Hillman Imp Buying Guide
Popular wisdom says you’d have to be mad to touch the diminutive Imp – but in reality nothing could be further from the truth. Here’s how to find a good one
How much to pay
• Project £1000-2500 • Good £3000-6500 • Concours £7000-10,000 •
Running costs ★★★★
DIY friendly ★★★★
If you listen to the bar-room pundits, you’d never go anywhere near a Hillman Imp. They’ll tell you about its shockingly bad reliability and terrible dynamics because of its rear-mounted engine. But we’d urge you to give the Imp the benefit of the doubt, because this car can genuinely give the Mini a run for its money.
With its slick gearchange, sharp steering, excellent handling, rev-happy engine plus low purchase and running costs, along with seating for four, the Imp (and a multitude of derivatives such as the Chamois and Stiletto) are far more deserving of your attention than many more high-profile classics.
The Imp’s reputation stems from it being launched before it was ready, way back in 1963. Poorly developed and even more badly built, early Imps were dogged by problems, most of which were fixed by the time the Imp Mk2 went on sale in 1965. Rootes had hoped to build 150,000 examples each year, but in a 13-year production run only 440,000 cars were made. Most of those have now disappeared – but if you fancy some fun on a budget, you know where to look.
Your AutoClassics Hillman Imp inspection checklist
The all-aluminium engine has a reputation for fragility that’s not entirely deserved. The key is to maintain anti-freeze concentration; if not, internal corrosion is guaranteed, leading to the coolant passages becoming clogged with debris that leads to overheating. Check the coolant level and look for signs of overheating, along with a failed head gasket.
Once an engine has overheated, the block can warp as well as the head. From 1966 a stronger block was used that’s less likely to deform; these later castings have a straight-edged top, while earlier units got a ‘curly’ edge. Only so much skimming is possible before the engine has to be scrapped. If the head has been skimmed too much, there will be pinking under acceleration; at this point a replacement head will be needed.
Blue exhaust smoke betrays worn valve seals when starting from cold; it’s an easy and cheap DIY repair. The Imp Sport had no valve seals but it does have guides that wear; again, they’re not costly to fix.
When cruising, the temperature gauge should sit somewhere around the half-way mark. If the engine struggles to get warm, the thermostat has probably been removed to mask an overheating problem. Water pumps normally last no more than 25,000 miles, and they can fail a lot sooner than this on Imps used only sparingly, adding to the likelihood of overheating.
Oil leaks are normal, largely because aluminium expands more than cast iron. Any weeping is to be expected – but if it’s more significant than this, the engine will probably have to come apart for fresh gaskets to be fitted.
All Imps have an all-synchro four-speed manual transmission, which should have a slick change. If it doesn’t, it’s because fresh nylon bushes are required at the base of the gearstick; they’re cheap to buy and easy to fit. Baulky shifts point to tired synchromesh, but exchange gearboxes are available readily enough.
Clutches last well, as the Imp’s engines aren’t especially torquey, but the hydraulic system can suffer from hoses that have collapsed internally, leading to a heavy pedal. Replacement is cheap and easy, though.
The driveshafts are fitted with a rubber rotoflex coupling, and these perish; a visual check will show if replacements are due. Cheap items don’t last long, so use heavy-duty parts that should last for years.
Suspension and brakes
If the rack-and-pinion steering isn’t light and sharp, the kingpins have worn and need to be replaced. It’s easy to fix on a DIY basis, as are worn rear wheelbearings, which are common. Neither is an expensive job.
All Imps and associated derivatives came with drum brakes front and rear, which provide ample stopping power. The Sunbeam Stiletto and Imp Sport got a servo plus a bigger master cylinder, but there were still no discs. The only likely problem with the braking system is wheel cylinders not returning because of a blocked ventilation hole in the reservoir cap. It’s easily sorted with a pin.
An Imp bodyshell is strong, but poor rustproofing means corrosion is likely – and potentially a lot of it. Any part of an Imp can rust, so look everywhere, focusing initially on the obvious places: wheelarches, sills, valances, door bottoms and the leading edge of the double-skinned bonnet, which rots from the inside out.
Also expect corrosion in the trailing edges of the front wings, the floorpans and the rear-spring mounting points. Corrosion is common in the pans that locate the rear springs, too, as well as the box-section swing axles. The latter can’t be repaired and new ones aren’t available, so decent used items are your only option.
You need to make sure all of the interior and exterior trim is present and correct, because finding replacement parts can be a nightmare. You won’t find anything new, and some used parts are very scarce.
Moulded seats were fitted from the 1968 Mk3, so repairs are tricky, but earlier cars are easy (but probably costly) to retrim if necessary. The mazak badges can’t be restored, but most of the other brightwork is made of stainless steel or anodised aluminium, so it tends to last pretty well.
The electrics are simple and reliable, although age can take its toll on the wiring and connections as well as the earths. The switchgear for pre-1968 Imps is hard to find, but later parts are more readily available.
- 1963: Hillman Imp launched with basic or Deluxe trim.
- 1964: Singer Chamois arrives.
- 1965: Imp Super on sale, and Imp Mk2, now available as Super and Deluxe only. Limited-edition Rallye Imp and Rallye Chamois released, along with Commer Imp van.
- 1966: Singer Chamois Sport and Sunbeam Imp Sport appear, with 52bhp.
- 1967: Imp Californian, Chamois coupé, Stiletto coupé and Husky (estate) arrive. The first three have fastback styling and four headlamps.
- 1968: Mk3 Imp appears, with new instruments and improved trim.
- 1969: Chamois and Sunbeam Imp Sport get quad headlamps. New entry-level edition reintroduced.
- 1970: Hillman drops Imp Californian, van and Husky, while Singer discontinues Chamois. Sunbeam Imp Sport renamed Sunbeam Sport.
- 1973: Basic Imp dropped once more.
- 1975: Imp Caledonian special edition launched, with red paint and white side stripes.
- 1976: Last Imp produced.
While Imp values have risen recently, these cars have been worth so little for so long that many examples have been run for years on a shoestring. As a result, it can be hard to find a truly superb car; the best ones tend to be retained by doting owners.
So, as with any classic, your task is to sort the wheat from the chaff – which means taking any potential purchase for a long test drive and getting an independent inspection if necessary. Sympathetically modified examples are worth seeking out – indeed, a car that’s completely standard is likely to be less usable than one that’s had improvements made to the cooling and braking systems.
The sportier editions (the Sunbeam Stiletto and Imp Californian) are predictably the ones that most buyers want, along with the ultra-rare vans and estates. However, any Imp in good condition will be a joy to drive as well as to own.
|Hillman Rallye Imp|
|Sunbeam Imp Sport|
Image courtesy of MagicCarPics
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