Car died today 185 miles from my tools

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
With no history on the tb, that would have been one of the first things I’d have done, for peace of mind. Oh well, what’s done is done...

Not good news about #7. If you’re trying to avoid pulling the head, you could always do a leak down test, but I have a feeling you know there’s going to be an issue.

With an engine with that much mileage, I’d probably just install a known good head from a partout, if the crank looks good and you plan on keeping the car.

-Todd
 

bigred177

Veteran Member
Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
You could flat tow it to El Paso and back twice.

It won't fix anything but you would be able to show 500K. :)

I know. Not helpful.

Are you saying that you can't turn the engine over with the cam out? If so, you certainly need to pull the head to find out why. Is that #7 valve lower than the others? Can you pull the valve stem up?

It certainly sounds like something is amiss in the head - most likely the valve. Sucks to be so close to 500K and have this happen.

Edit: The thing that amazes me the most is the corrosion on the tensioner after sitting for just a few months in Texas. Hmmm.
You have no idea. The thing that upsets me most isn't that it broke, it's that I won't make 500k.

It is lower than the others, had a hard time getting the lifter out. I can't pull it up. She stuck.

It's been uncharacteristically rainy here this year. Plus, Austin is nice and humid.
 

bigred177

Veteran Member
Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
With no history on the tb, that would have been one of the first things I’d have done, for peace of mind. Oh well, what’s done is done...

Not good news about #7. If you’re trying to avoid pulling the head, you could always do a leak down test, but I have a feeling you know there’s going to be an issue.

With an engine with that much mileage, I’d probably just install a known good head from a partout, if the crank looks good and you plan on keeping the car.

-Todd
Yea, hindsight and all that. It was fairly recent and from a dealer. I should have known better. I will pull the head tomorrow and assess, with many pictures and y'all's guidance. I do plan on keeping it. What is your suggestion for tracking down a head?

Luckily I still have my 97 Jetta TDI. She's just a baby at 250k. I'd be broke from fuel expenses without my VW diesels
 

bigred177

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Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
Here is the tensioner I removed from mine 2 weeks ago.
Thankfully it had not caused a slipped belt.
Did you do yours yourself or did you have it done?

Does our ECU log mileage? I'm looking at a donor car but I think the mileage is wrong. I know the newer ones do but I thought I saw somewhere ours didn't.
 

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
So do we know for a definitive fact that this is a failure of the tensioner that caused this, or was it more of excessive wear on the belt, when the valves hit it causes it to bend?

I dont see how this part can fail like this but i have seen a few threads about it and a supposed upgrade part.

What causes this failure? is it the cause or an effect?

To me, this looks like a result of a failed or jumped belt that gets excessive tension put on it from valve contact and that this does not cause the damage but is a external sign of the damage within as a result.
 

bigred177

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Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
So do we know for a definitive fact that this is a failure of the tensioner that caused this, or was it more of excessive wear on the belt, when the valves hit it causes it to bend?

I dont see how this part can fail like this but i have seen a few threads about it and a supposed upgrade part.

What causes this failure? is it the cause or an effect?

To me, this looks like a result of a failed or jumped belt that gets excessive tension put on it from valve contact and that this does not cause the damage but is a external sign of the damage within as a result.
I don't know anything for a definitive fact. I'm just a wrench monkey, you guys are the pros. I'm just posting pictures as I find broken things.

What I do know is that this belt and pulley had less than 25k on it and is still in tact with no missing teeth. I know that: I was merging on to the highway when the car felt like it was losing power in 5th. The engine was turning with no noises or vibrations, just winding down. When I got slow enough I pushed the clutch in to shift to 4th and the car instantly dropped from ~1800rpm to 0. I left the clutch in and coasted to the shoulder. I tried one time to start it and it made no effort to start.
 

Yblocker

Veteran Member
Joined
Sep 1, 2010
Location
Oakland, CA
TDI
1997 Passat
Did you do yours yourself or did you have it done?.
I did the belt etc. using proper methods. Car has been running great. I can see how the catastrophic damage that occurred to your engine might bend that locating tab, but I'm at a loss as to why mine bent.
 

Steve Addy

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Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
I'm getting nervous about these Litens tensioners now with this one and the earlier one that did the same thing.

I'm especially concerned with the production date of 2013 on this recent one.

