# 24V VR6 Timing chain overhaul, suggestions?



## kmot (May 29, 2009)

Regarding to my thread here http://forums.vwvortex.com/zerothread?id=4411768 I finally decided to take a closer look on that rattling sound and started to disassemble the engine.

When I got to the part where I had removed the camshaft casing I checked the timing, and the cams' notches did _not_ align perfectly with the crankshaft, when the crankshaft was on the marker and #1 TDC. I then checked how much more I needed to turn the crankshaft pulley and it was about 1 centimeter at the edge of the ring. I rotated the engine to right direction (clockwise) and repeated the timing check three times. Same result.

I calculated from there that the cam timing was something like 8 degrees late (give or take a degree or two) to the crackshaft.

Is this the same thing that the VAG-COM says that the Idle Stabilizer is at -8.0?

Are my chains streched? Am I correct in thinking that if my chains are streched enough, there's no such tensioner that could fix it? So I need to change both chains, rails and tensioners (and drop the tranny, which is a real pita to do.)?

So, I asked a few tips about dropping the 4Motion tranny http://forums.vwvortex.com/zerothread?id=4433517 but I'm still wondering if I'm going to do this all on my own, or just put it back up and drive it to some more experienced car mechanic. But I'm almost half way there...well a quarter at least.

As far as I can tell, the chain between the two cams is very tight and shows not sign of any wearing. But the upper and lower chain have some minor metallic like shine on some small surfaces, like it had rubbed against something other than just oily plastic? (Just speculating...)

I was thinking to open the upper chain casing and see if I can get more information about the condition of the upper rail guide and tensioner, and the both chains as well. 

Any tips or aswers to the questions above? I've already read this thread:http://forums.vwvortex.com/zerothread?id=1264409.

I'd still like to point out that there were no error codes or missfires or any other kind on issues with this engine, it ran very smoothly. Only the sound from the chains were the issue (see the link to it on that first line of this thread).

Sorry for the poor quality pictures (my Nokia phone's camera truly sucks).

Any input would be appreciated!



































_Modified by kmot at 2:52 PM 7-1-2009_


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## RedDevil (Sep 21, 2001)

*Re: 24V VR6 Timing chain overhaul, suggestions? (kmot)*

The timming marks seem to be way off. I would pop-off the upper chain cover and inspect the guides. The plastic guides are known to break.
http://forums.vwvortex.com/zerothread?id=3125706


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## PowerDubs (Jul 22, 2001)

*Re: 24V VR6 Timing chain overhaul, suggestions? (RedDevil)*

In my experiences the timing marks on the crank pulley are never right.
I have nothing else to add at this point because I hate to speculate without seeing it first hand. 
BTW- are you the original owner? That car has been driven a long time without changing the oil (everything stained burnt orange.)


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## Mr. Rictus (Sep 25, 2004)

*Re: 24V VR6 Timing chain overhaul, suggestions? (RedDevil)*


_Quote, originally posted by *RedDevil* »_The timming marks seem to be way off. I would pop-off the upper chain cover and inspect the guides. The plastic guides are known to break.


Where did you hear that the chain guides are known to break in the 24v VR6? I've only seen maybe 4 cars on this site with any sort of wear or braking issue.


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## RedDevil (Sep 21, 2001)

*Re: 24V VR6 Timing chain overhaul, suggestions? (Mr. Rictus)*


_Quote, originally posted by *Mr. Rictus* »_
Where did you hear that the chain guides are known to break in the 24v VR6? I've only seen maybe 4 cars on this site with any sort of wear or braking issue.

I had one and you *know* about the the other four!!








He might be number 6. But until he pops-off the cover we are just guessing here. But looking at one of his picture where marks are circled red there is no way this is right.


_Modified by RedDevil at 7:20 PM 7-1-2009_


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## kmot (May 29, 2009)

Thanks for the answers guys! And RedDevil: is that the upper tensioner in the picture?
I'm the fourth owner.
I'll report back when I have taken the upper chain cover off.



