Appreciate your efforts. I'm guessing I'll be doing this someday down the road, although hopefully it will be a few years out.

 

Thanks for documenting your work. Actual photos generally are clearer than line drawings that are in the service manual.
Hopefully won't have to reference your work but it's a valuable asset to have.
My 07 has 40000+ miles and on it's original set of timing chains. I suspect most owners will not have a problem but there seems to be plenty that do. It would be interesting to know the root cause(s) of the failure.... that is why some do.... even multiple failures.
I've use Mobil1 5W-30 and change at 7000-7500 miles. OLM 45-50% until the PCM update and virtually no oil consumption between changes.
I did remove the upper engine shield AKA "Fuel Injector Sight Shield". Did about a year or so ago. My thinking was if there was a need to get at something it would have to come off anyway.... plus, and I have no supporting data, more airflow over the upper engine could produce lower temperatures. Also when I open the hood I like to see an engine, not a sight shield! I make no claims removing the shield has anything to do with improved chain life.

 

My 07 has 40000+ miles and on it's original set of timing chains. I suspect most owners will not have a problem but there seems to be plenty that do. It would be interesting to know the root cause(s) of the failure.... that is why some do.... even multiple failures.

I hesistate to call it a failure at 160K miles. This engine has been reliable - I have done fairly regular oil changes but by no means have I been obsessive about it. Same with air filters. Coolant was changed only because I had the radiator replaced when I hit a deer. Spark plugs have never been changed. Transmission oil has never been changed.

I think I'd call it something more like excessive wear than a failure. I will check the chain when it comes out but I suspect I will find it is "stretched" like others. Of course, all that means is that the pins have worn out the holes in the links. That's an issue of lubrication and use. Like I say, my engine has not been babied with maintenance, and I have used the SRX to tow jets skis and dune buggies. It's had a productive life, and I look forward to another 100K or so after this repair.

 

"Well, there's your problem."

Show this to your buddy that tries to tell you chains don't "stretch."

 

Pretty sure the OUTSIDE of the chain is not supposed to be a wear item:

 

I didn't think rats could get inside the crankcase and chew on stuff:

 

I think I got my money's worth out of this tensioner.

 

This is why you replace the gears, too:

 

Most of the wear was on the primary chain guides:

But even the secondary guides were worn:

Just so much whacking with a loose chain they will take before cracking:

 

Lots more pix and some diagrams at http://srxturnsignals.shutterfly.com/timingchain. When viewing albums, use the slideshow feature at fullscreen.

 

Sadly a vehicle that does NOT have the quality to run high mileage; my sister's Honda has over 200,000 miles with NO major problems...Since I am NOT a mechanic; dumping this poorly made engine is on the list soon.....so sad...GM HAS made dependable cars in the past; but too many vendors burned them on this POS!

 

To each his own. Plenty of Hondas out there with blown motors well under 160K, plenty of SRXs out there with well over 200K and no problems. Wish you had something more positive to contribute. Maybe you could start a different thread with complaints.

 

Sadly, that is what we mainly hear about these poorly made cars......Time for at least a Ford, and consider many foreign better quality products!!

 

Well, there are plenty of forums for whatever Ford or import you decide on, and I am sure they will be happy to have your posts. I hope you are happier there.

 

Yes go to the Ford forum and search "sparkplugs"

 

OK, let's get back on track.

So I guess I probably could have done a better job of changing my oil and keeping dinosaur juice out of my crankcase:

 

But nothing blue can Easy-Off, PB Blaster and a little elbow grease won't cure:

and

 

KTR-SB..... Thanks for documenting your T-Chain replacement so well.

We so need more threads like this.

It must have taken you twice a long to do stuff, since you stopped to take a photo with each step.

Why are there no photos of you stopping for a coffee, or beer break?

As for "Good Cars" and "Bad Cars"... all cars have their problems... even $300,000 ones. Just some have more then others.

My SRX happend to be my worse for problems - - my 92' Corvette was second worse. My 1976 Ford F150 4x4 was the very best, with 0 issues for the 8 years I drove it, and My 94 Infiniti i30 was the second best - with 0 issues for the 3 years I drove it (leased car).

