Uploaded November 2017 | Updated September 2026, 2 hours ago
In recent years engine problems relating to noise from the tappet chest have increased dramatically.
We have carried out extensive research and our findings and recommendations are as follows.
Please contact us if you have any further questions.
The aftermarket tappets we supply were not originally manufactured for Rolls-Royce or Bentley motor
cars but by following our recommendations we believe that they are a suitable and acceptable substitute
for the original tappets.
These instructions are relevant, however, whether you are fitting aftermarket or OEM tappets.
Prior to following our recommendations and starting any work on your engine it is imperative that you
have read the relevant sections of the Workshop Manual – please contact us (sales@flyingspares.co.uk)
should you require a copy of the manual.
We believe that the key to avoiding noise from the tappet chest is obtaining the correct amount of
tappet lifter/ push rod preload.
Factors affecting the preload include:
A. Refacing of the cylinder heads and crankcase faces.
B. Wear on the inlet and exhaust rockers.
C. The lapping in of the valves and seats and the amount of wear on them.
D. Previous unknown standards of repair or associated problems affecting the tappets such as a worn camshaft, incorrect engine oil, low oil pressure, seized valves.
We recommend following the procedure below to ascertain how much preload there is on the fitted
push rods in your engine.
You will need the following items:
1. 3/8” large washer (large enough to cover the tappet hole in the tappet block)
2. Vernier caliper
3. White paint pen
4. Scribe
5. Short rocker tool (UE8767TOOL) which allows accurate measurement of the preload by offering greater control (than using the actual rocker shaft) when releasing the tension on the push rod.
In recent years engine problems relating to noise from the tappet chest have increased dramatically.
We have carried out extensive research and our findings and recommendations are as follows.
Please contact us if you have any further questions.
The aftermarket tappets we supply were not originally manufactured for Rolls-Royce or Bentley motor
cars but by following our recommendations we believe that they are a suitable and acceptable substitute
for the original tappets.
These instructions are relevant, however, whether you are fitting aftermarket or OEM tappets.
Prior to following our recommendations and starting any work on your engine it is imperative that you
have read the relevant sections of the Workshop Manual – please contact us (sales@flyingspares.co.uk)
should you require a copy of the manual.
We believe that the key to avoiding noise from the tappet chest is obtaining the correct amount of
tappet lifter/ push rod preload.
Factors affecting the preload include:
A. Refacing of the cylinder heads and crankcase faces.
B. Wear on the inlet and exhaust rockers.
C. The lapping in of the valves and seats and the amount of wear on them.
D. Previous unknown standards of repair or associated problems affecting the tappets such as a worn camshaft, incorrect engine oil, low oil pressure, seized valves.
We recommend following the procedure below to ascertain how much preload there is on the fitted
push rods in your engine.
You will need the following items:
1. 3/8” large washer (large enough to cover the tappet hole in the tappet block)
2. Vernier caliper
3. White paint pen
4. Scribe
5. Short rocker tool (UE8767TOOL) which allows accurate measurement of the preload by offering greater control (than using the actual rocker shaft) when releasing the tension on the push rod.
