How do you know when to change your car timing belt?

I have a Fiat punto 2002 that wont start. everytime i try starting it, it wont start. It sounds like the fan just switches on. I took it to a garage. They have said the timing belt has gone but i dont see how it is because it has not snapped.



The car mileage is only 28k.How do you know when to change your car timing belt?
i change my belts on every car i buy...yours is missing teath at the bottom....the crank spinns but the reat of the engine stays still...thats not the worst of it..your head/valves could be damaged....How do you know when to change your car timing belt?
You check your owner's manual. Unless something is defective, the belt should be replaced at the manufacturer-specified interval.



Even in the 70s, Fiats had longer timing belt intervals than that. Most modern engines have intervals of at LEAST 60,000 miles, and many are over 100,000.



If your timing belt was out, it would probably do more than ';sound like the fan switches on.'; Depending on what type of engine it has (interference or non-interference) it would either just not work, but should at least turn over, or you'd hear the pistons banging into the valves, pretty much destroying the cylinder head.



Oh, and the timing belt is not a belt that you can see on the outside of the engine. Being so critical to the function and health of the engine, it is encased in its own little cover. Almost every engine that has a timing belt does it like this. You have to actually remove the timing belt cover to see the state of the timing belt. What you're looking at is probably just an alternator, power steering, air conditioning, and possibly fan belt.
Take it to a different mechanic.



Maybe when they said it has gone they meant its worn down too much? I don't know. Mine snapped on me in my first car. I was driving home from work in the middle of winter and had to sit in my car for an hour till the tow truck came. I was on the highway but on a bridge thing (overpass?), my car just all of a sudden quit. I was lucky I was at the top though becuase I was able to coast down the rest of the overpass and get off on the offramp.



The only thing though is when it went it snapped and wrecked my pistons or something. So the whole engine had to be replaced.



Man 28k, sounds low for a timing belt. Yea, I'd get a second opinion. Good luck!



Edit: To the first answers comment: ';If the engine WON'T turn over when you turn the key, its a battery, starter or ignition switch problem.'; I don't think this is true, because when mine snapped it was like my whole car just died. Nothing worked when trying to turn it over.
Try taking it to another garage if you dont think its a proper estimate. You would have to take the valve cover off and check the valve train and the crank position to see if everything is lined up properly. but first I would: 1)Check ignition with spark tester inline with plug 2)Check fuel injection system by spraying intake with starter fluid, if it trys to run, something is wrong with fuel injection system.
The teeth can sheer off the belt, so it isn't snapped but not working.



Its easy to check.



Take the cam belt cover off (plastic cover)



Turn the engine over, the belt should move as the engine turns over. If it doesn't move when the engine moves, its lost some of its teeth,



Big job to fix as the head may need to come off.



Cam belts should be changed at 50k or 80k or 100k+ it depends on the engine and the type of driving.



I bet the 28K is 128K on a 2002



If the engine WON'T turn over when you turn the key, its a battery, starter or ignition switch problem.
rubber timing belts either wear out by mileage or by age. its only 28k but its almost 7 years old.

Now i dont know why you even mentioned a fan but you must have had it towed to the garage since it would not start. And did you really see the timing belt?? Because it is located behind a metal shroud,,,,it is not the belt that wraps around the various pulleys on the front of the engine.
The timing belt is usually time, as well as mileage related?And fiat is 5 years or 48,000 milesIf it wont start how did you manage totake it to the garage?The belt may have stripped the teeth and still be in place?Its sounds to me that the problem is the timing belt with the symptoms you are describing?
You need to remove the timing belt covers and try turning over the engine with the key. If the cam and the crank both turn, then the belt has not gone. If however when you remove the cover you find that the belt has snapped then its already to late!

Ja.
Look at the belt closely for cracks. Those cracks hinder the grip of the belt which may cause either slipping or loss of torque during starting.
if you are sure its not snapped, check it has not slipped due to teeth missing. but from what you describe it does not sound like its the belt.
Buy a Chevrolet.