposit on piston heads. Engine generally is clean and free from oil leaks. Tappet settings have kept even. No.1. still noisy at bottom of push rod end. Heat from scuttle and floorboards as per my previous report. Exhaust boxes - these are O.K. Induction pipe has not been taken off for examination, but from outside appearance it seems to be quite O.K. FRONT AXLE. Pivots and bearings O.K. Brake operating shafts with larger bearings - there is now slight wear noticeable. Pull rods operating front brakes - these should have more adjustment for ball ends. We have got slack in these, which cannot be taken up without altering the design. FRONT SPRINGS. Both springs have now been taken off the car. N.S.F. spring taken off after 11,485 miles. O.S.F. 12,235 The following chart shews the condition of these springs :- Leaves. | Condition. | Where cracked. | Approx. length of crack. 1 | O.K. | | 2 | Cracked. | Near rear sprg.clip from inside. | 3/4" 3 | Cracked. | * * * outside. | 3/4" 4 | O.K. | This appears to be on soft side. | 5 | Cracked. | Near rear sprg.clip from inside. | 3/4" 6 | Cracked. | * rear of centre bolt - outside. | 3/4" 7 | Cracked. | * rear of centre bolt - inside. | 3/4" 8 | Cracked. | * * * * | Half way across. 9 | Broken | * rear of centre bolt. | 10 | Cracked. | 1+" rear of centre bolt - inside. | 3/4" 11 | Cracked. | 1+" * * * * | 3/4" | ||