Timing Belt Tensioner Failure - Installer Error

Steve Addy

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I'm in agreement with others about this, just move on and make the necessary repairs so that your car is back up and running again. I doubt that you'll get any satisfaction from the mechanic who did the work improperly, the condition of the tensioner isn't definitive proof that it was tensioned backwards (ccw) although we all know that it's likely to have been the case. Getting someone in court to say that there's no other way to get that result except with improper tensioning...that would be difficult.

I guess if your engine suffered no damage at this point you're luckier than some people out there who also had mechanics who don't know how to tension timing belts.

As for the IP pin not being out when the belt is tensioned, I've never felt like that mattered one bit in the grand scheme of things, it's far enough from the tensioner that TBH it's not a relevant point. In fact I would argue to those who suggest that it is just how they intend to verify timing alignment if the pin is withdrawn? If you only have one immovable point (crankshaft) then everything else get's changed during tensioning. So technically once you go round a few times with a ratchet in theory you shouldn't be able to install the pin with the crank at TDC. But I digress....

The manufacturer of the tensioner is unknown but likely not a well respected brand, especially coming from Hans, so there's no point in dwelling on it. As for whether it would have failed simply because it's not a known maker, that's probably not something we're going to ever know.

If it were mine I would just go through the procedure of installing the timing belt again and check to see if everything looks ok. That you were able to remove the tensioner without taking the belt off bothers me a little since that's not typically something you can do unless there's a lot of belt stretch. If the belt is bad just replace it as well, most belts are around $20 for this engine so no great loss.

The real test will be turning over the engine a few times MANUALLY with a ratchet. If there are no collisions during this phase you likely survived, but you should also inspect the valve lifters when you pull the VC to set the cam plate. Any cracks or damage to the lifters will surely mean there was a collision.

Just be glad you got away without a destroyed engine at this point....

Steve
 

MukGyver

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Benjamis, I don't think it's rolling the dice not to replace / rebuild the head since you are sure the cam and crank are in correct position. I can't imagine either that it jumped the track and fell back into perfect time.

Pulling the cam to look at the followers sounds like a great idea though, since everything's apart for the TB now anyway. It would give you a chance to see how the cam is wearing on the followers and you could replace all that now if needed.
 

Steve Addy

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Why is that tensioner-tab notch 1-inch tall? From memory, it should be about 1/4-inch square.
I have a spare engine rolling around the shop on a cart with no TB on it, I'll see if it's consistent with his.

EDIT:

As a point of interest, I believe that the tensioner Hans is selling is either 1) branded ÜRO or 2) from the same source as those being sold by ÜRO. The component pieces appears to be the same. Note the beige plastic piece on the front in particular and the date marks.

Further, ÜRO doesn't mark all the products they repackage either, so the fact that it doesn't possess the ÜRO moniker anywhere is not surprising. ÜRO doesn't make anything so I have always considered them to be a bottom of the barrel Beck/Arnley in many respects.

This is not a tensioner I would use unless I had no other option. In fact I would trust a used Litens tensioner that had a good quality bearing before I wasted money on a ÜRO tensioner.





Steve
 
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KLXD

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This I will never know. The mechanic won't respond to me ever since I let him know what he did wrong. He doesn't stand behind is work and is easily offended.
I meant when you put it back together, rotated the motor and things didn't line up. You were using the crank bolt to turn the motor over I hope.

As for Steve's belief that it doesn't matter if the pump pin is removed for tensioning, if you don't and there's slack between the two fixed points you're going to have, the crank and pump, the cam will go retarded as the tenioner takes up that slack and ends up putting less tension on the belt.

The idea that leaving it in holds the timing where you want it doesn't make sense. It will move once the pin is remove whether one removes it before or after setting the tensioner. The difference will be whether the tensioner is properly set or not. Yes, the pin won't go in the hole anymore. That's the nature of the AHU belt system design.

In fact, if it's off more than a tooth's worth you'll see it right away and know you had too much slack between the crank and pump and can fix it before turning the engine the two turns and wonder why things don't line up anymore. Distance from the tensioner doesn't matter, It's a fixed length toothed belt system.