_Modified by kmot at 11:46 PM 7-1-2009_


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## silverstoned83 (Feb 16, 2009)

*Re: 24V VR6 Timing chain overhaul, suggestions? (PowerDubs)*


_Quote, originally posted by *PowerDubs* »_BTW- are you the original owner? That car has been driven a long time without changing the oil (everything stained burnt orange.)

I'm thinking the same thing. The built up coating that I'm used to seeing is a much more translucent yellow color. Definitely not a good sign as far as preventative maintenance goes...


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## PowerDubs (Jul 22, 2001)

*Re: 24V VR6 Timing chain overhaul, suggestions? (RedDevil)*


_Quote, originally posted by *RedDevil* »_But looking at one of his picture where marks are circled red there is no way this is right.

As mentioned above- In my experiences the timing marks on the crank pulley are never right. (meaning ignore them)


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## kmot (May 29, 2009)

Okay guys, the upper timing chain cover is now off.

The upper chain guide showed only little wearing, those lines barely felt to the finger:









The upper chain tensioner looked the same, as far as it could be seen with the chain on it:









There were no extra pieces of plastic in this slot:








Also, the top of the lower chain guide (visible in the picture above) moved gently sideways a bit when touched with a screwdriver. But not that much that it would indicate it being in two pieces, at least that's what I think.
Along the chain movement axis it did not move at all. The lower chain guide isn't bolted on, so I'm again guessing here, that it can move sideways just a little bit along it's pins and is therefore normal.

The hydraulic tensioner bolt has clearly not have been extended for it's maximum length, you can see it from this picture that it has been only halfway or so extended. So I'm guessing the upper chain had had no slack when the engine was running. And therefore the sound did not come from this. Do you guys agree? The pressure from the spring inside it felt okay and the bolt extended all the way when removed from the block. (not 100% sure of this though, since the pic was taken after 5 minutes of pushing and testing the thing)
Also the tensioner bolt oil holes were not clogged or the tensioner itself jammed in any way.









So, do I really have to drop the tranny?









What if, just what if, both the chain guide and the tensioner are just fine on the downstairs as well? where the hell is the sound coming from? It was clearly the chain noise (and not from the short cam chain on top) and the local VW repairshop listened to the sound too and told me it truly came from the chains.



_Modified by kmot at 3:11 PM 7-2-2009_


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## NastyBrown (Aug 13, 2005)

*Re: 24V VR6 Timing chain overhaul, suggestions? (kmot)*

Is vag com showing any fault codes for timing? Have you checked your intake shifter rod bushings?


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## kmot (May 29, 2009)

No fault codes whatsoever.
And the sound is definitely not coming from the rod bushings.



_Modified by kmot at 2:47 PM 7-8-2009_


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## kmot (May 29, 2009)

Okay, I didn't want to give up, so I finally managed to get the angle drive off, then the tranny, the clutch and so on...
Once the lower chain cover came off, to my surprise there were actually no broken chain guides or tensioners, but the tensioners (both upper and lower) had some peculiar looking signs of wearing, at the direction where the chain meets the tensioners.
I'm thinking the lower/upper/both tensioners have had some trouble keeping the chain tight enough and the chains have had a chance to slap with the tensioners.
But then again, I'm also thinking if my oil pressure was too low (but even at high RPM's?) for the tensioners to tighten the chain properly and that was making the noise? Did I perhaps do this all for nothing? But I've had no fault codes about low oil pressure. Or about anything for that matter. And the sound truly sounded like there was a broken chain guide/tensioner.
Nevertheless, I'm changing both chains and all rails/tensioners. And a new clutch, while I'm at it. At least then I don't have to worry about the possible total engine destruction.


_Modified by kmot at 2:50 PM 7-8-2009_


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## Mr. Rictus (Sep 25, 2004)

*Re: 24V VR6 Timing chain overhaul, suggestions? (kmot)*

I've just removed my timing chain as well and had signs of wear on the guides... the tensioner looked perfect. The wear was very minimal and I didn't have any peculiar noises prior to removal.


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## kmot (May 29, 2009)

*Re: 24V VR6 Timing chain overhaul, suggestions? (Mr. Rictus)*

So You just checked the chain condition, just for the fun of it?









I noticed today some wear on the side of the lower chain upper sprocket. Will post a picture of it tomorrow. Is it normal to have any chain signs on the sprockets?