Steve
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Yea, bad pic. It's pieces of piston.





The scoring is deep enough to catch my nail on.
Thanks for the additional pictures. It almost looks like the piston was welded at TDC and the chunk tore off on the downstroke. I can't figure out how that could have happened. Maybe that injector failed and things got hot in there, expanded the piston, seized it and on subsequent rotations, it tore off. I say this because there is no soot on the piece.

I'm just guessing based on pictures and a description of the events.

Have you come up with a game plan?
 

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Thanks for the additional pictures. It almost looks like the piston was welded at TDC and the chunk tore off on the downstroke. I can't figure out how that could have happened. Maybe that injector failed and things got hot in there, expanded the piston, seized it and on subsequent rotations, it tore off. I say this because there is no soot on the piece.
I'm just guessing based on pictures and a description of the events.
Have you come up with a game plan?
No, that’s 100% piston ring gap closed. AKA lack of oil or cooling or to hot EGT's. If you get chips of chunks off the side of the piston on the top like this, I guarantee you that it was from the piston ring closing up the gap and when it had no more room it expands upwards like a pringle or piece of bacon causing a part to break off. This is what the cause was. Something caused the ring to close up, to much heat, this caused a chunk to break off and hit the valves causing the cam to not want to rotate vs the crank causing the belt to skip and put too much force on the tensioner causing it to bend.

That tensioner was a side effect of too much engine temps for some reason.
Pull the oil pan and the oil pump and inspect.

This is not the first time I have seen that damage and only one thing causes it. RING GAP
I usually see this from too much NOS though.
 

KLXD

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Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
Here is the tensioner I removed from mine 2 weeks ago.
Thankfully it had not caused a slipped belt.
The thing is, once the tensioner nut is tightened the tab doesn't do anything. It's only there for the spring to act against as the belt is tensioned.

It still has the original preload on it but there's no dynamic force acting on it.

If the bearing were to seize there might be enough force to overcome the friction applied by the nut and cause what is pictured but no one is reporting a locked up bearing.

I'd say it was installed that way except for the deformed pulley. It would either not rotate or show some wear on the edge.

A momentary lock up seems unlikely but it's the only thing I can think of that would splain the condition.
 
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KLXD

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Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
Going to have to sharpen my pencil and find a napkin to compute how hot the ring would have to be to expand enough to close up the gap and then buckle enough to cause enough lateral force to break off a chunk of piston.

If it did it doesn't 100% splain the apparent piece of piston stuck at the top of the bore.
 
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Yblocker

Veteran Member
Joined
Sep 1, 2010
Location
Oakland, CA
TDI
1997 Passat
The thing is, once the tensioner nut is tightened the tab doesn't do anything. It's only there for the spring to act against as the belt is tensioned.

It still has the original preload on it but there's no dynamic force acting on it.

If the bearing were to seize there might be enough force to overcome the friction applied by the nut and cause what is pictured but no one is reporting a locked up bearing.

I'd say it was installed that way except for the deformed pulley. It would either not rotate or show some wear on the edge.

A momentary lock up seems unlikely but it's the only thing I can think of that would splain the condition.
I realize we are kind of covering two separate topics here, so I won't go on and on about it as I don't want to hijack the OPs thread. I will say that the bearing on the roller was smooth, and there does not appear to be any wear on the shoulder of the pulley indicating that it had been run this way. It was new and in good shape when I bought and installed it 60,000 miles ago. When I took this apart last week, I did not use a tool to de-tension the tensioner; I think I just backed off the nut which should de-tension thngs. Then I removed the cam sproket and pulled it all out of there. That's when I noticed the bent tab.
 

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Going to have to sharpen my pencil and find a napkin to compute how hot the ring would have to be to expand enough to close up the gap and then buckle enough to cause enough lateral force to break off a chunk of piston.

If it did it doesn't 100% splain the apparent piece of piston stuck at the top of the bore.
It does, I’ve never seen it on a DIESEL, like I said, and I’ve only seen it from NOS getting too hot. If the piston gets too hot and the rings have nowhere to go well it’s going to pop off a bit of the piston when it expands upwards in the least plain of resistance, at those temps it could weld its self on. I think it happened like this.

