Low-mileage cars, slow 20mph streets and alternator wear
Purley has a lot of well-kept cars that don't cover many miles. A car that pops down the A235 Brighton Road to the shops once or twice a week, or crawls along 20mph roads like Old Lodge Lane with its speed cushions, spends very little time at the steady revs that let an alternator recharge the battery. Over a winter the battery slowly loses ground, and when it's finally flat, the alternator is often blamed without being tested. Sometimes it's guilty. Sometimes it's the battery, which has been worn down by the same short trips.
The other side of Purley is hills. Around Russell Hill and up towards Riddlesdown Common, engines work hard at low speed on the climbs, and on newer cars the heaters, screens and fans pull a lot of current at the same time. An alternator whose bearings are going or whose decoupler pulley has worn will often reveal itself on those climbs first, with a whine that rises with revs or a rattle when you lift off. Heavy queues at Purley Cross and on Purley Way add more time at idle with everything switched on.
Our approach is to test, then quote. We check battery health and alternator output across a range of loads, allowing for smart charging on newer cars, and we listen to the alternator and pulley with the belt removed. If the alternator is at fault, you get a written quote for an OE-specification unit. If the battery is the problem instead, we'll tell you that honestly.
The drive is up Foxley Lane (A2022) through Woodcote, right onto the A237 and north through Wallington to Hackbridge, around 4.5 miles. If the car won't start at home, we can collect it rather than you arranging jump leads on a hill. All alternator work is covered by our 3-month workmanship warranty.