I was on my way to get the A/C recharged and when I got off the interstate I noticed a rattle. When I got to the shop, the mechanic listened and said it sounded like a timing chain. Sure enough, it's rattling.

I did some reading, realize it's probably the tensioners and that I'll have to basically disassemble the engine compartment to get to it to fix it.

How long do I have before it goes completely kablooey? I need to schedule some time to take her out of service to do the work, and would rather do the repair while it is still in one piece. Any suggestions?

Thanks!

 

2nd gen swap it. Find a 2014 ebay motor for six or seven hundred, Would be so much easier and you get an awesome new engine.

 

I know of a 3.5 that went tens of thousands of miles (over at least a year perhaps longer) with the primary chain guide broken.

When mine went, I replaced it within 100 miles. The job is no fun.

 

I am looking at my options. I just changed all the struts and control arms, a/c compressor, new tires... now this. If I can do the job myself, it's worth keeping. Otherwise, the prices I have scoped out for labor on the job make it impractical.

 

Your car is a 2000? The 3.0 usually won't have timing chain issues.

Hopefully all you need is the main tensioner which can be removed and reinstalled without pulling the timing cover. If that is the case the job is fiddly but straight forward.

What I was referring to is the more common 3.5 chain guide failure which is a much more involved job.

 

Oh really? Tell me more about this "Don't have to disassemble the whole damned engine" solution. I'm liking the sound of that.

 

My timing chain on my 2003 Infiniti I35 started to rattle at 170,000 miles. I did not want to risk damaging the engine so I took care of it right away. It is a project from hell but doable if you have time.

I removed the timing chain cover and replaced the main tensioner and all three guides (Top, Right side (small), left side (main)). It is possible to change just the main tensioner without removing the entire timing chain cover by removing just the small black window. But delicate hands are required because if you drop a bolt inside the timing case, you are SOL.

However, it is usually also the plastic guides that are brittle due to their age and constantly being exposed to heat. If you have to replace any one of the guides, it will involve removing the entire timing chain cover.

When I replaced my main tensioner, I noticed that the plastic on the guides were brittle. The pieces began to crumble whenever I accidentally bumped into it while working on the engine.

So I am glad that I did it the long and right way by removing the entire timing chain cover. My car runs better than it ever did now. I have driven it about 1000 miles since my repair from hell.

 

Yeah, I was reading through your thread on that. If I decide to take on a full remove/replace, it'll be the biggest repair I've ever done, so it's daunting. I'm trying to make sure it is the best path, and that I can pull it off, before actually committing to it.

 

Download FSM to get familiar with the timing bits https://www.nicoclub.com/archives/us...-database.html

Take the small access cover off and inspect the main tensioner and the guide (FSM calls it slack side chain guide). If the guide is broken the tensioner will be extended all the way.

Is your oil level good BTW?

 

Yeah, oil level is full and it hasn't overheated or had any other weirdness lately. I have been looking through the FSM, which is why I was actually considering trying to open it up. I'm already thinking that if I can access the tensioner and do the fix that way, I'll me using magnetized sockets so I don't drop anything into the timing chain cover...

 

If the guide is broken, you can cut down a new one and snap it in place. This has been successfully done by xterra owners, iirc.

And I agree, it's not worth replacing anything. It's literally easier to swap the engine. (and if you want to do chains/guides without going insane, then you're pulling engine, anyway)
You can get decent mileage 2nd gen DE for 300 bucks and the only thing you have to buy are the inverters. TB pigtail is the only other essential piece and that can be had from junkyard or may come with the engine (also can be ordered from china for cheap).

 

OP has a 2000.

 

How do you manage to break a 3.0? OP, you are skilled.