I am normally a Mk3/Mk4 TDI person. My son, however, has a well-running 2011 GTI (CCTA) with 125K miles. It has only recently come to our attention that the TSI engine family apparently suffers from a few "weak" areas - in particular the timing chain and balance shaft systems, about which we have been attempting to rapidly educate ourselves.
Yeah....we're a little late to the party.
My son took the car to the local dealer and paid for a detailed evaluation. The dealer stated that the engine "failed" timing system check. They also said that cam cradle is leaking and recommended that the leak be repaired "at some point".
I performed my own checks when the car returned. Indeed, it has the old style timing chain tensioner. Additionally, VCDS 093-3 Phase Position indicates -5.03 degrees. So - it appears that timing chain system service is in order. The cam cradle is weeping as well. It seems to me that the best time to deal with the leak is when the timing system is already apart - not later when everything would have to be disassembled (again).
Given all that I have read concerning balance shafts and oil screen blockages, we are seriously considering proactively replacing them at the same time as the timing chain hardware. There are no indications of trouble with the balance shafts - but then it seems that there is little, if any, warning of failure.
I have been reviewing countless videos and pages regarding this work and noticed what seems to be a glaring omission in nearly all of them - I have found only a couple of references of any kind to the bearings at the far end of the balance shafts (pressed into the block?). From what little I have seen, they appear to be plain bearings. Even the local VW dealer parts department could not confirm. They took their best shot and gave me part numbers for needle bearings (with three different color codes) on the closest engine reference they could find to ours - a 2014 CNSA/CNSB engine. I purchased the electronic VW service manuals (erWin) and found that they had a glaring absence of information about this bearing as well. No bearing is apparent in the exploded diagram (unless I missed it). One would think that there is no bearing there at all! I know that the far end of the shaft has to spin in something - and I doubt that it spins directly in the block (surely not!).
So, assuming that there are bearings at the far end, my questions are these:
- what is this bearing (part number/description)?
- how does one inspect these bearings and what should the dimensions (clearances) be?
- how does one replace these bearings (if necessary)?
- where does one buy these bearings (they do not seem to come with the balance shafts)?
- why does no one talk about these bearings? It appears to be a normal plain bearing with no filter screens.
- what are the consequences of removing the filter screens on the balance shafts prior to installation? The bearings at the far end of the shaft do not appear to have filter screens and yet there do not seem to be any issues with scoring or oil starvation (at least none that anyone talks about).
I recently watched a joint video put out by the "Humble Mechanic" and "Deutsche Auto Parts" regarding timing chain replacement on a 2010 Tiguan (owned by Jalopnik senior editor) with similar mileage to ours. I know that it is a different vehicle, but it seems the base engine is from the same family with (presumably) similar issues as my son's GTI (in the info section, they did point to CCTA links and parts). I noticed that he did not proactively change the balance shafts, despite the known issues with the filter screens. I wondered why. I appreciate Charles' videos and I wanted to attempt to email him, but I do not know the best method to contact him and get a detailed and timely response. I'm sure that he is pretty busy.
Interestingly, I have found some Russian YouTube videos talking specifically about this bearing (in an Audi Q5) and even looking at it up close with a nifty bore-scope. The engine looked like the same CCTA engine family but, unfortunately, it did not involve actually changing it out. I saw another similar video (again, Russian) where the narrator made an extraction/installation tool on a lathe - but he had the engine out of the car. I don't believe that it should be necessary to remove the engine from the car, as there do not seem to be any shoulders in the bearing bore that would block extraction of the bearing out the front (with the right tool). Would have to pull it out.
Whatever we do, I want to give the engine the best chance of running another 100k miles without needing to go back and change something that should have replaced while everything was disassembled the first time. Is that realistic? What are the odds of the original balance shafts running another 100k miles? From what I have been seeing, I would say that it is unlikely. It almost sounds like this timing chain/balance shaft design needs to be viewed as a timing belt in terms of regular, scheduled replacement. Sigh.
So here we are. The dealer cost estimates for the basic timing chain work were pretty steep and I don't know about the quality of their work. So - we will be doing work this ourselves. We have not yet started the work and my son has stopped driving the car out of an abundance of caution. Fortunately, he is able to carpool while we are working this out. Trying to answer the last few questions and start moving forward.
We would also welcome GTI Mk6 parts supplier recommendations for this job - including being able to talk to someone knowledgeable on the phone. Our preference is for genuine parts where possible.