 

Why are there no photos of you stopping for a coffee, or beer break?

lolz. I am a single dad, working 50+ hrs a week, two teenage boys. If I drank beer I would never get anything done, and if I drank coffee after the morning I would never get any sleep.

The SRX is my low mileage car. I have a couple of Intrigues that both have over 200K. Check out the work on them at 99intrigue.shutterfly.com. I squeeze in an hour or so when I can, the bulk of my wrenching is Friday night and Saturday morning.

Good thing I'm not married, can't imagine the girl that would put up with it.

 

Beautiful write-up here. Thanks for all the hard work.
I remember changing the timing chain set on my 71 GMC 350 V8 at 70,000 miles.
They had a nylon molded on aluminum gear on the cam that was prone to early wearout.
The hard part was you had to pull the oil pan to get the front cover off, LOL.

 

Tah-Dah!

Now on to the camshaft covers.

 

You are brilliant. You need to post a picture of yourself. Well done. You gave me confidence to DIY, well maybe not the timing chain, LOL. LXWXHT

 

Wow, you have accomplished a lot, being a single dad with kids and no time !!!!!

Hmmmm.... While you have that apart... perhaps you should consider High Roller Cams, balancing, blueprinting, boring, stroking, porting, and polishing it! Maybe a blower, along with an oversize, highrise intake plenum, and Equal Length Headers into 4" exhausts would work nicely.

You know...

When you have the time!

I am married to a wonderful lady who tolerates me and my "Toys". Not a lot of wives would tolerate a husband to have a 40k toy that just sits in his garage and only drives on the nicest of days! I also am into Motorcycles and do all the work on her Harley, and my Goldwing.

Besides - she gets brownie points with her motorcycle-riding girlfriends by offering my assistants with mods on their bikes! And she offers my help and advice to the kids!

I am very into cars, and I do all the work on my Mustang, including drive-train, suspension and electronics.

I would do the work on my SRX - however it is still under warranty, and I feel that GM should pick up the tab.

Here is my "Man Room" where I play with my toy.
(Click to Enlarge.)

There is not a lot of room under the hood to work!
(Click to Enlarge)

 

Wow, you have accomplished a lot, being a single dad with kids and no time !!!!!

Hmmmm.... While you have that apart... perhaps you should consider High Roller Cams, balancing, blueprinting, boring, stroking, porting, and polishing it! Maybe a blower, along with an oversize, highrise intake plenum, and Equal Length Headers into 4" exhausts would work nicely.

You know...

When you have the time!

lolz. Or the money. Since my divorce, my priorities have changed. Good thing I don't have the money to spend like I used to. Trying to save a 20 year marriage and then trying to save your kids from a less-than-ideal situation is not cheap. I thank the King of the Universe that I was able to do the more important of the two.

 

OK, remember these guys?

I think this looks better:

Removing spark plug tube seal:

PCV orifice (it doesn't use a valve):

Spend some time to make sure both sides are clear. Might make sense to put an air hose on it from time to time, like every oil change.

 

OK, I know I promised step by step, so here we go, from the top:

My 2006 SRX has the 3.6L V-6 engine, RPO Code LY7 (also known as the "High Feature, HFV6 and Alloytec). I have driven it since new, about 161K miles.

About a year and a half ago, it started getting very noisy at idle - a constant noise, somewhere in pitch between a whine and a roar. Like a bad bearing.

Then it started rattling, like the lifters had low oil, for about 5 seconds at startup. The noise was concentrated on the front of the engine, and did not seem to be coming from the camshaft covers. I only had the noise, no check engine lights (CELs).

The weak link (no pun intended) on these engines is the oil life interval and how it affects the primary timing chain. Many owners (CTS and other GM products use a similar engine) claim to have experienced noise and CELs associated with the elongation of the primary timing chain due to excessive wear. Some claim to have chain failures, with resulting valve to piston contact and damage. As noted by the next 2 posts, GM instituted a Customer Satisfaction program to re-program the engine oil life monitor.

I finally got around to disassembling the engine, and confirmed that the timing chain had elongated, had excessively worn the timing chain guides. The noise was likely from a combination of the chain slapping against the chain guides and tensioner shoes, and the worn teet on the primary chain gears.