Might make little difference, might make a lot. Depends how much slack was trapped between the cam and crank.

And if critical thinking doesn't convince you look at the procedure in the book.
 

turbodieseldyke

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Yes, the pin won't go in the hole anymore. That's the nature of the AHU belt system design.

In fact, if it's off more than a tooth's worth you'll see it right away and know you had too much slack between the crank and pump and can fix it before turning the engine the two turns and wonder why things don't line up anymore.
But things already don't line up. You remove the pin, and as soon as you apply tension, the IP is pulled forward and the pin no longer lines up -- before you even rotate the crank 2 turns. That's a stupid design, or a communication error. The manual should tell you, "Insert pin; yada yada; Remove pin; Rotate engine; If the pin misses the mark by 2mm, then it's in exactly the right place."
 

Steve Addy

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I meant when you put it back together, rotated the motor and things didn't line up. You were using the crank bolt to turn the motor over I hope.

As for Steve's belief that it doesn't matter if the pump pin is removed for tensioning, if you don't and there's slack between the two fixed points you're going to have, the crank and pump, the cam will go retarded as the tenioner takes up that slack and ends up putting less tension on the belt.
Key point here, there is NEVER ANY REASON to allow for slack between the crank sprocket and the IP. In fact that's one of the difficult parts of this process on the 1Z/AHU, making sure there's zero slack between those two points while still making sure that the crank sits at TDC and doesn't move.

But further, I would bet that if you did manage to get a belt installed (unlikely) with an extra tooth of slack between the IP and the crank sprocket 1) you would be miffed because you couldn't get your cam sprocket installed or 2) if you did get the cam sprocket installed, when you go to tension the belt you'd pull the crank off TDC.

The idea that leaving it in holds the timing where you want it doesn't make sense. It will move once the pin is remove whether one removes it before or after setting the tensioner. The difference will be whether the tensioner is properly set or not. Yes, the pin won't go in the hole anymore. That's the nature of the AHU belt system design.
I don't believe I ever said that. And "the pin won't go in the hole anymore," is contrary to what one normally does after two manual rotations; they check to see whether the IP pin and the cam plate all fit back in when the crank is at TDC. That's how you check your work.

In fact, if it's off more than a tooth's worth you'll see it right away and know you had too much slack between the crank and pump and can fix it before turning the engine the two turns and wonder why things don't line up anymore. Distance from the tensioner doesn't matter, It's a fixed length toothed belt system.
Yes, You will know right away, because any slack is too much here, in fact with the crank at TDC you have to depress the IP lock pin slightly in order to get the belt to engage at the correct tooth, that's exactly how it has to fit with the two components at their desired positions.

Might make little difference, might make a lot. Depends how much slack was trapped between the cam and crank.

And if critical thinking doesn't convince you look at the procedure in the book.
As I said before, if you've left slack in the belt between the crank and IP it will likely pull the crank off TDC when you tension the belt, and once you go round twice manually and check you'll find that things aren't lining up.

I'm not trying to say that the VW process isn't ok, but the degree of movement at the IP will be extremely small, but it will be there and it will make reinstalling the IP pin and checking for TDC at the crank a fudging issue as you bump things back and forth to find the right spot. I've done it both ways actually, just because I could.

In the end it's not worth arguing about, but IMO the comment about critical thinking was unnecessary.

Steve
 

KLXD

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But things already don't line up. You remove the pin, and as soon as you apply tension, the IP is pulled forward and the pin no longer lines up -- before you even rotate the crank 2 turns. That's a stupid design, or a communication error. The manual should tell you, "Insert pin; yada yada; Remove pin; Rotate engine; If the pin misses the mark by 2mm, then it's in exactly the right place."
I wouldn't say it's a stupid design. It worked from the IDI days until it changed with the AHU. The manual does tell you to install the pin, install the belt, remove the pin, tension the belt. But no, no comment on how far the the pump will be off when the belt's tight but common sense will tell you it shouldn't be off by much.

Stupid design? Idunno. You can adjust timing with the engine running. Can't do that with the AHU.
 

turbodieseldyke

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But no, no comment on how far the the pump will be off when the belt's tight but common sense will tell you it shouldn't be off by much.
The book says to align all 3; lock cam & crank in place; remove IP pin; tension belt; rotate engine; check alignment .... and [paraphrased] "if cam and crank are good, but IP is slightly out of alignment, then loosen the pump to make it fit".