Apologies for the wordy description and all of the moving parts. I especially apologize if this info is already covered elsewhere on this site - just point me in the right direction, please.
Yeah....we're a little late to the party.
My son took the car to the local dealer and paid for a detailed evaluation. The dealer stated that the engine "failed" timing system check. They also said that cam cradle is leaking and recommended that the leak be repaired "at some point".
I performed my own checks when the car returned. Indeed, it has the old style timing chain tensioner. Additionally, VCDS 093-3 Phase Position indicates -5.03 degrees. So - it appears that timing chain system service is in order. The cam cradle is weeping as well. It seems to me that the best time to deal with the leak is when the timing system is already apart - not later when everything would have to be disassembled (again).
Given all that I have read concerning balance shafts and oil screen blockages, we are seriously considering proactively replacing them at the same time as the timing chain hardware. There are no indications of trouble with the balance shafts - but then it seems that there is little, if any, warning of failure.
I have been reviewing countless videos and pages regarding this work and noticed what seems to be a glaring omission in nearly all of them - I have found only a couple of references of any kind to the bearings at the far end of the balance shafts (pressed into the block?). From what little I have seen, they appear to be plain bearings. Even the local VW dealer parts department could not confirm. They took their best shot and gave me part numbers for needle bearings (with three different color codes) on the closest engine reference they could find to ours - a 2014 CNSA/CNSB engine. I purchased the electronic VW service manuals (erWin) and found that they had a glaring absence of information about this bearing as well. No bearing is apparent in the exploded diagram (unless I missed it). One would think that there is no bearing there at all! I know that the far end of the shaft has to spin in something - and I doubt that it spins directly in the block (surely not!).
So, assuming that there are bearings at the far end, my questions are these:
- what is this bearing (part number/description)?
- how does one inspect these bearings and what should the dimensions (clearances) be?
- how does one replace these bearings (if necessary)?
- where does one buy these bearings (they do not seem to come with the balance shafts)?
- why does no one talk about these bearings? It appears to be a normal plain bearing with no filter screens.
- what are the consequences of removing the filter screens on the balance shafts prior to installation? The bearings at the far end of the shaft do not appear to have filter screens and yet there do not seem to be any issues with scoring or oil starvation (at least none that anyone talks about).
I recently watched a joint video put out by the "Humble Mechanic" and "Deutsche Auto Parts" regarding timing chain replacement on a 2010 Tiguan (owned by Jalopnik senior editor) with similar mileage to ours. I know that it is a different vehicle, but it seems the base engine is from the same family with (presumably) similar issues as my son's GTI (in the info section, they did point to CCTA links and parts). I noticed that he did not proactively change the balance shafts, despite the known issues with the filter screens. I wondered why. I appreciate Charles' videos and I wanted to attempt to email him, but I do not know the best method to contact him and get a detailed and timely response. I'm sure that he is pretty busy.
Interestingly, I have found some Russian YouTube videos talking specifically about this bearing (in an Audi Q5) and even looking at it up close with a nifty bore-scope. The engine looked like the same CCTA engine family but, unfortunately, it did not involve actually changing it out. I saw another similar video (again, Russian) where the narrator made an extraction/installation tool on a lathe - but he had the engine out of the car. I don't believe that it should be necessary to remove the engine from the car, as there do not seem to be any shoulders in the bearing bore that would block extraction of the bearing out the front (with the right tool). Would have to pull it out.
Whatever we do, I want to give the engine the best chance of running another 100k miles without needing to go back and change something that should have replaced while everything was disassembled the first time. Is that realistic? What are the odds of the original balance shafts running another 100k miles? From what I have been seeing, I would say that it is unlikely. It almost sounds like this timing chain/balance shaft design needs to be viewed as a timing belt in terms of regular, scheduled replacement. Sigh.
So here we are. The dealer cost estimates for the basic timing chain work were pretty steep and I don't know about the quality of their work. So - we will be doing work this ourselves. We have not yet started the work and my son has stopped driving the car out of an abundance of caution. Fortunately, he is able to carpool while we are working this out. Trying to answer the last few questions and start moving forward.
We would also welcome GTI Mk6 parts supplier recommendations for this job - including being able to talk to someone knowledgeable on the phone. Our preference is for genuine parts where possible.
Apologies for the wordy description and all of the moving parts. I especially apologize if this info is already covered elsewhere on this site - just point me in the right direction, please.