Page 7 of 11 FirstFirst ... 56789 ... LastLast
Results 61 to 70 of 109

Thread: 2.7 and 3.0 Td V6 Crankshaft Bearing Failure known manufacturing fault

  1. #61
    Join Date
    Sep 2014
    Location
    Baldivis WA
    Posts
    2,293
    Total Downloaded
    0
    The fitting centres I saw during my visit to the Solihull factory last March are pretty much exactly like in those mega factory shows. I saw the final Assembly line where items like suspension and complete engines are fitted to the chassis. The one line assembled D5, jaguar f-pace and range rover, including the SVR. All the bolts for the suspension linkages would be tightened (torqued or tensioned, depends on the application) in one machine operation whilst held in a jig. All torques are computer controlled, and random checks are taken. A green or red light on the console would tell the operator that the torque is good or not, before he presses the button to release the assembly from the jig.

    I don't think it would take much of a computer programming error to have the incorrect torque value provided to the tool, or a tool being out of calibration to cause an error.

    I tend to think now that the issue re these crank failures is either an assembly issue, so incorrect torque settings, or a design issue (oil port location or incorrect clearances or the missing locating tab on the bearing shell for example)

    A bearing shell failure would cause an instant oil pressure drop as the hydrodynamic oil film would instantly fail, leading to metal to metal contact and a fused bearing as a result. The force of the other pistons would cause the crank to then fail at the weakest point, typically where the big end meets the side plates.

    So monitoring oil pressure at the crank would be a good starting point. Just not sure if you could isolate the oil feed into the crank galleries?

    Just my 2c

  2. #62
    BradC is offline Super Moderator
    No one of consequence
    Supporter
    Join Date
    Mar 2018
    Location
    Perth (near Malaga)
    Posts
    3,546
    Total Downloaded
    0
    Quote Originally Posted by PerthDisco View Post
    But this occurring continuously over 10 years and different engine types seems crazy.
    I agree completely, but there has been more than one post on the Disco3/4 forums in the UK along the lines of "I pulled the sump and some of the main bearing cap bolts were loose". Now, consequence of assembly, design or act of god. The result would wind up the same.

    Something is causing these engines to apparently "randomly" lunch cranks, and nobody has been able to definitively figure it out.

    I'm not pointing the finger at loose caps. I'm just sayin that a cap rattling around with a bearing shell on it ain't running the appropriate clearances for that bearing design. That would certainly lead to "less than optimal" oil pressure and/or the chance of the shell hitting the crank in an awkward position and that ball of twine could come unwound pretty quickly if that came to pass.

    While I'm wildly speculating, it could also result in extra deflection of the crank leading to fatigue.

    I don't know. All I know is the crank my car was born with went at < 120,000km and I'm hoping lightning doesn't strike twice.

  3. #63
    Join Date
    Nov 2018
    Location
    Hobart, Tasmania
    Posts
    561
    Total Downloaded
    0
    Quote Originally Posted by DiscoJeffster View Post
    But a bearing spins because it catches the rotating part. A bearing will not spin without a force pulling it. If you’ve ever installed a bearing into a shell, there is a decent force that keeps them in situ, exactly where you place them. They’re designed with a tension so they fit tight as. If a bearing turns and blocks a gallery, you can be sure the journal was not happy and the journal bound to the bearing to make it turn. The lead up to this was a problem - I find it far fetched a bearing moves itself then causes the blockage.
    The "force" you correctly mention is the crush between the two shells.
    It is the crush which basically relies on the shells not spinning and therefore blocking off the oil supply hole thus causing instant seizure.
    Is the crush not adequate in the first place at time of assembly, or does it lessen for some reason?

    the weird thing is that there doesn't seem to be any common denominators apart from a stuffed engine.
    mileage seems to be very variable; no serial number range; everyone seems to be over-servicing every 10k which is roughly twice as often as LR suggest; correct oil appears to be being used; reports of engines continuing to suffer even AFTER the release of Service Bulletins (which is extraordinary in itself when you think about it) and on it goes.
    Are the SDV6's doing it?
    More LR engines than Jaguar?
    The TDV8 doesn't seem to have the problem yet I assume the bearing assembly techniques/design etc would be similar.