There is no "if". When the 3 pieces are aligned on a loose belt, and 2 of them are fixed in place, then the 3rd one is guaranteed to move when the belt is tensioned.

On the belt i changed last month, if i had followed the book and loosened the pump to make the IP pin fit the hole, i would have retarded it and probably had a no-start. And then i'd have to skip the pump one tooth to have it running with all 3 holes lined up (book doesn't mention that trick). Instead i left the pin and hole out of whack, and was lucky to keep center-line timing and a running engine.


VW obviously recognized this as a design flaw, because on the ALH they removed the keyway to allow the IP sprocket to float on its axis like the cam sprocket. On the ALH, you remove the IP locking pin after setting tension, not before. Having to loosen 3 or 4 bolts, plus possibly 4 injector lines, to allow the pump to rotate around the fixed sprocket -- that's just retarded.
 

turbodieseldyke

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Back to the OP's problem, here's a pic from Bentley for mounting an ALH tensioner.
It looks just as I believe the AHU tab slot is supposed to look -- about 1cm by 1cm. From OP's pics, it looked like someone dremel'd that slot to hell. I don't know if that would make the tab jump out, but it sure as hell didn't help hold it in place.
 

KLXD

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The book says to align all 3; lock cam & crank in place; remove IP pin; tension belt; rotate engine; check alignment .... and [paraphrased] "if cam and crank are good, but IP is slightly out of alignment, then loosen the pump to make it fit".

There is no "if". When the 3 pieces are aligned on a loose belt, and 2 of them are fixed in place, then the 3rd one is guaranteed to move when the belt is tensioned.

On the belt i changed last month, if i had followed the book and loosened the pump to make the IP pin fit the hole, i would have retarded it and probably had a no-start. And then i'd have to skip the pump one tooth to have it running with all 3 holes lined up (book doesn't mention that trick). Instead i left the pin and hole out of whack, and was lucky to keep center-line timing and a running engine.


VW obviously recognized this as a design flaw, because on the ALH they removed the keyway to allow the IP sprocket to float on its axis like the cam sprocket. On the ALH, you remove the IP locking pin after setting tension, not before. Having to loosen 3 or 4 bolts, plus possibly 4 injector lines, to allow the pump to rotate around the fixed sprocket -- that's just retarded.
Doesn't make sense. You can loosen the pump and turn it anywhere you want. The hole is in the pump mount not the pump itself. As one says follow the book unless it's wrong I just have to throw up my hands.

Still doesn't make it wrong about having the pin out for tensioning. Have to or the pump doesn't float to allow the belt to move. Like when you loosen the three sprocket bolts on the AHU.
 

KLXD

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While there's never any reason to allow slack between the pump and crank, sometimes when it's cold with a new belt and a fellow's not savy enough to line up the shipping bends in the best configuration...

But true, there probably isn't enough belt length to capture that much slack between the pump and crank. No doubt one would be miffed if he did.

While you didn't say it "holds the timing" you asked "how they intend to verify timing alignment if the pin is withdrawn". My misinterpretation I guess. The answer is he would see the hole in the mount behind the gear and that it's reasonably close.

The point is that it's an assembly of imperfect parts. The procedure allows for this by having everything in the belt path loose while tensioning the belt. Same reason for loosening the pump sprocket bolts when tensioning the belt on an ALH. You don't skip that step do you?

Your comment "but the degree of movement at the IP will be extremely small, but it will be there and it will make reinstalling the IP pin and checking for TDC at the crank a fudging issue as you bump things back and forth to find the right spot." makes my point.

It also concerns me. Turning the crank backwards should be avoided. Doing so puts tension on the slack side of the belt forcing the the tensioner to give a little as you try to turn the cam and pump backwards to where they were when you set it up. In other words to put that little bit of slack back in between the crank and pump.

I am sorry I offended you with my last comment in the earlier post. My intent was to say that one should follow the procedure unless there's a good reason not to. Like Turbo pointed out above.
 

