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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).
Cold starting issues with the Phantom III starting mechanism, specifically automatic tappets and gear ratios.

Identifier  ExFiles\Box 151\3\  scan0348
Date  17th December 1937
  
[Handwritten top right]
1290 BY.21/G.17.12.37.

[Typed header]
Rm. {William Robotham - Chief Engineer}
C. Da. {Bernard Day - Chassis Design}
C. Mx. {John H Maddocks - Chief Proving Officer} (crossed out)
C. Hs. {Lord Ernest Hives - Chair} (crossed out)
----------

[Handwritten top left]
Mx {John H Maddocks - Chief Proving Officer}

[Handwritten across top]
Did this car run consistently after starting
Pin

[Typed title]
PHANTOM III - STARTING MECHANISM.

[Typed body]
The information given as a result of cold starting condition test in cold chamber reported under cover of Rm. {William Robotham - Chief Engineer} 3/R.11.12.37. as you point out indicates clearly two things :-

(1). That the automatic adjusting tappet is a serious debit under conditions below freezing point as compared with fixed adjustment.

(2). That we could with advantage have a lower ratio of gearing with advantage from increased ease of starting.

In regard to Item 1. we have not had any complaints under this heading in this country, although cars have been purposely left out to check this point, and in the case of Mrs.Tudor Hart's car the temperature was well below freezing, but it started without trouble.

In regard to Item 2. until we can find a way of using the 25/30 and Bentley scheme we dare not run the risk of increasing the speed of the motor under false engine start conditions. The 25/30 scheme will not fit in without serious modification so far as one can see at present. The pinion end fouling the cross in the main frame.

[Handwritten bottom]
Rem.
This was based on a statement of mine referring to starter motor efficiency only.
The engine ran very erratically in fact we had to "bleed" several tappets.
PIII engines with hydraulic tappet mechanism are notoriously bad for starting & running regularly under cold conditions. BY. {R.W. Bailey - Chief Engineer}
RP
By
  
  


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