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).
Strip examination report of Engine Unit No.5 after a 20,000 mile road test in France.
| Identifier | ExFiles\Box 91\4\ scan0271 | |
| Date | 25th September 1935 guessed | |
| SPECTRECodename for Phantom III 3-S-1. STRIP EXAMINATION AFTER 20,000 MILES ROAD TEST IN FRANCE. ENGINE UNIT No.5. Crankcase & Bearings. The top half crankcase is in good condition but the lower half is cracked in the rear end wall of the sump as shown by the sketch appended. The main bearings are in poor condition, white metal having broken away in various places. There is also evidence of fretting on the backs of the shells: see attached photographs. On the oil gallery pipe the solder has cracked at several branch connections and also at No.5 main joint. Crankshaft - V.C.M. Balanced type. E.86165 Slight pitting is noticeable on all pins and journals and the latter are worn to the extent of .001. Fretting has taken place on the flange face and spigot. Journal oil caps are damaged due to fouling of split pin heads in forked connecting rod bolts. Connecting Rods - (Bearings RR.BZ/L. E.86161/2) Excessive wear has taken place in bores and outer bearing surfaces of all big ends. The average wear is .010" on each diameter. a chart is attached showing actual dimensions before and after test. Forked and plain rods themselves are in good general condition. The forked rods are fretted in the bearing housings, whilst the bore of the plain shows .00125 wear on diameter. Cylinder Heads. Off-Side Head - Pocketting and pitting is noticeable on all inlet inserts although this is only of a minor character. Damage has been sustained to crown of No. 5 bore owing to the exhaust valve failure which took place during the course of the test. Incidently this necessitated the fitting of a new exhaust insert, the material of which is BZ/A, the original seating being in N.M.C. material. Wear to the extent of .003" occurs in Nos. 2,3,9 & 11 valve guide bores. All sparking plug threads on exhaust side are easy fit to gauge. Near-Side Head - Inlet inserts are pitted and slightly pocketted as in the offside head. Several valve guides are worn in bore, the outstanding examples being in No.3 (.006" wear - rejected) and Nos. 10 and 11, (.002 wear) material being I/C 212A. A small crack due to local porosity has developed at Nos. 2 and 6 tappet plunger case facings. continued | ||