Steve Addy

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While there's never any reason to allow slack between the pump and crank, sometimes when it's cold with a new belt and a fellow's not savy enough to line up the shipping bends in the best configuration...

But true, there probably isn't enough belt length to capture that much slack between the pump and crank. No doubt one would be miffed if he did.

While you didn't say it "holds the timing" you asked "how they intend to verify timing alignment if the pin is withdrawn". My misinterpretation I guess. The answer is he would see the hole in the mount behind the gear and that it's reasonably close.

The point is that it's an assembly of imperfect parts. The procedure allows for this by having everything in the belt path loose while tensioning the belt. Same reason for loosening the pump sprocket bolts when tensioning the belt on an ALH. You don't skip that step do you?

Your comment "but the degree of movement at the IP will be extremely small, but it will be there and it will make reinstalling the IP pin and checking for TDC at the crank a fudging issue as you bump things back and forth to find the right spot." makes my point.

It also concerns me. Turning the crank backwards should be avoided. Doing so puts tension on the slack side of the belt forcing the the tensioner to give a little as you try to turn the cam and pump backwards to where they were when you set it up. In other words to put that little bit of slack back in between the crank and pump.

I am sorry I offended you with my last comment in the earlier post. My intent was to say that one should follow the procedure unless there's a good reason not to. Like Turbo pointed out above.
I assume this was directed to me, so I'll respond, but I feel like we're beginning to beat a dead horse now so this will be short.

I have always worked from the point of view that you eliminate all slack between the crank sprocket and the IP sprocket when you install the belt. It has to be eliminated during install or the tensioning process will be faulty.

There have been times, with some brands of belts, where I have had to move the crank off TDC a fraction in order to get the belt engaged properly. Non-VW Gates belts come to mind with this. Most of the time I've been able to get the belt engaged properly by pushing down on the IP lock pin, but other times no. At any rate what I'm getting at is that I always assumed that it was first priority to eliminate any slack because of the reasons I mentioned in the prior post I made.

This process has served me well over the 3+ decades I've worked on these things and I assumed that everyone else worked from the same point, given that timing is so critical to these things.

And I don't know if you typed your above comment in error.

Stupid design? Idunno. You can adjust timing with the engine running. Can't do that with the AHU.
But you can and do adjust timing on the AHU while the engine is running, and that's not something you can do with the ALH, but I suspect that's what you meant to begin with.

I still believe that the process as set out by VW is semi-flawed in that it's unlikely that you will arrive after manual turning with the ability to reinstall the pin, and based on my prior comment I think it's not unrealistic to recognize it as such and decide for yourself whether you can live with the pin left in or not. And I agree with your point about only moving crank CW during the manual turning and pin / plate reinstall check.

My whole point was that I arrived at my conclusion using critical thinking, so I didn't think it was fair to make the claim that we follow a process we understand to be somewhat flawed and that demonstrated that we lacked critical thinking.

Steve
 

Steve Addy

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Back to the OP's problem, here's a pic from Bentley for mounting an ALH tensioner.
It looks just as I believe the AHU tab slot is supposed to look -- about 1cm by 1cm. From OP's pics, it looked like someone dremel'd that slot to hell. I don't know if that would make the tab jump out, but it sure as hell didn't help hold it in place.
I forgot to look at this on my spare engine in the shop. I will make a point to check next time down there.

EDIT: I decided that it would expedite the matter if I just looked online, part number 028109143H. Looks like that rectangular slot is normal. There are quite a few images of backing plates for 1Z / AHU and they all show the same size opening. So I don't think that contributed to the tensioner failure. I go back to the original theory that it was tensioned CCW.



Steve
 
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2004LB7

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I think they didn't get the tab in the slot when it was first tightened down. This bent the tab. Then I believe the nut wasn't torqued properly too and the tensioner tab was moving back and forth. If you look, there isn't any damage on the right side of the slot where the tab would ride against. If it was forced out of the slot then it would likely show a little damage. Maybe the whole tensioner rotated over along with the nut causing the nut to tighten up giving the impression it was torqued that way. My 2¢
 

Abacus

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I think they didn't get the tab in the slot when it was first tightened down. This bent the tab. Then I believe the nut wasn't torqued properly too and the tensioner tab was moving back and forth. If you look, there isn't any damage on the right side of the slot where the tab would ride against. If it was forced out of the slot then it would likely show a little damage. Maybe the whole tensioner rotated over along with the nut causing the nut to tighten up giving the impression it was torqued that way. My 2¢
I have to disagree, it was in the slot and you can see where it came out and gouged a groove to it’s resting location.

