OVERHAULING YOUR ROLLS-ROYCE OR BENTLEY ENGINE: MAIN BEARINGS & BIG END BEARINGS
We now stock our own Prestige Parts℗ main bearings (from RH2082-X to RH2093-X) and big end bearings (from RE3236SA-X to RE15121SA-X) for the straight 6 engine present in Rolls-Royce Silver Wraith, Silver Dawn & Silver Cloud I models as well as Bentley Mk VI, R-Type & S1. So if you were thinking of bringing your old Rolls-Royce or Bentley engine back to its full glory by overhauling it then you should definitely look into replacing all the bearings within.
Engine bearings and connecting rods support the crankshaft, allowing it to spin freely inside the engine bay. The rotation of the crankshaft is crucially important to the operation of your vehicle. It is exactly what makes your car move, and the engine bearings provide the support for that to happen. We have three different sizes for all main bearings whether you have a 4.25 Litre, 4.5 Litre or 4.9 Litre engine, going from the standard size to -0.020". If you are rebuilding your Rolls-Royce & Bentley engine back to former glory it is worth changing the bearings which might mean having to grind your crankshaft down to an smaller size in order to create a new smooth surface. In this table you can find the different stages of grinding for the crankshaft.
Crankshaft grinding stages
| Stages of regrinding | Diameter of Journals | Diameter of crank-pins |
|
1 3 4 |
2.740 2.730 2.720 2.710 |
1.989 1.979 1.969 1.959 |
Big end bearings connect the crankshaft to the pistons and are necessary for the proper functioning of an internal combustion engine. We have three big end bearings available in stock that work for all three engine sizes: RE3236SA-X (standard), RE9906NF-X (-0.010") and RE15121SA-X (-0.020"). In the next table below you can find the dimensions of the bore and journals for each of the engine sizes.
| Engine Size | 4 ¼ Litre | 4.5 Litre | 4.9 litre |
|---|---|---|---|
| Crankshaft main journals | 2.750” (standard) | 2.750” (standard) | 2.7495 - 2.750” (standard) |
| Crankshaft big end journals | 1.999” (standard) | 1.999” (standard) | 1.9985 - 1.999” (standard) |
| Cylinder Bore | 3.500” | 3.625” | 3.750” |
| Stroke | 4.500” | 4.500” | 4.500” |
| Cubic Capacity | 260 cu.ins (4257cc) | 279 cu.ins (4566cc) | 298 cu.ins (4887cc) |
| Oil capacity | 16 pints (9.1 litres) | 16 pints (9.1 litres) | 16 pints (9.1 litres) |
Given that they are one of the essential components of a car, they are subject to much wear and tear and often need replacing, but there is a difference in the seriousness of faulty engine bearings. If your main bearings go then the crankshaft will likely need replacing, but if your rod bearings go the engine itself might need to be rebuilt altogether. It is advised that you consult a specialist mechanic to ensure that you have the correct diagnosis for your car. Below is a table with all the bearings available for all three different size engines.
[table id=22 /]
Check the RR - Technical Video Library for more.
Check the RR - Technical Video Library for more.
