If the timing belt breaks, how do you know if you bent the valves or not? It's an '99 a4 1.8t.

 

first off don't crank the engine then fit a new belt then test it or do a compression test when the belts fitted, many look at this as a major problem and it is if you take it to the dealers when its a simple DIY.

should you require any information on how PM/email me

 

Most likely, yes. They're bent.

You can...

A: Install a new belt, rollers, and tensioner, spin the engine by hand, and perform compression and leakdown tests. If it passes all tests, say a prayer and let it fly.

or

B: Remove the head and look at them. Replace the bent ones and inspect the pistons for damage.

Good luck!

 

^techbod beat me to it.

 

there is much misconception over interference engines because the damage isn't always bent valves in many cases the belt snaps and they don't collided with the valves and the bigest problem is when you crank the engine and thats when the damage is done

 

True. Or if you were in the middle of a heavy-footed run through the powerband!

 

^^ done that lol

 

If the engine was running when the belt broke you did bend valves, it's just a question of how many.

 

its all a question of dynamics and engineering ( belt slips/breaks so top end stops dead and if the valves are in the prone to strike position they will bend ) on the other hand like the none interference engine the valves are pushed back out of harms reach so if the belt snapped/teeth broke the engine might be in the none interference state: valves/pistons in apposed position therefore contact is doubtfull, the dealers do the recommended ( fit new timing belt and check for damage ) its that simple

 

This is such a bummer, the car is so perfect in many ways and now mondo bucks to fix a car that's probably not worth the money to fix. Thanks for the fast response to my post. The belt broke rounding a 15mph corner.