Hi All,

I apologize for likely asking a highly discussed topic (I hope not), I did do searches. I'm on the verge of buying a 2003 I35 from a local dealer, pretty decent dealer service history, only 80k miles, good shape overall. I had a pre-purchase inspection done and aside from a couple normal things that I'm not stressed about, the mechanic did find some oil (leaks). Without cleaning, driving, and re-checking (which isn't really an option during a pre-purchase inspection), he wasn't able to pinpoint where they're from.

I'm not worried about valve cover gaskets, oil cooler O-ring etc.. As an Audi guy, what I'm worried about is timing chains. Odds that the leak is from the timing chain cover is not super likely, but possible. And that bodes another question, how are the timing chains on these cars? From what I read, replacement is few and far between, but these cars are getting older. Do I have any material reason to be concerned about I35's in general with respect to the timing chain? This specific car didn't exhibit any rattle on startup, nor did it have any strange noises.

Thank you all for the advice/input, much appreciated !

 

The chains last a long time I have 200K miles on my I30 and my Maxima and have had no issues

 

I have 180,000 miles on my 2003 i35. The timing chains are supposed to last a long time. It is the timing chain guides which are made with plastic parts that will eventually give out. I had to replace my guides when my car was at 170,000. It was a bit of a pain but not overly so.

 

you replace them yourself?

 

Yes - I did replace them myself. It was a PITA but I had lots of free time during the COVID-19 shut down. While my neighbors did home renovation projects, I worked on my car. I had parts scattered throughout my garage.

I frankly had no choice. I called the local garages and no one wanted to touch my car given the age of it. But I am glad I did it. I learned a ton. My car started on the 1st try after I put all the parts back together again. SInce I had the timing cover off, I also replaced my water pump and thermostat.

 

i've looked and I don't see much working room, i'm guessing you didn't remove the engine
any tips for others that might need to do the work themselves? how long did everything take? anything to watch out for?

 

There are not that many helpful videos on this repair. But here are 2 that I found useful:

Instructions for removal:

Tips on putting it all back together:

You are correct. There isn't much room but God blessed me with small hands which is wonderful for a DIY mechanic It is a tedious job and many advanced DIY's on this forum recommended just swapping out the engine. But that is expertise beyond my pay level . Prior to tackling the timing chain tensioner issue, my most complex fix was replacing my AC compressor and condensor. I have patience and I can unbolt things. So I deciding to give it a try and thankfully, it worked.

As far as how long it takes, it is hard to say. I did it during the COVID lock down and I was laid off. So I was blessed with lots and lots of free time. From start to finish, I spent 3 months doing it. Now, don't let the time scare you. I did not work on it everyday. I did it when I felt motivated (nice sunny day). I went through weeks not touching it if it was cold and miserable in my garage.

But if you search around in this forum, the concensus is that it is definitely not a single day job. It is more like a long weekend job where you can spend hours on it. This is not a job where you want to rush it and have to do it all over again.

Good luck!

 

wow, yeah, thanks a lot for the info
what about tools? anything out of the ordinary that you had to purchase or have a special tool to recommend that makes life easier?
what about parts? what brand to go with and where is best to buy?
what bout cost? obviously you're saving a ton by diy, what was your total?

 

I have accumulated the basic tools over the years. Things like sockets, wrenches, extension bars etc. The toughest task was the removal of the crankshaft pulley. The bolt was a pain to loosen. I had an impact wrench which is worth getting. Electric ones are cheap on Amazon. Without it, you will waste a lot of time trying to unbolt the pulley.

Parts are cheap as you know. The timing chain guide that fails most often is the one on the left. It is made of plastic and metal. I tried to get cheap versions on Amazon. But they don’t look 100% the same as OEM. So I returned them and got an OEM one from my local Nissan dealer. It was $65 in 2020. I also replaced the second guide (the one on the top). That one was cheaper around $30. The plastic from the old one felt a bit brittle after almost 20 years. I proactively swapped it out.

Given how challenging this project was I did not want to risk using cheaper non OEM engine parts. So I spent less than $100 on OEM parts. As fun as it was, I did not want to repeat the project any time soon to save a dollar or two.

I might add that this was around COVID time when everyone stayed home except to drive to the grocery store. We have a second family car to use. That means I had zero pressure to finish it fast. I had the luxury to take my sweet time.

I have seen posts from others with similar timing chain rattles due to a failed guide. They decided to pay someone to fix it because they either don’t have the time or the skill to do the job. You have to decide for yourself.

I had nothing to lose and everything to gain. I was mentally ready to part with my old car even if I messed up the engine. So I got brave and gave it a try. It is one of those projects that once you start, there is no turning back.

It has been almost 2 1/2 years ago. My car still runs like a champ :-).

Close up of timing chain guide on the left side

Guide on top of timing chain