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).
Procedure for addressing booming issues by replacing friction discs in the torque reaction dampers on a 20/25 HP model.
| Identifier | ExFiles\Box 104\1\ scan0096 | |
| Date | 21th November 1930 | |
| (5005 To Hd.{Mr Hayward/Mr Huddy} For Depot Sheet. From Hs{Lord Ernest Hives - Chair}/AJL. Hs{Lord Ernest Hives - Chair}/AJL. 2/MJ. 21.11.30. TORQUE REACTION DAMPERS. 20/25 HP. In cases of complaint of a period of booming (on forward or on over-run) at 48 M.P.H. to 52 M.P.H. the following procedure should be adopted. Replace the Ferodo friction discs of the torque reaction dampers by cotton "A" fabrics. These should be soaked in engine oil (Motorine "C") for twleve hours before being fitted. The spring tension should be adjusted to give a load of eight pounds (measured by spring balance or weights in the usual manner). When setting the load it is important to obtain the same conditions that occur on the car, a distance piece 'A' should be used and the two arms of the damper bolted up to it before setting the load. The thickness of the distance piece must be equal to the thickness of the lug on the crankcase to which this portion of the damper is attached. The bolt 'B' must also be tight. When erecting the dampers on the car it is very important that the bolts on the engine be tightened up first; the bolts holding the dampers to the frame must not be tightened up at all until the engine has been run sufficiently for it to attain its normal running temperature. Hs{Lord Ernest Hives - Chair}/AJL. Print attached. | ||