Yes, there are many locations that don't allow you to work on your car. We won't own one, but I know others that live in them.
 

2004LB7

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I have to disagree, it was in the slot and you can see where it came out and gouged a groove to it’s resting location.

Yes, there are many locations that don't allow you to work on your car. We won't own one, but I know others that live in them.
If you look closely at the slot, it doesn't look like the tensioner was forced out to me. See the attached photo. Also look at the tab itself. It is bent in the opposite direction one would think it would bend if it was forced out on that side of the slot. It is possible it was forced counterclockwise as some others suggest and the damage on that side of the slot shows some damage too. Once the tab was bent from being forced counterclockwise and now at the angle it is in now it would come out of the slot clockwise much easier. But this is all not going to happen unless the nut was loose enough to allow it to move
 

Steve Addy

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If you look closely at the slot, it doesn't look like the tensioner was forced out to me. See the attached photo. Also look at the tab itself. It is bent in the opposite direction one would think it would bend if it was forced out on that side of the slot. It is possible it was forced counterclockwise as some others suggest and the damage on that side of the slot shows some damage too. Once the tab was bent from being forced counterclockwise and now at the angle it is in now it would come out of the slot clockwise much easier. But this is all not going to happen unless the nut was loose enough to allow it to move
The other photo is better, it shows a clean backing plate but also the damage on the left side of the opening where the tab likely rested when it was tensioned CCW. At least that's what I believe anyway. I think all the damage on the right and the scraping along the backing plate was likely after the tab bent itself from being tensioned incorrectly.

If you notice on the tensioner the tab is bent in a way that made it easier to come out of the slot on the right side. My belief here is that the stress of being fixed in a direction that has no ability to accommodate changes in belt tension (i.e. the tensioner is only spring loaded in one direction, not the other) and as such it hammered at the tab until it bent, and once it was bent far enough to ride out over the backing plate it did so, despite the fact that the nut was tight. The fact that it only got as far as it did is probably what saved the engine from being killed

Engine starting and stopping, repeatedly, could have been the mechanism for the tensioners demise. Loading could have assisted in that also, the B4's don't have the clutched alternator pulley from the factory so abrupt changes (alternator charging, AC compressor operation, stopping and starting engine) can have adverse consequences, especially on a component wrongly installed.



The tab would not have bent in the direction it did unless it was installed incorrectly first and foremost. What happened after is just a consequence of that bad work.

At least this is the conclusion I came to anyway....

Now just waiting on updates about whether there's been any damage in the cylinder head etc.

Steve
 

CleverUserName

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I have a spare engine rolling around the shop on a cart with no TB on it, I'll see if it's consistent with his.


Further, ÜRO doesn't mark all the products they repackage either, so the fact that it doesn't possess the ÜRO moniker anywhere is not surprising. ÜRO doesn't make anything so I have always considered them to be a bottom of the barrel Beck/Arnley in many respects.

This is not a tensioner I would use unless I had no other option. In fact I would trust a used Litens tensioner that had a good quality bearing before I wasted money on a ÜRO tensioner.


Steve
Is Beck/Arnley low quality? Not in my experience. I’ve gotten OEM parts in OE packaging stuffed in BA labeled boxes.

The CJAA water pump I recently got was a GEBA metal impeller pump made in Germany and was sold in a Beck Arnley box.

If given the choice, I’ve always gotten BA parts first and never been disappointed.
 

Abacus

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That the tab is bent in the opposite direction is of no consequence since it would bend back and forth with the hammering it took due to being tensioned incorrectly. It clearly hammered back and forth in the slot so I don't think it was outside that when it was installed.

