Whenever my motor is turning EXACTLY 2700 rpms there is a chatter from the valve train. Any ideas?

 

tensenor?

 

could be tensioner or the more common chain guide problem

 

At about what mileage does the tensioner or the chain guide go out? My car has 80K on it.

 

I guess it depends on how those 80k miles were driven... regarding the chain guides, there's a Nissan TSB that instructs you (or the dealer) to remove the upper 2 guides because they are known to break and/or make a distinct rattling noise

 

Is there any danger for serious damage to the engine if the tensioner is the problem? I'm use to working with pushrod V8's, so this is a very foreign part to me.

 

The tensioner keeps the chain taught against the cam gears. I think you know what happens if it were to jump teeth.

However, the upper top and upper/right chain guides are potantially more dangerous. The guides can break over time - which means a bunch of metal pieces flying around in the timing chain area, the oilpan, etc. The chain guides were deemed a serious-enough issue that Nissan put out a TSB to remove them.


I wrote a how-to recently on how to remove the guides:

http://www.project-raine.net/garageguides/index.html

It's a fairly easy job - if you've worked on V8's, you should be able to handle this job no sweat

 

Thanks for the help, I checked out the link and it shouldn't be much of a problem, and if it stops this god awful noise it will be very worth it.

 

Well today I pulled the chain guides off and checked the tensioner. Both were fine and the whole process went well (other than a bolt breaking). It took a bit longer than I expected just becuase I knocked the rotor off while removing the cap...haha. Well I was at it I threw in some NGK Iridium plugs and advanced the timing a bit. It runs a bit stronger now but there is still some engine noise. Any other ideas?

 

Ive heard water pumps chatter. Just a thought

 

Hey 12aine, your link http://www.project-raine.net/garageguides/index.html doesn't work anymore I believe that I need to do this next and tuneup the rest of the engine.

 

it's now http://garage.projectraine.com - new url, because I forgot to renew .net

 

well looks like ive got a nice full night ahead of me...