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Imp Mk II

September 1965 - October 1968

The number of small design changes became so large that it was decided that the Imp ought to be reintroduced in September 1965.
Mechanically there were major changes, some were new, some had been used over the past few months without making it an issue to the public.

These Mark IIs were fine cars. They were reliable and quiet. But dealers and customers had lost faith.

Changes

A water pump.
The cylinder head, with larger ports and valves, both inlet and exhaust (no perfomance benefit, compared to a good Mk I, but the casting was easier). Inlets were 0.138in larger and exhausts 0.054in bigger in diameter.
A larger and heavier clutch which lasted longer.
A modified acceleration pedal for smoother control
Leathercloth covering of the parcel shelf
A pair of ashtrays for the rear compartment
A total of 33lb of underseal and more sound proofing.
'Mark II' emblems on the doors

early models	later models
teflon king pins	bronze bushes
automatic choke	manual choke
rust under the rear roof surround : a push-on strip covering a joint	strip and surround are dipped in a rust-proffing primer separately
trouble with the cooling system	new type cylinder-head gasket
	radiator acquired a blister to give more header tank expansion
fan with 9 blades	fan with 11 blades
	water pump seals were modified
pneumatic throttle	cable (although a modification removes any trouble from the pneumatic one)
plastic fuel pipe from pump to carburettor	synthetic rubber
exhaust pipe kicks up dust by pointing downwards	exhaust pipe comes almost straight back
engine cleanliness not optimal	an undertray above the silencer
scuttle shake on very rough roads	two 6in. struts behind the facia

Two of the Imp's revolutionary designs kicked the bucket.

The PTFE Teflon king-pin bushes went quietly.
If an Imp was left inactive for a while, water would enter the bearings and rust the king-pin, thus destroying the bearings. Also, oil would cause the teflon the swell, and that would make the steering terribly heavy. So traditional bronzes bushes were put in. And from then on the car had four grease nipples for the steering king-pins, and lost its claim of not needing any chassis lubrication at all.
The automatique choke disappeared (in fact late Mark 1 models already had a hand choke). The choke cable that was installed was lenghty, but it improved durability. The manual choke was not interchangeable with the original for which all spares were available.

The basic saloon was dropped from the range.

In 1967 all cars benefitted from a rearrangement of the front suspension to remove the excessive camber.
The only real changes in the chassis for the whole of the Imp production run came with the Mk 2. Basically the central pivot of the front suspension was lowered to correct the 'toe in' of the front wheels. New (longer) drop brackets and steering rack brackets were used.
There were changes to the spring weights but these were small changes and were standardised to part number 7102489 for the rear and 7102493 for the front from chassis number B.421000101 for a standard, B.4110011227 for a De-luxe, B492004212 for a Sport, B.792001843 for a Chamois Sport and B.301001116 for a Stiletto. I believe these chassis numbers correspond approximately to the introduction of Mk 2.

Mark 3

never badged as such

In October 1968 the Mk II designation was discontinued. The whole range of Imps was revised: all models (except the Stiletto) were given a new interior. They got new seats and upholstery and many variations of external trim. The new facia was full width with a round set of gauges including the speedometer.
This revision is sometimes referred to as the introduction of the Mk 3.

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Franka