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Discussion Starter #1
Several 130 or AXD and 174 or AXE motors have had 'Catastrophic failure' documented on this forum,it would be interesting to see if it is a repeating scenario.
It starts with a misfire,progresses to difficult starting with pointing uphill/downhill sometimes making a difference, and ends with a runaway engine dieseling or just non start and diesel fuel in sump oil.:eek:
A denmark VW tech has posted that there is a cracking problem on #3 cylinder in the cylinder head. I:
Whilst rereading http://pierro777.free.fr/DOCVAG/2.5_TDI.pdf the drawing 305_020 shows the close proximity of the pressurized fuel gallery to the inlet port.
If these two were to connect would that cause these failures? :confused:
 

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my head is OK but the bottom end blew up, in teh manner as you described - 3 holes in the block

65000 miles........- and VW say they know of no such problems with the AXD / AXE engine

can we do a survey of us with similar then it can be used to try and argue the case with VW

Ross
 

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Discussion Starter #3
This is a problem they are aware of but not broadcasting......
Thanks for the following from a vw tech in europe......

Hello. I am technical advisor at a dealership in Denmark.
I myself have a 2.5 which could not start very well when it was parked with its nose up, but no problem pointing down.
It mixed fuel in the oil.
I've tried changing the tandem pump, 2 pd injectors, all O-rings in all injectors twice. It didn't help.
Then I tried to put 1.2 bar pressure in the fuel rail, and it lost pressure .
It turned out there was a leak from the fuel duct over to an oil duct in the cylinder head.
I changed the cylinder head and now it works.
The small scratches in the pd injector holes, means nothing, it is between cyl 3 and 4 it is wrong.
Hope you can use this .. By the way. It´s no problem to change tandempump or cylinderhead while the engine is in the van, it takes about 6 hours to change the cylinderhead. But the cylinderhead from VW only comes with all the pd-elements :eek:
 

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Hi dvdfrost,pls see my update on my van on festa thread, original symptoms [on page 7 of that thread] just found crack from no 3 injector bore, but all my symptoms same as being listed. Hope this helps
 

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Discussion Starter #5
I took the liberty of posting DrFeelgood find here from the festa thread as I think you have got to the root cause of this common problem:

T5 Post Icon Re: update on my unwell van 2.5 174
Hi guys, just an update on my van [see page 7 of this thread]This refers to Festas' Unwell van thread its been laid up since christmas, as i have only just been able to get the time to look at it. Stripped it today and when pressure testing the fuel rail it would not hold pressure,i could also hear air escaping near no 3 injector.
Blanked return line to filter and could get 1 bar pressure but quickly dropped off . Then could see diesel pooling in front of no3 injector. Removed injector no 3 and found a hairline crack at the back of the injector bore staring from inside the bore [between flow and return ports] and working its way back towards the rear of the head.
It would appear that my staring problems were due to the loss of fuel pressure as the crack started in the injector bore and allowed a passage from flow to retun and the diesel in the oil as the crack extended and opened under max pressure upto 9 bar allowing diesel to mix with the oil as next to no3 there is an oil return to the sump.
Also i always had a slight rough spot approx 1.5k rpm.......All sounding familiar. Have taken some photos on my iphone just need to work out how to post them. I have ordered the locking tools and should have them friday. Does anyone have the elsawin sequence and torque settings as my copy has gone u/s since i last used it, plus any idea on how to use the locking tools ?

Any help greatfully appreciated will keep you posted i just love my van and cannot wait to to get it fixed an smokin around again
 

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Discussion Starter #6
How do you get Iphone photos to size down to fit on this forum?
I have photos of my injectors I would like to post.
 

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:eek:Just a sanity check I have a 2.5tdi 2003 T4 88BHP though re - mapped, its only done 79K miles. Does my engine fall into this category or is something that went into the T5's .

Just concerned

Thanks
 

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I have been thinking about this fault, and wondering if a piece of metal tubing could be pressed firmly into the bore to form a seal over the crack. Has anyone else thought about this or other ways to provide a simple and quick fix?

Brian
 

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This is a problem they are aware of but not broadcasting......
Thanks for the following from a vw tech in europe......

