Thursday, September 22, 2011

When should I change my timing belt? 1997 Corolla?

I have a 1997 Corolla with 87,000 miles on it.

I took it to my mechanic a couple months ago and had him check the timing belt to see if it was worn--he said he couldn't see any cracks or evidence of it being severely worn, but also said that that didn't really matter because the timing belt doesn't have to have visible signs for it to snap.



When should I replace it %26amp; about how much does that cost?





Also, I've heard that there are two kinds of engines--ones that will be destroyed when the belt snaps and ones that won't and the car just shuts down. How do you know which type your car has?



Thanks!When should I change my timing belt? 1997 Corolla?
ive noticed that average milage is around 100,000 miles and that is when most auto makers recomend replacing the belts the average cost on all i do is 750.00 so good luck p.s. if a belt breaks more than likely it will cause more damage like bending your valves in the head real high dollar expenseWhen should I change my timing belt? 1997 Corolla?
Your mechanic was correct..a timing belt does not have to have any visible signs of decay/ wear in order to fail. Every car equipped with a belt has a specific mileage interval assigned by the manufacturer as to when the timing belt should be replaced; It is most commonly 60, 90, or 105 thousand miles. Not all engines have belts; most are chain or even gear driven; these do not require any kind of maintenance beyond regular oil changes.



As for the two types of engine, they are known as interference,and non-interference. In the interference engine, the valves and pistons are extremely close to each other, and if the belt breaks, or even jumps a tooth, the pistons can/ will bend or even break valves, which requires removal of the cylinder head to repair. Non-interference engines are designed with enough clearance so that if the belt breaks, the pistons cannot make contact with the valves, so no internal damage will occur.

Unfortunately, interference engines are much more common, especially on import cars. Your mechanic can tell you for sure which type you have.



As for cost, prices generally range from around $400, to over $1,000; some vehicles have more than one belt, or are much more mechanically complex to change. 4 cylinder japanese cars tend to be the cheapest; 4,6, and 8 cylinder german/ european cars are the costliestWhen should I change my timing belt? 1997 Corolla?
Your mechanic isn't being entirely honest with you. Belts don't simply snap all of a sudden after a given amount of time. Stress fractures, and fraying must and will occur before they actually break. Unless of course you live in an area where the temperatures are extremely low, in which case a sudden change in temperature mixed with a high friction ratio could cause the rubber to lose structural integrity and break. Replacing belts every 60-70,000 miles is a general rule of thumb simply because it is easier to remember and saves you if you happened to miss a bad place on the belt during inspection. If the mechanic saw no damage or deterioration, then I would feel safe keeping it on if he quoted you a high price for replacing it. It's hard to say exactly how much it would cost you. It could range anywhere from $200.00 to $800.00, depending on how much labor is involved. I've seen motors that only needed a prying bar and some elbow grease, and some that required the removal of entire suspension components and/or valve covers. It all depends on your particular engines orientation. As to your last question, any car can suffer severe damage or simply choke down when a belt breaks. Worst case, your valves drop as the piston is coming up (because without a belt it is now out of sync/time) and damages the valves, which is a major and costly repair. Best case, the fuel/air mixture will simply be so far off that the car chokes down and will not run. Any car can do either, it simply depends on where in the valve rotation cycle the cams are when the break actually happens. Hope that answered everything for you. And good luck with the car.