Torque Figures | Rolls-Royce Silver Spirit, Silver Spur & Bentley SZ Models

Tighten all setscrews, full nuts, and half nuts to the figures given in the tables below, except those components listed in the special torque tightening section within each Chapter of the Workshop Manual or on our website.

Setscrews should be tightened to the figures quoted for full or castellated nuts.
Plated parts should have all burrs and foreign matter (e.g. grit, grease, and paint) removed from mating faces of the nuts, setscrews, washers and components to ensure that the correct torque tightening figures are obtained.

The threads and mating faces of non-plated parts should be smeared with engine oil before being fitted.

All unified nuts having an identification groove on one end, are to be fitted with the groove end away from the mating face.

Certain items should not be torque tightened and these are as follows.
1. Nuts which are locked by riveting
2. Wood screws
3. Hub assembly retaining nuts (front and rear)
4. All threads less than 2 B.A. (except items listed in the special torque tightening sections)

Components used during manufacture of the vehicle may have different thread formations (Metric UNF, UNC, etc). Therefore, when fitting nuts, bolts, setscrews it is important to ensure that the correct type and size of thread formation is used.

This information can be found in TSD4400 Workshop Manual in Section P1

 

Half Nut (Imperial)

Size	Nm	kgf m	Ibf ft
2 B.A	3-4	0,3-0,4	30-36 lbf in
1/4 in UNF	7-9	0,7-0,9	5-7
5/16 in UNF	18-20	1,8-2,0	13-15
3/8 in UNF	30-34	3,0-3,4	22-25
7/16 in UNF	45-49	4,6-4,9	33-36
1/2 in UNF	65-71	6,7-7,2	48-52
5/8 in UNF	99-106	10,1-10,8	73-78

Full Nut (Imperial)

Size	Nm	kgf m	Ibf ft
2 B.A	5-7	0,5-0,7	48-60 lbf in
1/4 in UNF	11-14	1,2-1,4	8-10
5/16 in UNF	21-24	2,2-2,4	16-18
3/8 in UNF	39-43	4,0-4,4	29-32
7/16 in UNF	57-61	5,8-6,2	42-45
1/2 in UNF	81-88	8,3-8,9	60-65
5/8 in UNF	115-122	11,7-12,4	85-90

Full Nut (Metric)

Size	Nm	kgf m	Ibf ft
M6	11-14	1,2-1,4	8-10
M8	27-30	2,8-3,0	20-22
M10	55-60	5,7-6,1	41-44
M12	95-100	9,7-10,2	70-74
M16	240-250	24,5-25,5	177-184