Engine got oil starved, see all that scoring, that’s oil starved.
Piston got too hot causing a lock up scenario.
Once OP shifted it stopped rotating and that piston was near or at TDC when it stopped moving.
The buildup of heat from heat soak finished it off, was shredded from ring damaged and when it rotated again it broke off.

a chip off like that was defiantly due to ring damage gap closure but I don’t think it came off when running as I see no damage to the top of the head or the piston top from impact when running.


As for the tensioner, it defiantly failed at the time of incident and possibly after it seized. There are no wear marks where it’s making contact and where the belt is. So it could not have rotated at all with this damage. This means it was forced over like that when the belt got enough tension on it from the locked up piston situation.


http://www.superchevy.com/how-to/148-0303-small-block-nitrous-blow-up/




http://garage.grumpysperformance.com/index.php?threads/detonation-damage.2883/



https://www.youtube.com/watch?v=AScojLj139A&t=996s
Jump to 15:20 for the carnage and a good explanation of why gas engines need more ring gap for high levels of NOS. The thing with a diesel is you dont need the gap for NOS it cools down the fuel burning and does not heat up the engine as much as a gas, too much NOS in a diesel will put out the flame so to say.
Now this happened in this video from too much heat from NOS but i suspect, from the scoring that this was oil starved cause.

I would say this looks the same 100% as OP's damage.
Caused by ring gap damage from too much heat. BUT WHY? thats the issue here. OP needs to take the lower half apart and inspect the oil pump and squirts, piston pins and crank. I highly suspect carnage to be evident in the oil pump and on the wrist pin
 
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bigred177

Veteran Member
Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
Thanks for the additional pictures. It almost looks like the piston was welded at TDC and the chunk tore off on the downstroke. I can't figure out how that could have happened. Maybe that injector failed and things got hot in there, expanded the piston, seized it and on subsequent rotations, it tore off. I say this because there is no soot on the piece.
I'm just guessing based on pictures and a description of the events.
Have you come up with a game plan?
Not sure. I still have my Jetta so I'm not in a huge rush. From the scoring I've kind of decided to write this block off. I don't know if it's worth rebuilding. There is a 130k mile AHU in Dallas with an ECU (current one is the BK ECU) for $1k I thought about going to pick up and put in this body, but I'm still stuck on the windshield rust. I found another B4V for $3500 with a supposed rebuilt engine. Might call on that one and either sell the bones of this car or keep a parts car.
 

bigred177

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Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
It does, I’ve never seen it on a DIESEL, like I said, and I’ve only seen it from NOS getting too hot. If the piston gets too hot and the rings have nowhere to go well it’s going to pop off a bit of the piston when it expands upwards in the least plain of resistance, at those temps it could weld its self on. I think it happened like this.

Engine got oil starved, see all that scoring, that’s oil starved.
Piston got too hot causing a lock up scenario.
Once OP shifted it stopped rotating and that piston was near or at TDC when it stopped moving.
The buildup of heat from heat soak finished it off, was shredded from ring damaged and when it rotated again it broke off.

a chip off like that was defiantly due to ring damage gap closure but I don’t think it came off when running as I see no damage to the top of the head or the piston top from impact when running.


As for the tensioner, it defiantly failed at the time of incident and possibly after it seized. There are no wear marks where it’s making contact and where the belt is. So it could not have rotated at all with this damage. This means it was forced over like that when the belt got enough tension on it from the locked up piston situation.


http://www.superchevy.com/how-to/148-0303-small-block-nitrous-blow-up/




http://garage.grumpysperformance.com/index.php?threads/detonation-damage.2883/



https://www.youtube.com/watch?v=AScojLj139A&t=996s
Jump to 15:20 for the carnage and a good explanation of why gas engines need more ring gap for high levels of NOS. The thing with a diesel is you dont need the gap for NOS it cools down the fuel burning and does not heat up the engine as much as a gas, too much NOS in a diesel will put out the flame so to say.
Now this happened in this video from too much heat from NOS but i suspect, from the scoring that this was oil starved cause.