BA parts are hit or miss, I've had some that are OEM in their packaging and some that are junk. It's a roll of the dice and if the price is low enough I'll take the gamble but I'd rather pay full price for a known top quality part since it's cheaper in the long run.
 

2004LB7

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The other photo is better, it shows a clean backing plate but also the damage on the left side of the opening where the tab likely rested when it was tensioned CCW. At least that's what I believe anyway. I think all the damage on the right and the scraping along the backing plate was likely after the tab bent itself from being tensioned incorrectly.

If you notice on the tensioner the tab is bent in a way that made it easier to come out of the slot on the right side. My belief here is that the stress of being fixed in a direction that has no ability to accommodate changes in belt tension (i.e. the tensioner is only spring loaded in one direction, not the other) and as such it hammered at the tab until it bent, and once it was bent far enough to ride out over the backing plate it did so, despite the fact that the nut was tight. The fact that it only got as far as it did is probably what saved the engine from being killed

Engine starting and stopping, repeatedly, could have been the mechanism for the tensioners demise. Loading could have assisted in that also, the B4's don't have the clutched alternator pulley from the factory so abrupt changes (alternator charging, AC compressor operation, stopping and starting engine) can have adverse consequences, especially on a component wrongly installed.



The tab would not have bent in the direction it did unless it was installed incorrectly first and foremost. What happened after is just a consequence of that bad work.

At least this is the conclusion I came to anyway....

Now just waiting on updates about whether there's been any damage in the cylinder head etc.

Steve
That's kinda what I was trying to say but you said it better
 

Steve Addy

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That the tab is bent in the opposite direction is of no consequence since it would bend back and forth with the hammering it took due to being tensioned incorrectly. It clearly hammered back and forth in the slot so I don't think it was outside that when it was installed.

BA parts are hit or miss, I've had some that are OEM in their packaging and some that are junk. It's a roll of the dice and if the price is low enough I'll take the gamble but I'd rather pay full price for a known top quality part since it's cheaper in the long run.
We don't (and probably can't) know for sure that the force was equal on the tab in both directions. I think if it had been the tab would have broken from fatigue rather than just bent in the one direction. And it doesn't appear to me that it was being bent back and forth either.

The question of what happens when you 'tension' in a CCW manner is what matters here, and I believe that you're actually lessoning the amount of spring loading on the tensioner when you do it CCW. But without doing a test I won't know for sure and one does not want to destroy a new tensioner to try this either.

It just seems to reason that the action would not have been equal and opposite (i.e. same from both sides) if you unload the tensioner spring by doing it in a CCW manner.

However, this is just speculation on my part, but I'd be interested in knowing what went on in there.

Steve
 

Benjamis

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Yea, by the looks of it I think that they overtensioned it CCW way too hard, trying to get the alignment tabs to line up, which gouged the left side of the notch and bent the arm, and eventually it popped out the right side. I did notice while messing around with the old tensioner that if the unit moves CW it will tighten the nut, so there is the possibility that the nut was not torqued to spec, and when the arm popped out of the notch, it did indeed tighten the nut to the proper torque of 15 lbs, but either way, with the nut torqed to 17 lbs, the arm could move. Maybe the arm was already popped out last year, if you see the scratch, there is a divet only about 1/3 of the way, which maybe caught the arm for a while, and was enough to give the occasional misfires I experienced for a spell. I didn't have VCDS last year though, but got it a few months ago, and last time I checked about 2 months ago, the timing was dead center in the chart on VCDS, and it ran like a dream. I suppose we can speculate indefinitely and maybe never know, but once again, I really appreciate all the info and speculation and discussion.

This all got me in a busy time, the parts finally came end of last week, and I don't think I'll get to it until this coming weekend, but it's nice to see the Litens tensioner, it's clearly a lot nicer to look at, The Hans tensioner doesn't seem cheap at first, but yea they had to cut corners.

According to this http://www.litensaftermarket.com/fi...enspanner/VW_1.9L_TDI_installation_notice.pdf
I was sent the obsolete tensioner with brown seal, part number 028 109 243F. Manufactured 32nd week of 05. Is this of any concern? It's clearly brand new though and has the VW stamp, and the arm is nice and straight. NTN bearing. Looks to be of quality craftsmanship.

