A Question of Timing

sioner – a device that keeps a firm and Subarus, Suzukis, Volkswagens & Volvos even tension on a timing belt. use interference engines. Most engines A Question of with four valves per cylinder are interfer- You can spend a thousand dollars or ence engines. Timing more on some cars, just on timing belt replacement. Most cars don’t cost this Where in doubt, assume that an much, but before you buy your next car, engine will be damaged by timing belt you’d better be damned sure that its tim- breakage. ing belt doesn’t need replacing. Unless someone else has replaced it already, you’ll Some engine manufacturers are get- be broke if you replace it and even broker ting the message – few modern Nissan if you don’t. If the service records for the motors use timing belts – they use a tim- t looks a lot like the belt that holds your car are not available, then you’ll probably ing chain system instead that in many Ipants up. It works in much the same have to rely on the little sticker that the cases outlasts the rest of the engine (there way as a bicycle chain, except that its job mechanic leaves inside the bonnet or were problems with the earlier versions is to link up various moving parts inside around the driver’s door. It will say when that appear to have been sorted out by your engine to make them all work at the the belt was replaced. If there’s no sticker now). However, there are still plenty of same time. For this reason, it’s called a then you must assume that the belt has older Nissans with timing belts, so be timing belt. never been replaced. careful.

In the old days cars had a steel chain to Some cars are worse than others: On If the vehicle you are looking at has do the same job and these chains tended some Toyotas the timing belt is good for done 100,000km and the seller (this to rattle as they grew old. Timing belts, 150,000km and even when it breaks it will includes dealers) cannot provide you on the other hand, are pretty well silent do no damage, but it will instantly strand with written evidence that the timing from the time they are first installed right you wherever you may be, including the belt has been recently replaced, then up until the time they break without warn- middle of a motorway on a wet winter’s you must assume that it needs replacing ing a few years later. night. However, on many other Toyota right now (unless the manufacturer says engines timing belt breakage will cause otherwise). Timing belts are one of those things major damage. that work best in an engineering textbook The seller should pay for all or most – they’re made of high-tech plastic, they’re The engines that you have to be wary of this, and it should be discounted off lighter than a steel timing chain, they tend of are interference engines. If the timing the purchase price. Do not agree to a to stretch less and, above all – they run belt breaks on an interference engine the final price for the vehicle until you have silently. This was the big attraction for engine valves will collide with the piston a firm quote from a reputable garage for carmakers. and bend or break. At the very least this replacement of the timing belt, tensioner means that the vehicle’s cylinder head and the pulleys it runs on. Sometimes the When they started breaking and will need an expensive overhaul or re- water pump is involved in the timing belt wrecking peoples’ engines, the carmakers placement, but in a few cases timing belt tensioning system, and so needs to be re- said that there was no problem with the breakage – especially at speed - can cause placed at the same time. This whole proc- timing belts – the real problem, said the total engine destruction. ess may be very expensive, so be warned. carmakers, was lack of maintenance – people weren’t getting their cars serviced It’s no fun to have any timing belt Dealers, by the way, will often agree often enough. break because it will instantly strand you, to do work like this and then either not but if it’s a non-interference engine there’ll do it, or farm it out to some dodgy back- Like most of the things that carmakers be no damage done and you’ll merely street mechanic who will do the absolute say, this is only partly true. The timing need to get your car towed to a garage for minimum possible and with the cheapest belts on some European models break repair. On any other vehicle you’re up for parts. Don’t fall for it. Insist that you get to long before their stated replacement major repairs. choose where the work is done and always time. Worse, although it’s easy to talk insist on receipts for the work. These re- about changing a timing belt as being Here’s a few general facts: the vast ceipts must include a list of both the parts ‘maintenance’, it can be a major job. On majority of recent European cars (in- fitted and their individual prices. a few models you need to remove the cluding many rebadged as Holdens) use entire engine. timing belts and most of these engines Once you own the car, do not put will be damaged if the belt breaks. Most off getting the belt replaced. Remember, Generally, the more modern the car, modern diesel engines fitted to cars, utes the damage a broken belt causes could the more work is involved in replacing the & vans use timing belts and virtually all exceed the purchase price of a cheap car. belt. And it’s not just the belt; the wheels these engines will be damaged if the belt And lastly, read our equally depressing that the belt runs around must generally breaks. Most recent Daewoos, Daihatsus, article, Keeping it Cool. That bargain car be replaced as well. Then there’s the ten- Hondas, Isuzus, Mitsubishis, Protons, you are looking at might not be quite the bargain it seems