Nissan Repair: KA2DE enging rattle, chain stretches, haynes manual

Question
I have a 98 Frontier that has a rattle form the motor.  It is the same rattle that occurs from the tensioner when the motor is started.  Occasionally this does happen but the rattle always occurs around 1900rpm.  I am wondering if this would still be tensioner problem. If so, would I change the the upper and lower, as well as the chains themselves.  How difficult,long would it be to do the job myself?  Thanks for any advise.

Answer
Peter,

You are probably looking at a chain replacement along with the guides and tensioner.  It is ten years old and the chain stretches and the chain tensioner and guides wear...  Plan on a weekend if you have the proper tools.  Once the radiator is out and all the accessories are off the engine then it is a matter of getting the crank bolt off the the harmonic balancer off.  Once this is done then it is the timing cover.  Once that is off you get to deal with the chain.  Get a chain kit from courtesyparts.com since they are cheaper than the dealership and Nissan parts fit the first time.  Also, a water pump since you are in there.  New gaskets, an oil change and antifreeze.  Also, get the gasket in a can to make the cover gasket.  Pay close attention to the timing marks.  Make sure you have rotated the engine to top dead center prior to disassembly of the cover and chain.  Note the marks on the chain and the gears.  Match up with the new chain.  It will be a little off with the old chain due to stretching.  I like to use touchup paint to dot the marks to make it easier to see.  Also, once you have the chain back together rotate the engine two times to make sure the dots matchup again, on top dead center.  If they do reassemble.  If not figure out where you are a tooth off and realign.  Repeat until the dots line up after two rotations.  Get a Haynes Manual or a factory service manual for the diagram and torque specifications.