Car Mechanics November 2021

Editorial DS3 dilemma Martyn Knowles, Editor Email martyn.knowles@kelsey.co.uk Follow us on Facebook @ Car Mechanics ► I had Rob Hawkins stay-over for a few nights while he dropped off the project Jaguar XF (he says he has finished with it); help do a clutch change article on my Toyota Corolla Verso; drive to Canterbury to photograph a Jaguar MkII before returning back to Leeds via BCA Blackbushe to help fetch our latest project car – a 2011 Citroën DS3 1.6 HDi. It was while we were eating in the evening that my British Car Auction app pinged up a notification that this Black and White model was about to be sold. I had seen the bodywork damage via pictures and its description, so was hoping to win this car for…

Email martyn.knowles@kelsey.co.uk Follow us on Facebook @ Car Mechanics ► I had Rob Hawkins stay-over for a few nights while he dropped off the project Jaguar XF (he says he has finished with it); help do a clutch change article on my Toyota Corolla Verso; drive to Canterbury to photograph a Jaguar MkII before returning back to Leeds via BCA Blackbushe to help fetch our latest project car – a 2011 Citroën DS3 1.6 HDi. It was while we were eating in the evening that my British Car Auction app pinged up a notification that this Black and White model was about to be sold. I had seen the bodywork damage via pictures and its description, so was hoping to win this car for much less than the CAP Clean of £2925. The…

While many people view the Continuously Variable Transmission (CVT) as a fairly recent development, its history is almost as long as that of the motorcar. In North America, H. C. Spaulding patented an infinitely variable gearbox in 1897, which utilised a drive belt and a pair of conical pulleys. By manipulating a series of levers, the driver could alter the gearing, by varying the belt’s position infinitely between the larger, or smaller, diameter portions on the pulley. The system found favour in industrial machinery and, while some sources acknowledge the intention for a motorcar application, no examples are known to have been made. Meanwhile, in France, Gustave Fouillaron used a pair of variable pulleys to power the vehicle that bore his name in 1901. Yet, the system still had to be…

INSTANT EXPERT CONTINUOUSLY VARIABLE TRANSMISSION Since starting life as a niche but straightforward oddity, the stepless automatic transmission has been adopted in a wide range of models but Rob Marshall finds that modern complication has not improved reliability. While many people view the Continuously Variable Transmission (CVT) as a fairly recent development, its history is almost as long as that of the motorcar. In North America, H. C. Spaulding patented an infinitely variable gearbox in 1897, which utilised a drive belt and a pair of conical pulleys. By manipulating a series of levers, the driver could alter the gearing, by varying the belt’s position infinitely between the larger, or smaller, diameter portions on the pulley. The system found favour in industrial machinery and, while some sources acknowledge the intention for…

► As an internal combustion engine generates maximum torque at certain crankshaft speeds, a well-engineered automatic transmission must hold the revs at this optimum point for maximum efficiency and then reduce them for the highest fuel economy at cruising speeds. While other types of automatic and automated manual gearboxes do this in stages, the stepless nature of CVT (in theory) is a more efficient method. In comparison, CVT gearboxes tend to be relatively uncomplicated and suffer from fewer parasitic losses, which is why their use was perfect for small engined cars, as well as lawnmowers, golf buggies and motor scooters. Regardless of vehicle age, the basic operating principles remain the same but they are easier to visualise, considering the original DAF/Volvo layout. Each belt and pulley arrangement is comparable with the…

HOW CVTs WORK ► As an internal combustion engine generates maximum torque at certain crankshaft speeds, a well-engineered automatic transmission must hold the revs at this optimum point for maximum efficiency and then reduce them for the highest fuel economy at cruising speeds. While other types of automatic and automated manual gearboxes do this in stages, the stepless nature of CVT (in theory) is a more efficient method. In comparison, CVT gearboxes tend to be relatively uncomplicated and suffer from fewer parasitic losses, which is why their use was perfect for small engined cars, as well as lawnmowers, golf buggies and motor scooters. Regardless of vehicle age, the basic operating principles remain the same but they are easier to visualise, considering the original DAF/Volvo layout. Each belt and pulley arrangement…