Take it to the stealership. The only way to get to the tensioner is to build your own tool. If you were the type who could build his/her own tool, you wouldn't be posting on answers.com.
You should change it when it becomes frayed cracked, or loose. It should last at least 100,000 miles.
never
Change the belt
the miles are 81000 of Honda odeysse 2004, When should change of timing belt?
There is no timing belt on 2004 Honda accord, but a timing chain.
very carefully
That I know of, there is NO serpentine belt, unless you are talking about the the Timing Belt (hardly serpentine, but anyway), it has a belt tensioner, not automatic, though.
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You don't as the 2004 Honda CRV uses a timing chain and not a belt. It should last the life of the engine.
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