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).
Chassis clearance and front hydraulic damper issues for the Paris Trials Car.
| Identifier | ExFiles\Box 146\5\ scan0320 | |
| Date | 12th April 1940 | |
| Handwritten notes at top: Ak E.J.H. } Please note & let me have your comments To Sr. F.Doelal } 12.40 Rm{William Robotham - Chief Engineer} FILE Typed Document: Levallois Sr/VA3/ET.12.4.40 Re: CHASSIS WIZ.AW - PARIS TRIALS CAR ------------------------------- 1. CLEARANCES AT FRONT OF CHASSIS After the fitting of the body, we found there was insufficient clearance at the following points: Jaws of the o/s and n/s pull rods (inner end) to front brake mechanism fouled the side plates as fixed to the dashboard and radiator shell for the attachment of the bonnet side plates. We filed the side plates to give more working clearance. We also fitted a ferodo packing about 1/4" thick to each of the rubber blocks of the radiator mounting (suspension), so as further to increase the clearance at the above mentioned point. There was also insufficient clearance between the side plate surrounding the top of the front hydraulic dampers. Gave necessary working clearance by filing the side plate as necessary. The above will have to be corrected on future production. I understand that you have already sent Rm.{William Robotham - Chief Engineer} a sketch and details re the two other points where fouling took place. 2. FRONT HYDRAULIC DAMPERS Handwritten Initials: Clm{D. D. Clapham} Car found to crash, especially at the n/s front. There was also a very bad groan which came from the front of the car, as if a bush had started or had seized (this noise could not be produced in the shop by rolling or bouncing the car). The noise was very pronounced when the car was driven over fairly bad roads and could be heard, but to a lesser degree, when the car was driven over a wavy road. It appeared to come from the o/s front damper, but was very difficult to locate. Removed the front dampers and checked the poundage as follows: Attached a 20 Kgr. weight to the end of the main levers of the o/s damper. It took 20 seconds for the lever to complete the full downward stroke, and only 3 seconds for the n/s damper. There was scarcely any pressure on the upward stroke of the dampers. We dismantled the dampers and discovered the following: 1. Traces of "foreign matter" in dampers (fine metal dust). 2. Several high spots (not seized) on pistons, but otherwise O.K. 3. We noted that the bores (for pistons) in body of dampers are rough finished. Is there a reason for this? 4. One bore on the o/s damper is from .002" to .003" taper. 5. We also observed, on the o/s damper, that the small metal cap (see point 'A' on sketch attached) as fitted | ||