Rolls-Royce 20/25/30 HP
Coolant capacity & service interval
The Rolls-Royce 20/25/30 HP uses coolant with a capacity of 17.05 liters. The data covers 4 configurations of this model.
The configuration chart below lists fill volumes and service intervals for each engine and trim variant.
| Type | Specifications |
|---|---|
| 25/30 HP (1936-1938) |
|
| 20/25 HP, GKC1-22 -> (1934-1937) |
|
| 20/25 HP, <- GKC1-22 (1929-1934) |
|
| 20HP (1922-1925) |
|
Additional Notes
- The Rolls-Royce 20/25/30 HP cooling system capacity is recorded at 17.05 liters across all listed configurations, a figure that represents the total volume of the entire cooling circuit rather than a partial or top-up quantity.
- The 20 HP variant, covering 1922-1925, shares the same 17.05-liter cooling system capacity as the later 20/25 HP and 25/30 HP variants, indicating a consistent cooling circuit volume across the model family's production span.
- The 20/25 HP is split into two distinct chassis ranges: pre-GKC1-22 covering 1929-1934, and GKC1-22 onward covering 1934-1937. Both carry the identical 17.05-liter capacity, meaning the chassis sequence change did not alter the cooling system volume.
- All four configurations are designated under normal use conditions, meaning the 17.05-liter capacity figure applies to standard operating environments rather than severe-duty or first-change scenarios.
- The 25/30 HP, spanning 1936-1938, maintains the 17.05-liter cooling system capacity, placing it in alignment with the earlier 20 HP from 1922-1925 despite representing a later and more developed stage of the model line.