CATA timing chains

[aNUT]

LINK TO PHOTOS ​

Welp, I knew we'd be doing them eventually. 140K on the clock. This one had significant chain rattle for upwards of 10 seconds after changing the oil or if it was a very cold start. Intake bank 1 cam phase retard was over 9 degrees when warmed up.

I do not recommend pushing them that far. Probably ought to replace them when you hit the 7-8 degree range. At that point the tensioners can still take up slack so you don't risk skipping time. This one actually skipped after the motor was out & we were rolling it to TDC to lock the crank.

You can see how much more extended the old tensioners are vs the new ones.

 

[oilhammer]

Yep, VAG+chains=Fail. It sucks, because often the rest of the engine is pretty good. I know we've had several VR6 T'regs hauled off to the scrapper for chains. I guess a TDI is more worthy of saving, but boy it can't be a cheap job! CATA especially! At least the later V6 TDIs only have two chains, but not sure if they are any better longevity wise.

Crazy because I regularly see V6 MB diesels with over 300k and even a few over 600k and they have no issues at all.

 

[aNUT]

It's all Iwis in the end. Doesn't make sense the MB can do it and VAG can't. I don't know much about why the chains stretch as much as they do, especially the early TSIs. My wife's A4 only made it 90K before the tensioner was completely extended and slapping the cover.

This is not a cheap job, but the difference between 2 chains and 4 is negligible. I've been taking some spot checks on customer cars, looks like the 100-120K gen 2 3.0TDI motors are sitting in the 5-6 degree range. Obviously not a controlled study.

I do have 1 cayenne diesel customer. Interestingly Porsche recommended a 5K OCI. At 160K miles his car is sitting peachy at 4 degrees. RMS is leaking though. Gonna let that one be for a while.

 

[TurboABA]

That doesn't look like fun.... or a bill I'd want....
How are you checking for stretch? MVB 93 or something?
I could have a look at my CNRB with ~84k miles on the clock to see how it compares.

Regarding the "stretch" of the VAG chains..... I would say it's all about regular maintenance and proper oil\lubrication. I suspect everyone sees MBs without issues because most of those owners roll into the dealers and flash their cash..... this means more frequent oil change vs us frugal VAG drivers who try to squeeze all the yield out of our service intervals...... I'd go as far as guessing that MB dealerships will reduce the recommended oil change intervals to make more coin, but in the process they are inevitably extending the life of the chains as a result.

This is just theory on my end.

 

[aNUT]

Advance Measuring Blocks search "phase" & look to something like camshaft bank 1 phasing. I don't remember the exact address. Same general idea as MVB 93 on the gassers. Bank 1 is the right bank. The engine must be warmed up and running for a few minutes before you'll get a reading.

 

[bioburner]

I checked this on my noisy at startup CNRB (‘13 Q7 w 150k) and it was -4.5 at startup and dropped to -3.5 once up to operating temp.

 

[josiah47]

Just checked for funzies CATA 120k miles. -2.3 at idle 180 temp.

 

[A2VR6]

Thank you for sharing photos and the info. I'm replacing the chains on my 2012 V6 TDI, CATA engine code and seen if anyone can tell me the torque specs for the timing chains tensioner/guides?

 

[MrCypherr]

If you pass your VIN via PM, I can look up the specs.

 

[TurboABA]

If you pass your VIN via PM, I can look up the specs.

Reminds me of every single dealership parts department visit.....

Hi. I'm after a 2 boxes of oil for a '14 Touareg TDI

Do you have the VIN please?

 

[MrCypherr]

LOL, exactly what I was going after. "I need wiper blades" Got a VIN number?

 

[A2VR6]

If you pass your VIN via PM, I can look up the specs.

PM send. THANKS!