This thread is intended to document for others how to go about making this repair. I have essentially done a "core dump" of pictures and information at my SRX's website, srxturnsignals.shutterfly.com.

To start with, let's familiarize ourselves with the LY7 engine. Here is what it looks like in the SRX (the CTS has a different oil pan):

In this writeup I will try to use the standard naming convention, where the front of an engine is the pulley side, regardless of its orientation in the vehicle, and the back of the engine is the flywheel side. In a RWD vehicle with typical longitudinal engine placement, this should'nt cause an issue, but this same basic engine is used in FWD vehicles as well. So the right bank is on your left hand, if you are standing at the front of the car, looking to the rear.

Also, cylinders are numbered, from front to back, 1, 3, 5 on the right bank, 2, 4, 6 on the left bank. Firing order is 1, 2, 3, 4, 5, 6.

My engine looks somewhat different, in that I have a factory-optioned towing package that includes heavy-duty cooling. So I have a different setup on the front, and I don't have the idler pulley between the harmonic balancer and the ac compressor.

Here is another view - it will help you understand some of the hoses, lines and nuts that need to be removed from the backside:

Here is a front view:

** You will note that there is an idler pulley between the crankshaft pulley and the air conditioning compressor pulley. Your vehicle may not have that - apparently it was deleted in early production. Good luck finding a replacement - I don't know if they now sell a different belt or what, but I can't even find a part number in my usual sources. ** [added by Mod per user request to avoid confusion]

So, to start with, jack it up:

Remove the lower deflector:

Drain the coolant (writing says have a splash shield ready, this is not a petcock):

Remove the strut bar:

Remove the engine cover (just pulls up after removing oil and ps reservoir caps):

Remove the air cleaner and duct:

 

Remove the fan shroud and cooling fan with bracket (mine has heavy duty cooling option):

Four 10mm head bolts, the trickiest one is just above the ABS unit on lower right side of vehicle. Use a 1/4 drive extension and a impact (ball and socket) style u-joint:

Fan bracket comes out with shroud, together. Do not disconnect fan from clutch:

The fan drive has an interesting coupling to the harmonic balancer - bushings and studs, no tool required to separate:

Disconnect brake booster hose to intake manifold:

Remove PCV fresh air hose from intake duct and left cam cover:

Remove dirty air hose from left cam cover and intake manifold inserts (left and right):

Remove and displace evap purge solenoid valve:

Disconnect electrical connectors:

 

Now time to remove the intake manifold (IM).

Remove insulator for intake manifold tuning valve:

It's a no-see-um 13mm head nut, attached to a ground stud (so be careful the stud remains tight). You can do as I and others have done and loosen the nut, but do not remove, and then tear the insulator:

Disconnect the drive-by-wire throttle body at front and move the retainer down:

I didn't get a closeup shot of it, but the main IM harness connector is a purple one, sitting on top of the right cam cover.

Remove the IM brace (leave the engine cover retaining ball stud alone):

And now the IM retaining bolts. The IM consists of an upper and lower section. To do the timing chain you remove both as an assembly. To do spark plugs, just remove the upper.

I'll sometimes start with the hardest bolt first. In this case, its the rear one. It is below the black MAP sensor, almost straight down from the bend in the manifold:

Use an extension to get to it:

The front one is less hidden:

Then remove the remaining four bolts and disconnect the main IM harness.

 

Set the IM assembly, with the fuel line attached, on the right cam cover/ strut tower (for access to the fuel line connector), and remove the locking clip:

Get a non-glass container (do as I say not as I do), a fire extinguisher, a non-glass-bulb drop light, a no-smoking environment, eye protection, some common sense, and a 3/8" GM fuel line disconnector (the wrench is an easy sizing method). Depressurize by depressing the schraeder valve, covered with a cloth:

A fair amount of gasoline comes out. Dispose of responsibly. You do not have to remove the injectors from the injector rail or the IM.

Remove the IM assembly and set in a safe place:

 

Remove the water outlet with upper radiator hose:

Remove the alt / wp belt:

Remove water pump pulley:

If you didn't drop any of the last 6 bolts into an intake port, now would be a good time to cut a piece of cardboard and tape it in place so you don't: