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).
Issues with throttle springs and linkages on S.U. Carburetters.
| Identifier | ExFiles\Box 107\2\ scan0014 | |
| Date | 5th April 1939 | |
| Rm.{William Robotham - Chief Engineer} c.c. BY.{R.W. Bailey - Chief Engineer} c.c. De. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux}34/G.5.4.39. THROTTLE SPRING - S.U.CARBURETTERS. With reference to your memo Rm.{William Robotham - Chief Engineer}1/MH.{M. Huckerby}31.3.39. the Depot at K.{Mr Kilner} have on an average as many complaints of throttle sticking (i.e. not fully coming on the stop) with the lower stressed spring EB.3429 as with other types. The springs when pulled out take up a permanent set, approximately .125" to .185" longer. This leaves very little tension of the spring in the closed throttle position. Springs I had made at the Works did not suffer from this weakness, and the half dozen fitted have not been seen or heard of since. Taking a link from the above arrangement gives sufficient tension to the spring to overcome the trouble, and stay put for a lengthy period. The chief trouble with our throttles is that the design of link up is too complicated, and snags are met with from the accelerator pedal to the throttle. For instance, when wear takes place in the counter shaft bearing located at the bottom side of the engine, the slackness affects the operation of the link rods and sticking ensues. Tightness of the accelerator bearing still exists, distortion of the throttle barrels through overtightening is still a trouble, throttle spindles themselves are found tight in the bearings. One has to go through the whole of the link system to make sure of curing the last little bit of throttle closing. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} | ||