why did my new timing belt break?

[foreveryoung]

broke going about 45mph .. its a new belt why would it break? whats the chances of valves being hurt? it already ran like crap and i think its happend to previous owner

[cougar289]

Well, there could be a variety of reasons, but here are a few examples:

Defective Belt
Improper Tension
Belt Tensioner Wore Out/Randomly Seizing
Camshaft Seizing from worn bearings or improperly torqued rocker arm assy.
The camshaft bearings will wear quicker if the previous belt was installed too tight.

How many miles on this engine?

[foreveryoung]

235k miles. the motor was loud when running. how can i check if bearings are ok ? thanks for help

[cougar289]

Pull the rocker arm assembly + camshaft and visually inspect the bearings for wear.

[foreveryoung]

cool, thanks

[foreveryoung]

got it on and its running better than ever, so i guess it was just faulty belt or incorrect tension.. i think my tension is too tight also , is there a way to check tension like pulling up on belt and counting how many teeth actually mesh with the belt?

also , my tensioner was very easy to spin could it be the cause of my last belt breaking or will it be obvious when tensioner is bad?