Emission controls - engine breathing 1959-69

Open Crankcase Ventilation
1959-69
Open crankcase ventilation involved a pipe venting to atmosphere from the left hand tappet chest cover (of which there were several designs, only some of which are listed here, ending up with a compact, swan-necked pipe type), plus a hose running from the rocker cover to the air filter. Open crankcase ventilation was replaced in 1964 by positive crankcase ventilation in all but a very small number of Cooper and Cooper S models. However, the vast majority of single carburetter standard tune Minis built between 1964 and 1969 retained open crankcase ventilation.

848cc, 1959-64
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
1	37H3718	HOSE, rocker cover to air cleaner	1	Sold per metre.
2	ACA5290	CLIP, hose	2
3	12H948	COVER, tappet chest, LH, with early elbow pipe	1	Convex type cover.
4	12G280	COVER, tappet chest, LH, with late swan-neck pipe	1	Convex type cover.
5	12A1171	COVER, tappet chest, LH, with late elbow pipe	1	Concave type cover.
6	12A1139	GASKET, cover, cork	1	For convex type cover.
7	BH605151	BOLT, cover to block	1	For convex type cover.
8	2K4458	WASHER, bolt	1	For convex type cover.
9	GUG705505GM	GASKET, cover, rubber	1	For concave type cover.
10	SH605091	SCREW, cover to block	1	For concave type cover.
11	12A1177	WASHER, cup	1	For concave type cover.
12	12A1176	BUSH, rubber	1	For concave type cover.
13	MRC1980A	BUSH, rubber	1	Later design; replaces 12A1176 and 12A1177.

997cc, 998cc, 1071cc, 1275cc, 970cc, 1961-64
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
14	37H3718	HOSE, rocker cover to air cleaner	1	Sold per metre.
15	ACA5290	CLIP, hose	2
16	12H950	COVER, tappet chest, LH, with short elbow pipe	1	997cc; convex type cover.
17	12G280	COVER, tappet chest, LH, with late swan-neck pipe	1	Not 997cc; convex type cover.
18	12A1382	COVER, tappet chest, LH, with elbow pipe	1	Not 997cc; concave type cover.
19	12A396	PIPE, vent	1	997cc.
20	12G154	PIPE, vent	1	Not 997cc.
21	12A1139	GASKET, cover, cork	1	For convex type cover.
22	BH605151	BOLT, cover to block	1	For convex type cover.
23	2K4458	WASHER, bolt	1	For convex type cover.
24	GUG705505GM	GASKET, cover, rubber	1	For concave type cover.
25	SH605091	SCREW, cover to block	1	For concave type cover.
26	12A1177	WASHER, cup	1	For concave type cover.
27	12A1176	BUSH, rubber	1	For concave type cover.
28	MRC1980A	BUSH, rubber	1	Later design; replaces 12A1176 and 12A1177.
29	FNZ105	NUT, pipe and fuel pump blanking plate to block	1
30	LWZ205	WASHER, locking	1
31	PWZ105	WASHER, plain	1

All Engine Sizes, 1964-69
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
32	37H3718	HOSE, rocker cover to air cleaner	1	Sold per metre.
33	ACA5290	CLIP, hose	2
34	12A1382	COVER, tappet chest, LH, with elbow pipe	1	May be used on earlier models so long as correct gasket and fixings are also used.
35	12G154	PIPE, vent	1
36	GUG705505GM	GASKET, cover, rubber	1
37	SH605091	SCREW, cover to block	1
38	12A1177	WASHER, cup	1
39	12A1176	BUSH, rubber	1
40	MRC1980A	BUSH, rubber	1	Later design; replaces 12A1176 and 12A1177.
41	FNZ105	NUT, pipe and fuel pump blanking plate to block	1
42	LWZ205	WASHER, locking	1
43	PWZ105	WASHER, plain	1

Positive Crankcase Ventilation
1964-69
Positive crankcase ventilation (PCV) was fitted on relatively few standard tune, single carburetter Minis between 1964 and 1969 - in fact, probably only those destined for emissions-conscious export markets. By contrast, virtually all of the 1964-69 twin carburetter Cooper and Cooper S models were PCV fitted.

The PCV system is easily recognised by the mushroom shaped PCV valve positioned above and attached to the inlet manifold. The system was also known in some factory publications as closed circuit engine breathing. Instead of venting to atmosphere as in open crankcase ventilation, the fumes passed from the tappet chest cover through an oil separator (trap) and then via the PCV valve into the inlet manifold. The rocker cover to air filter hose of open crankcase breathing was not used on PCV fitted models.
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
44	13H5191	VALVE ASSEMBLY, PCV	1
45	27H7760	CLIP, cover	1	Included in valve assembly.
46	27H7756	SPRING	1	Included in valve assembly.
47	517582	SERVICE KIT, valve	1	Included in valve assembly.
48	149342	PLUNGER	1	Included in service kit.
49	27H7758	DIAPHRAGM	1	Included in service kit.
50	27H7759	COVER	1	Included in service kit.
51	SH604061	SCREW, valve to bracket	1
52	FNZ104	NUT	1
53	LWZ204	WASHER, locking	1
54	12H1405	ADAPTOR, manifold	1
55	1B3664	WASHER, sealing	1
56	12G577	COVER, tappet chest, LH, with oil separator	1	Convex type cover.
57	12A1212	COVER, tappet chest, LH, with oil separator	1	Concave type cover.
58	12A1139	GASKET, cover, cork	1	For convex type cover.
59	BH605151	BOLT, cover to block	1	For convex type cover.
60	2K4458	WASHER, bolt	1	For convex type cover.
61	GUG705505GM	GASKET, cover, rubber	1	For concave type cover.
62	SH605091	SCREW, cover to block	1	For concave type cover.
63	12A1177	WASHER, cup	1	For concave type cover.
64	12A1176	BUSH, rubber	1	For concave type cover.
65	MRC1980A	BUSH, rubber	1	Later design; replaces 12A1176 and 12A1177.

Manual Gearbox
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
66	12G609	BRACKET, valve to manifold	1
67	CHS2409	STUD, bracket to manifold	1	Early models.
68	FNZ104	NUT	1	Early models.
69	LWZ204	WASHER, locking	1	Early models.
70	SH504051	SCREW, bracket to manifold	1	Later models.
71	LWZ204	WASHER, locking	1	Later models.
72	12H1407	HOSE, valve to manifold	1
73	12A1052	HOSE, oil separator to valve	1
74	GHC507	CLIP, hose	4

Automatic Gearbox
Ill. No.	Part No.	Description	Qty. Rqd.	Remarks
75	12G1223	BRACKET, valve to thermostat housing	1
76	FNZ105	NUT, bracket to thermostat housing	1
77	LWZ205	WASHER, locking	1
78	12A1345	HOSE, valve to manifold	1
79	12G610	HOSE, oil separator to valve	1
80	GHC507	CLIP, hose	4

Items 37 to 43 of 43 total

Part No: GHC507

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CLIP-HOSE-WORM DRIVE 3/4'' (16-22mm)

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Part No: PWZ105

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WASHER - PLAIN - 5/16"

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£0.29 inc VAT £0.24 exc VAT

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Part No: FNZ105

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NUT - 5/16" UNF

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Part No: FNZ104

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NUT - 1/4" UNF

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Part No: LWZ205

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WASHER-SPRING, 5/16''

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Part No: SH604061

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SET SCREW-1/4'' UNF x 3/4''

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Part No: LWZ204

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WASHER-SPRING, 1/4''

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Items 37 to 43 of 43 total

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