Hello. I am technical advisor at a dealership in Denmark.
I myself have a 2.5 which could not start very well when it was parked with its nose up, but no problem pointing down.
It mixed fuel in the oil.
I've tried changing the tandem pump, 2 pd injectors, all O-rings in all injectors twice. It didn't help.
Then I tried to put 1.2 bar pressure in the fuel rail, and it lost pressure .
It turned out there was a leak from the fuel duct over to an oil duct in the cylinder head.
I changed the cylinder head and now it works.
The small scratches in the pd injector holes, means nothing, it is between cyl 3 and 4 it is wrong.
Hope you can use this .. By the way. It´s no problem to change tandempump or cylinderhead while the engine is in the van, it takes about 6 hours to change the cylinderhead. But the cylinderhead from VW only comes with all the pd-elements :eek:
I recently purchased a 2.5 128kW Van with 138000km. I had exactly the same problems, in fact, I've owned the vehicle 5 months and haven't done more than 200kms!! With the assistance of a VW mechanic we systematically have gone through everything and could not find anything wrong. Eventually the mechanic had a suspicion of diesel in the sump and we investigated that. We discovered that where the injectors fit into the cylinder head, there were huge ridges which we believe allow the diesel fuel to leak past and mix with the engine oil. We understand that the ridges are caused by the injector pinch bolt loosening slightly (vibration?). The cost of a new cylinder head in South Africa is R107000-00!!! I didn't pay this for the Van!!! Fortunately through my years of business association I have a mate that owns a very reputable engineering shop. I left the head with him and he did a fantastic job of boring the head and making new press fit inserts and then drilled the holes for the fuel line. It is an absolute work of art and we shall see how it performs in the next week or so when we assemble it.

If loose injectors are the cause of this problem, perhaps owners of these vehicles should double check the tightness of the pinch bolts - because VW agents DON'T in any service and deny any liability that it is a problem.
 

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Discussion Starter #12
This idea of harder sleeves may be a good mod for the future as this problem will not go away and the filings or swarf from the fretting of injector against head get washed away by the fuel into the injectors blocking the orifices causing misfires.T:
 

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I recently purchased a 2.5 128kW Van with 138000km. I had exactly the same problems, in fact, I've owned the vehicle 5 months and haven't done more than 200kms!! With the assistance of a VW mechanic we systematically have gone through everything and could not find anything wrong. Eventually the mechanic had a suspicion of diesel in the sump and we investigated that. We discovered that where the injectors fit into the cylinder head, there were huge ridges which we believe allow the diesel fuel to leak past and mix with the engine oil. We understand that the ridges are caused by the injector pinch bolt loosening slightly (vibration?). The cost of a new cylinder head in South Africa is R107000-00!!! I didn't pay this for the Van!!! Fortunately through my years of business association I have a mate that owns a very reputable engineering shop. I left the head with him and he did a fantastic job of boring the head and making new press fit inserts and then drilled the holes for the fuel line. It is an absolute work of art and we shall see how it performs in the next week or so when we assemble it.

If loose injectors are the cause of this problem, perhaps owners of these vehicles should double check the tightness of the pinch bolts - because VW agents DON'T in any service and deny any liability that it is a problem.
This thread makes for some scary reading!!!
Did you manage to get some photo's of the head before and after you had the work done by your Engineering friend?
 

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Discussion Starter #15
Great excuse for a holiday to South Africa!T:,
wonder what is excess baggage cost for a cylinder head?I:
 

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I recently purchased a 2.5 128kW Van with 138000km. I had exactly the same problems, in fact, I've owned the vehicle 5 months and haven't done more than 200kms!! With the assistance of a VW mechanic we systematically have gone through everything and could not find anything wrong. Eventually the mechanic had a suspicion of diesel in the sump and we investigated that. We discovered that where the injectors fit into the cylinder head, there were huge ridges which we believe allow the diesel fuel to leak past and mix with the engine oil. We understand that the ridges are caused by the injector pinch bolt loosening slightly (vibration?). The cost of a new cylinder head in South Africa is R107000-00!!! I didn't pay this for the Van!!! Fortunately through my years of business association I have a mate that owns a very reputable engineering shop. I left the head with him and he did a fantastic job of boring the head and making new press fit inserts and then drilled the holes for the fuel line. It is an absolute work of art and we shall see how it performs in the next week or so when we assemble it.

If loose injectors are the cause of this problem, perhaps owners of these vehicles should double check the tightness of the pinch bolts - because VW agents DON'T in any service and deny any liability that it is a problem.

Any updates on the above??

Cheers
Andy
 

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Discussion Starter #17
Interesting that you can't buy a bare head from VW,it come with injectors already in.
would that be because they are concerned about injector to head fretting and cracking?
At £3000 for the head assembly or 5k for engine it is going to remove these vehicles from the worlds car parc pretty quick once they get older due to uneconomical repair.
 

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Interesting that you can't buy a bare head from VW,it come with injectors already in.
would that be because they are concerned about injector to head fretting and cracking?
At £3000 for the head assembly or 5k for engine it is going to remove these vehicles from the worlds car parc pretty quick once they get older due to uneconomical repair.
I managed to source a bare head for £950 ish :)
 

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Discussion Starter #19
Was your new head a different casting or a different design in anyway?
Where did you get it ?
Was it a one off or would they have more?
 

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This thread makes for some scary reading!!!
Did you manage to get some photo's of the head before and after you had the work done by your Engineering friend?
Herewith my before and after photos of the injector bore re-bushing. I understand that this thread is about the heads cracking, but these injector bores wearing ridges seems to be a very common problem as well.

Injector bore prior to re-bushing showing the deep ridges


Injector bore re-bushed_1


Injector bore re-bushed_2
 
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