    All we know is that JLR is keeping its cards very close to its chest as to why they fail apart from saying it is an assembly problem. That being the case, why are they continuing to experience problems AFTER the release of TWO S/Bulletins over a couple of years?

    Looking at photos of the shells, LR doesn't use the method of having "tab holes" in the caps and conrods which most definitely prevent the shells from turning even if the crush lessens. These have been used for decades in virtually any engine design. I guess they have saved a few cents of manufacturing costs to delete them.

  4. #64
    Join Date
    Mar 2016
    Location
    Perth
    Posts
    4,335
    Total Downloaded
    0
    Tabs on shells do not prevent them from turning. They were only to simplify assembly to ensure the bearing aligned with the lubrication hole. With automation they’re not as important. They were never to stop a bearing spinning. As I said, a bearing only spins with a friction and the tab won’t stop that. If a bearing grabs a journal it’s fubar
    2010 TDV6 3.0L Discovery 4 HSE
    2007 Audi RS4 (B7)

  5. #65
    Dfer Guest
    Quote Originally Posted by Eetab View Post
    Land Rover will not assume that every crank/bearing failure is as per the TSB and as such will not replace any engines out of warranty. To get Land Rover to replace an engine would be a very long and costly exercise.

    My MY15 3.0 Lt spun a bearing in March at 140,000 k's.

    The Land Rover quote of $38,000 is not an option, nor is a second hand engine at $15,000 and $5,000 labor from an independent. A rebuilt engine with a billet crank is on it's way from the UK.
    How did you go with the engine import? Feedback and costs appreciated.

  6. #66
    Join Date
    Apr 2008
    Location
    Brisbane,some of the time.
    Posts
    13,888
    Total Downloaded
    0
    Talking to my Indi last week,they have never seen a D4 2.7 destroy a crank,nor a Ford territory diesel.

    As we know these engines were modified and are not the same as the D3 2.7,so someone obviously knows what is going on with them.

  7. #67
    Join Date
    Jan 1970
    Location
    NSW SW Slopes
    Posts
    12,035
    Total Downloaded
    0
    What was the engine problem with the press release 2.7 Territory - a busted engine? I knew at the time but have since forgotten the details.
    MY21.5 L405 D350 Vogue SE with 19s. Produce LLAMS for LR/RR, Jeep GC/Dodge Ram
    VK2HFG and APRS W1 digi, RTK base station using LoRa

  8. #68
    Join Date
    Sep 2014
    Location
    Baldivis WA
    Posts
    2,293
    Total Downloaded
    0
    Apparently the location and material selection of the thrust washers on the crank is another issue. These are supposed to be sacrificial and maintain crank end float. Issue is the thrust washers are too hard, they wear the crank instead, end float increases and potentially game over. Also, thrust faces are normally located in the middle, between cylinders 3-4 on a v6 or 3-4 and 5-6 on a v8. On the 2.7 they are at the end of the crank for some reason. With an auro, there is normally no axial thrust on the crank, however with a manual there is. The failures dont seem to differentiate between auto or manual, but i don't have all the stats.

  9. #69
    Join Date
    Jan 2007
    Posts
    1,251
    Total Downloaded
    0
    Ford must have sussed something weak about the crank as they have replaced it with a forged unit plus beefing up other crank components for the F truck.

    Could be a truly great engine now...pity they road tested it on thousands of p'd off customers 😐

  10. #70
    Join Date
    Mar 2016
    Location
    Perth
    Posts
    4,335
    Total Downloaded
    0
    Quote Originally Posted by INter674 View Post
    Ford must have sussed something weak about the crank as they have replaced it with a forged unit plus beefing up other crank components for the F truck.

    Could be a truly great engine now...pity they road tested it on thousands of p'd off customers 2.7 and 3.0 Td V6 Crankshaft Bearing Failure known manufacturing fault
    It’s so much more complicated than simply forged is stronger than cast. It depends on what the carbon content is of the alloy used to cast the crank, what iron alloy is used in the forging process etc. It probably is, but it’s possibly more a marketing exercise than anything.
    2010 TDV6 3.0L Discovery 4 HSE
    2007 Audi RS4 (B7)

Page 7 of 11 FirstFirst ... 56789 ... LastLast

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Search AULRO.com ONLY!
Search All the Web!