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## Veedub_junky (Aug 13, 2005)

*FV-QR*


_Quote, originally posted by *kmot* »_So You just checked the chain condition, just for the fun of it?











It's the latest rage - everyone's doing it, lol. Except me, because I suck















to you for digging in there and getting it done yourself. Not too many I'd trust to do it for me (including me







). When and if the day comes, I'll probably DIY it http://****************.com/smile/emthup.gif


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## kmot (May 29, 2009)

I finally received the new parts today and started putting it all back together. Now with new chains and stuff the timing mark for the crankshaft is only a 3-4 millimeters off (late), when camshafts are aligned correctly.
I think that's the best it could be, considering how the marks were before (10 mm late, as in the picture on my first post in this thread).
I checked the timing at least ten times to be absolutely sure that the chains were not a tooth off on the sprockets.
The lower chain upper sprocket aligns perfectly with the according mark when the crank is #1 TDC so the lower chain just has to be correctly installed.
I then checked if I had the upper chain one tooth off (late or advanced) and that would have made the crankshaft timing marks about 3 centimeters off of each other. So I guess it just has to be correctly now.
I'm thinking what PowerDubs said above that they might be a little off anyway.


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## kmot (May 29, 2009)

Ok, this project has come to an end. I finally bolted the intake manifold and the rest of the parts and turned the key. And the engine started nicely and it purrs very smoothly, with no rattling sounds whatsoever.
I want to thank all you guys out there.


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## apstguy (Apr 3, 2006)

So it was simply chain stretch or was the tensioner weak?


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## kmot (May 29, 2009)

*Re: (apstguy)*

Well, I cannot be 100% sure, but both old chains had a bit of slack on all the rivets. Also when I compared the old and new lower tensioner, the old felt a bit weak. 

But aren't the both (upper and lower) tensioners oil pressure powered? So it should tighten the chain, no matter what the spring tension inside it feels like in my hand.


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## apstguy (Apr 3, 2006)

Yes, they are oil pressured. We've been seeing more and more chains stretching too. Trend or no?


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## PhReE (Sep 16, 2004)

*Re: (apstguy)*

Yeah.. I am pretty sure my chains are stretched too.


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## kmot (May 29, 2009)

*Re: (PhReE)*

In my non-professional opinion, as long as there are no misfires or fault codes (cam/crank position mismatch or something like that) and if the engine runs very smoothly, a little stretching does no harm. Other than the sound we hear and fear for the worst. Of course it depends a lot how bad the sound really is.
But then again, one cannot be 100% sure if it's the stretched chains or something else broken, just waiting to kill your engine.
In my case, after seeing the old timing parts, I'm quite sure that it would have lasted for way more than 10k, prolly some 30-50k since I drive nicely







.


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## PhReE (Sep 16, 2004)

*Re: (kmot)*

Yeah, I have a cam/crank correlation code. I'm not too worried about it ATM but it does cause the motor to run a bit funny sometimes as it doesn't do sequential ignition anymore. Trying to collect up moneys to fix it :/


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## kmot (May 29, 2009)

Here are some more pictures that I took during the disassembly:
























































The engine block in this last picture is not from this project, but from my dad's 1.6 turbo diesel leftovers...
In some pictures above it's very clearly shown that in 24V the upper chain cover is different from it's 12V counterpart, see the big hole where the thermhousing comes on top of. It's on the upper chain cover and not on the head itself, as in the 12V chain DIY is shown. There's one chain cover bolt under the housing that took some time to locate.
I'd also like to point out that I did this project with my dad, who is a retired car mechanic and this was still no piece of cake to me (him helping me here and there). So I would definitely not recommend this to be your first DIY project. I've had a few engine/tranny rebuilds before this one.


_Modified by kmot at 12:17 PM 7-21-2009_


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## kmot (May 29, 2009)

(nothin)


_Modified by kmot at 11:44 PM 9-24-2009_


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## Volkser (Jul 21, 2006)

I know this thread is old, but I really appreciate you sharing your insights. I might be doing this soon, as I have some chain noise, but would rather not drop the tranny again since I replaced the clutch fairly recently. Might have no choice though!


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