Timing chain is making noise

[srJOEYdet]

I took my car in for an Emmisions diagnostic, and they said it doesn't need timing, and than the nose I was hearing wasn't the valves, and that it was the timing chain rattling and hitting the side of the case. Are they full of it? I haven't heard much of this, but it seems to me like if the timing chain was loose enough to rattle it was too loose. And apparently it costs an arm and a leg to get replaced.
     I want to upgrade to an SR as soon as I get my alarm, and the money. it may be as long as a year from now though. because the dirty commies i work for won't give me any hours ehile I can use them (the summer)

The reason for this post is because rampid360 said "Other then that, make sure your timing chain is nice and pretty.  Nothing will destroy our engines faster then that going south. "

And it scared me a little. I willneed to look at mine tomorrow.

[DuffMan]

Remove your upper guide first and see if that solves it. If you are planning to swap I wouldnt worry about it. The DOHC engines are hardly ever actually destroyed by it.

[sporty240]

here's a little heads up on timing chains and the 240. it's  very common thing to have chain rattle in our KA24s, and it's not necessarily a bad thing. I got a lot of info off 240sx.org and my local nissan $tealership on this one.
the chain normally rattles and slaps around in there before it's warmed up, at idle. There is no cause for alarm, and the only thing the nissan place will do is a quick easy fix (which will cost over $100 for them to do so do it yourself) is to remove your valve cover and remove your top chain guide. This is an unmistakable metal bracket held down over the chain by just two bolts. 10 to 1 there's chain marks on the underside of the bracket. This is standard nissan procedure and there was even an advisory floating around from nissan that this is common. After I removed mine, there was still a little rattle but not much.
Now, worst case scenario is the lower valve guides are gone or the tensioner is actually stuck. This happens because some stupid engineer decided to make the guides out of........plastic.  It doesn't take an engineer to easily figure out that a metal chain will eventually whack at the plastic enough to break it into bits and pieces - and this is what happens.
I've got a headache and I can't think straight but i hope that helps

-Ben

[rampid360]

Didn't mean to scare ya &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'> &nbsp; &nbsp;IIRC, timing chains shouldbe looked at (not necessarily replaced) at like 100k miles or something really high. &nbsp;
They rattle around a bit when the car starts up, but thats about it. &nbsp;Some people take the upper guide off to quiet the rattle...but I've never had mine make enough noise to concern me.
I've spoken to a few people who have had a timing chain go on them, and consequently had to replace pretty much the entire top end...which is costly.
Im sure that if there's no crazy ammount of play in the chain then you're ok. &nbsp;The rattle is no big deal.
-Al

[240 2NR]

I say get some cams and pull the valvecover. &nbsp;If the guide is busted, send back the cams and start saving money to get that fixed. &nbsp;If it ain't broke, be happy you just saved an a$$ load of money and instead spend $300 on cams that you can now install because there's no cover on your engine.

[srJOEYdet]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (240 2NR @ Aug. 12 2002,2:42)</td></tr><tr><td id="QUOTE">I say get some cams and pull the valvecover. If the guide is busted, send back the cams and start saving money to get that fixed. If it ain't broke, be happy you just saved an a$$ load of money and instead spend $300 on cams that you can now install because there's no cover on your engine.</td></tr></table><span id='postcolor'>
Great trian of thought. I am not gonna mod my KA any more though. I'll go pull that chain guide anyway. As soon as I get my car back from the alignment shop (for my camber bushings and a replaced, severly damages tension rod... curbs are a b*tch)
&nbsp; &nbsp; I accually already knew it was useless, and I asked the dealer about it. They said they had never heard of removing it. Then again they don't know a damn thing about my car. I just go there to look at the FSM because I am too cheap to buy one. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'>

Joey

Thanks guys

[240 2NR]

Even though they suck compared to the FSM, most libraries carry the chiltons manuals. &nbsp;I had to sign one out for my gf's altima (which is paired with the 240 oddly enough). &nbsp;For a beginner though, I think the chiltons manuals are easier to follow, since they use actual photos and long descriptions, but are far less technical or complete.

[Powerzen2002]

Hey, as for DOHC engines, the guide on the top of the chain is more or less useless. &nbsp;HOWEVER, in the KA24E SOHC, that guide actually GUIDES The chain from flippin off. &nbsp;The chain in a DOHC engine is very stable, these guides break left and right. In your engine, its actually SIMPLE to change or remove. &nbsp;If you bring it to the dealership, bring your liver and a leg to pay for them to put in a 100 dollar part. &nbsp;THEY WILL charge you a few hundred to do this. &nbsp;If you do it it will be maybe a 1/2 hour if you HAVE NO idea what your doing.

My opinion, open it up. &nbsp;Take it out so it dont fall into your oil pan, and get sucked into your oil pump. &nbsp;Buy the new one and screw it back in.

Good luck.