I would say this looks the same 100% as OP's damage.
Caused by ring gap damage from too much heat. BUT WHY? thats the issue here. OP needs to take the lower half apart and inspect the oil pump and squirts, piston pins and crank. I highly suspect carnage to be evident in the oil pump and on the wrist pin

That's extremely interesting. It'll be a while, but I could probably pull the bottom off and check things out. This car never gave an indication of any problem prior to this failure. No injector issues, oil pressure issues, nothing.
 

bigred177

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Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
I did the belt etc. using proper methods. Car has been running great. I can see how the catastrophic damage that occurred to your engine might bend that locating tab, but I'm at a loss as to why mine bent.
The reason I ask is because I was talking with a VW mechanic friend of mine and he's seen before where a mechanic will miss the hole for that tab and bend it. So if you had someone else do it that would have been my thought.
 

Yblocker

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Joined
Sep 1, 2010
Location
Oakland, CA
TDI
1997 Passat
The reason I ask is because I was talking with a VW mechanic friend of mine and he's seen before where a mechanic will miss the hole for that tab and bend it. So if you had someone else do it that would have been my thought.
I get it. No way that happened though. I agree with your plan to re-power with a different engine. It will be cheaper and more appropriate for your car.
 

whitedog

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Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
No, that’s 100% piston ring gap closed. AKA lack of oil or cooling or to hot EGT's. If you get chips of chunks off the side of the piston on the top like this, I guarantee you that it was from the piston ring closing up the gap and when it had no more room it expands upwards like a pringle or piece of bacon causing a part to break off. This is what the cause was. Something caused the ring to close up, to much heat, this caused a chunk to break off and hit the valves causing the cam to not want to rotate vs the crank causing the belt to skip and put too much force on the tensioner causing it to bend.
That tensioner was a side effect of too much engine temps for some reason.
Pull the oil pan and the oil pump and inspect.
This is not the first time I have seen that damage and only one thing causes it. RING GAP
I usually see this from too much NOS though.
There has been no mention of other cylinders scored and the tiny bit of #3 that we can see doesn't appear to have any scoring. So my best guess about the scoring is a plugged or damaged squirter.
 

Mongler98

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Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
There has been no mention of other cylinders scored and the tiny bit of #3 that we can see doesn't appear to have any scoring. So my best guess about the scoring is a plugged or damaged squirter.

my thoughts exactly.
I would love to know exactly the real true cause of this. I am just speculating with my past experience and the wisdom from other blogs and videos i have seen. I'm fairly confident in my conclusion but you never know.

Why would a squirter fail?
My hunch is that OP used a oil filter that was defective. Purolator oil filters had a recall last year for rips and damages in the filter paper, it was the year i started using mobile one oil filters as I'm not going to risk it. Maybe that might be the issue? i don't know.

chunk of paper or crud got into the passage way and like a calcium covered shower head, the oil was not shooting out directly or at all.
 

bigred177

Veteran Member
Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
I was going to take some pictures of the other cylinders but it got dark on me. None of the other cylinders have any scoring on them.

I'm curious on y'all's thoughts. This is the only blemish on this car. I'm still considering putting a new engine in it; this is my only hold up though.







 

Abacus

That helpful B4 guy
Joined
Nov 10, 2007
Location
Relocated from Maine to Dewey, AZ
TDI
Only the B4V left
Yeah, that's pretty major, but not a bad fix with the windshield out.

That sucks about the engine, if you were closer I have an AHU block I'd throw your way for nothing.

bigred177 said:
The thing that upsets me most isn't that it broke, it's that I won't make 500k.
Same here. My own B4 made it to 454K when the engine went, I think a rod bent. I'm going to have a look when it stops snowing. I have some spare rods and will probably rebuild it but we don't need 4 cars so it'll be up on the auction block when I'm done. I JUST repaired the floorboards in it as well, which sucks, and I won't part it out.
 

bigred177

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Joined
Aug 23, 2011
Location
Austin, TX
TDI
97 Jetta
Yeah, that's pretty major, but not a bad fix with the windshield out.

That sucks about the engine, if you were closer I have an AHU block I'd throw your way for nothing.



Same here. My own B4 made it to 454K when the engine went, I think a rod bent. I'm going to have a look when it stops snowing. I have some spare rods and will probably rebuild it but we don't need 4 cars so it'll be up on the auction block when I'm done. I JUST repaired the floorboards in it as well, which sucks, and I won't part it out.
I appreciate the thought. Thank you.

I'm jealous of your engines in your signature. I need that B4 one when you get it going again ;)
 
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