95 kA timing chain replacement question
 

Hey Guys, I have a 95 240sx with about 160k on the clock, and the timing chain is starting to make a rattle. After reading about how in some cars the chain will eat through the case and into a water line I decided I need to look in to this before it kills my car.

I am somewhat mechanically inclined, but I have never done a job like this before. I saw a guide on doing it a while back, but I can't seem to find it anymore, so I took my car to my local mechanic, to see what he thought. He says that the upper chain could easily be replaced, but the lower one is something like 12 hours of work in his billing book.

Basically, I think this job may be a little over my head, and even though I am strapped for cash I guess paying for the chain replacement is better then needing a new motor, but does anyone know if I can get away with just replacing the upper chain and the tensioner? or is it better to just do both?
Also I have seen some stuff about getting rid of the guides for the timing chains, should I be purchasing all of them?

Would I need to purchase:
2 timing chains (upper and lower)
2 pensioners (upper and lower)
Guides? Do I buy all of the original guides, or leave some out?

If anyone has done this at a shop before could you give me an idea of what I am looking at in terms of parts and labor? I have a feeling this is going to cut really deep into my summer tuition savings, but I guess since I need a car to function I don't have too much of a choice. Thanks in advance for any help.

your not supposed to replace the upper guides. Your supposed to remove them, thats probably the reason your timing chain rattles.

Remove the top guides. There are 2 of them, one at the very top and one by the distributor. If its still making noise, one of your bottom guides have mostly likely broken.

does that keep the chain from eating into the engine?

The bottom guides stop that from happening.

Remove your top guides first and see if it still makes noise.

if the bottom guild look good then he shoulnt have 2 replace them right?

Does anyone know if you can see the lower chain guide after removing the camshaft sprocket cover? I want to be able to inspect it, but it looks like it may not be possible unless I remove the whole front cover, which may require moving the engine, or removing the radiator.

You wont be able to see the lower guides, theyre way down there. You would end up taking all the front covers off plus oil pan IIRC.

That right there is no fun at all and if you can get rid of the noise with just the upper guides... let it be.

Also, theres a sticky written up on how to do this. I forgot which section it was, but it gives you all the details you need to do all this.

I found the sticky, and did it today, when you have the valve cover off, and the cam sprocket cover off, you can get a good look at the lower timing chain, and it's guide.

I removed the two upper guides, luckily they were in good condition, and not broken. I also checked the upper and lower tensioners to make sure they still had their full range of motion, and put it all back together.

I am very happy to say NO MORE RATTLE! ! ! Thank you guys very much for your help!!!