[ttaylor05]

Hi Folks,

I'm trying to make a decision on the most time/cost effective move forward, and could use insight from someone who knows these engines. I just traded in my 2012 TDI for the buyback last week (missing her dearly). Prior to that I drove a friend's 2008 FSI and decided I would get a T1 or T2 after giving up the TDI. In searching I found a 2007 3.6L in excellent condition (for its age), but with a reported timing chain problem. That wasn't enough to scare me away because I got it for so cheap.

I also had just finished rebuilding the engine on my wife's Audi, so I was feeling in the mood for another rebuild. Prior to turning in the TDI, I had the pleasure of driving out and towing her replacement home 700 miles...great times! Back home and on the scanner - it cranks but won't start, and is throwing no codes or CEL. The timing chain diagnosis appears to be correct.

My friend told me that starting in 2008, the timing chain issues (stretched chain, tensioner and bolt problems) were solved on the T2 3.6's, but I have yet to confirm. If this is the case, I might consider option A of tracking down an 08 or 09 motor for quick swap if possible.

Otherwise, I'll resort to option B, pulling in the crane and start tearing it down. If the issues are the same across the board, I wouldn't install anything else without installing new timing components anyway.

Any insight or input would be greatly appreciated! Thanks guys/gals.

 

[nickyt]

Your friend must be referring to the infamous oil pump bolt failure of the 2006 and 2007 VR6 engines.

3.6 Oil Bolt Failure: Reference Material

 

[buckwheat]

Ah yes! Leave it to VW to make a swap from timing belts to timing chains and end up with a set-up that is less reliable.

My understanding on the 3.6 VR6 was that the oil pump bolt breaking/backing out was the cause of the timing issues. To the best of my knowledge, the timing chains/guides/tensioners are not really any different on later models, but I'm not all that current on them. I do know that the guides that wear and are usually for the upper chain, which does not require the engine to come out.

In your case, you will definitely want to check the oil pump bolt, which is an engine or transmission-out proposition. If that is causing the problem, I'd probably swap to a newer engine, as I understand that pump may not have been spinning as fast as it should have been and it sometimes leads to spun bearings and the like.

If you are swapping in a newer engine, I'd have a tough time not doing a complete timing chain/tensioner/guide replacement. The failures are common enough, and the labor to fix it is significant enough that it strikes me as a reasonable insurance policy.

 

[noobytoogy]

The timing chain problem was on the earlier 3.2 V6 that the 3.6 replaced.

The chain maker carried on using worn stamps when making the chain parts resulting in some chains stretching prematurely. Replacing the tensioner helped in some cases but not all and since the engine was originally designed for east to west installation but is installed south to north in the Touareg, the timing chain is highly inaccessible at the back of the engine thus requiring it to be removed for the chain to be replaced unless you can find a female mechanic with tiny hands.

 

[nickyt]

Ah yes! Leave it to VW to make a swap from timing belts to timing chains and end up with a set-up that is less reliable.

That is the VW that we have come to know over these last few years. >

Since the OP seems to have no trouble pulling an engine, I would pull this one, remove the rear covers, and see what shape the timing components are in. If it looks salvageable, then compression test the engine. If everything passes, then I would just rebuild it.

At this point, it is a 50/50, but it will save a lot of money to not replace the engine. If the engine has to be scrapped, all that will be lost is the time to inspect it. The engine had to come out either way.

As far as the newer engines being better; the only real difference I have found is that a stronger oil pump bolt was installed at the factory.

Note to self. Put in the stronger oil pump bolt when rebuilding engine.

 

[nickyt]

The timing chain problem was on the earlier 3.2 V6 that the 3.6 replaced.

Always fun in the garage with a VW engine. >

I just remembered this thread. 2007 3.6 Vr6 sludge rebuild. 82k miles.

Perhaps the OP can get a second opinion about a rebuild from PanzerPerformance. I would say that he is the most knowledgeable person on this forum when it comes to taking a VR6 apart and putting it back together.

 

[buckwheat]

Timing chain issues go back even before the 3.2L. I had one of the first 2.8L VR6s made in a 1992 Corrado and found myself replace timing chain guides at 100,000 miles.

 

[ttaylor05]

Thank you guys for the insight - helped a lot and is much appreciated!!

I'm going to start with pulling the engine and opening her up to see if there is visible damage to any timing components. Hopefully I'll find a bad tensioner, bolt, etc. If it passes a compression test I'll install all new timing components, set it and should be good to go.

If lack of compression points to deeper issues, I'll buy a replacement and swap in new timing components (and bolt) before install. In that case I'd probably keep the core and rebuilt it in spare time when I want to get my hands dirty.

For the record it has 133k on the clock. Previous owner drove it for 6 years since it had 60k on it with no issues. He didn't do any timing work so its all original. Will start working on it next week and report back with the findings.

Thanks!

 

[77 K20]

I thought that oil pump bolt was just an issue on the Passat engines.

I take it that is not the case?

 

[nickyt]

I thought that oil pump bolt was just an issue on the Passat engines.

I take it that is not the case?

It involved the 2006 and 2007 3.6 VR6 engines. Models affected are any VW or Audi that had that engine installed. Wrong Bolt put in at factory. The fix was to replace the weak bolt with a much stronger bolt.

 

[PanzerPerformance]

The 3.6 in that truck is most likely got the updated bolt. I find very few had the issue in Tregs. Mostly early passat. With anything over 120k your in chain territory. Nice thing about these is the guides fail first. You get a cel for cam/crank correlation and then you fix it. No catastrophic failure most times.

Pro tips for pulling Vr6.
Removed hood
Remove fans.
Remove exhaust manifolds leave cats dangling in there.
Pull wiper cowl and disconnect harness at ecu and ebox panel
3 T50 torque converter bolts
Drain trans use floor jack under pan to get the angle of the dangle right
The torque converter will most likely come out when you go to pull it. Change that seal and wiggle/jiggle t/c till it's all the way home. It goes really far in.
Don't leave your rachet on the crank pulley bolt and smash into the radiator when separating the trans from engine like I did because replacing the radiator is a worse job than pulling the motor.