I got a VW Gates belt and Ina roller with it, from Cascade German for $80. It's a nice looking belt.
 

Steve Addy

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97 Mk3
...
According to this http://www.litensaftermarket.com/fi...enspanner/VW_1.9L_TDI_installation_notice.pdf
I was sent the obsolete tensioner with brown seal, part number 028 109 243F. Manufactured 32nd week of 05. Is this of any concern? It's clearly brand new though and has the VW stamp, and the arm is nice and straight. NTN bearing. Looks to be of quality craftsmanship.

I got a VW Gates belt and Ina roller with it, from Cascade German for $80. It's a nice looking belt.
Yeah you don't need to worry about that, I'm not sure why they send that out TBH, the part numbers they reference in that document are for the ALH engine and not the 1Z / AHU. This has come up before and it was quashed back then.

If you check the pdf it says 038109243G and that's a late ALH tensioner, and none of the supersessions for the ...G part number include the 028109243F. If you compare the two tensioners physically there's a pretty big difference in the offset from the block, they cannot be interchanged unless someone is looking to destroy an engine for some reason.

The same goes for the Goodyear (Conti) part number 48008, it applies to ALH engine and not 1Z / AHU. The correct Conti number for 1Z / AHU is 48006. I have no idea what the current Goodyear part number is for 1Z / AHU, I think they changed that up a while back and it doesn't follow Continental anymore, it might be T43006 or something like that though.

At any rate, ignore that pdf completely and discard it, it doesn't apply!

Steve
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
The question of what happens when you 'tension' in a CCW manner is what matters here, and I believe that you're actually lessoning the amount of spring loading on the tensioner when you do it CCW. But without doing a test I won't know for sure and one does not want to destroy a new tensioner to try this either.
I tensioned the wrong way, once. I realized my mistake, prior to starting the engine. I pulled it off the car and it didn’t feel right, comparing it to a new one. If I remember correctly, it made a strange noise, as the spring was rewinding. It went in the trash.... wasn’t really happy about that, but oh well...

-Todd
 

Steve Addy

Top Post Dawg
Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
I tensioned the wrong way, once. I realized my mistake, prior to starting the engine. I pulled it off the car and it didn’t feel right, comparing it to a new one. If I remember correctly, it made a strange noise, as the spring was rewinding. It went in the trash.... wasn’t really happy about that, but oh well...

-Todd
Interesting, I have never done it so I don't know what to expect, but I have a used tensioner on the shelf from the rotten green jetta car that I might just install and tension CCW with an old belt on my spare engine just to see what happens. It's not going to get used on anything anyway so this is a good project for it!

Steve
 

Benjamis

Veteran Member
Joined
Jan 17, 2021
Location
Due east of Cincinnati, Ohio
TDI
1996 B4V 1Z 318k
Ok, so I got to doing the timing belt finally. Was easier than I thought it would be. For me, the IP sprocket was still perfect after tensioning, but the cam seemed to go a bit retarded on the cam lock. I rotated the engine via the crank bolt 2 full turns and saw the tensioner alignment tabs were off. So according to this:
http://www.litensaftermarket.com/fi...enspanner/VW_1.9L_TDI_installation_notice.pdf
I retensioned the tensioner, perhaps against the advise of some on this forum, but it seemed proper. I rotated the engine again 2 turns and the alignment tabs stayed lined up, so I moved on.
I decided to crank the engine to check for proper belt tracking, as it seemed before that the belt was riding the edge of the pulleys away from the engine. The engine started instantaneously, which I don't think has ever happened. Not even a split second of cranking. It was in the upper 80s and sunny, which helped, but either way, I was impressed. I turned it off after 1 second and saw the belt tracking was good, so assembled everything and test drove, hooked up VCDS and timing was in between dead center and the top line, so I called it good without adjusting.
It all seemed too easy. Life was good, she rode like a dream once again. Time to start another thread.
https://forums.tdiclub.com/index.ph...4-miles-with-no-effect-on-performance.515701/
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
Nice to get it running like it should.

If it makes you feel better, some more of that critical thinking tells me that tensioning it two or three or twenty times is nothing compared to the bouncing around it does while running.
 
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