D4 - Are they worth the risk?

gstuart said:

Found the report again of a guy getting a full engineering report on his failed D4 engine

Alas above my pay grade and know u guys have a lot more mechanical engineering knowledge than myself

https://www.disco3.co.uk/gallery/albums/userpics/23856/D4_russian_doc.pdf

Question 1: "Is there a fault in the car LAND ROVER DISCOVERY 4,".

Vehicle LAND ROVER DISCOVERY 4, to be in inoperable state due to engine failure. The
following defects are revealed:

- presence in oil of small metal inclusions formed by the process of mechanical friction;
- teaser and discolourations on and crankpins of the crankshaft, the crankshaft traces overheating
(buccal) in the region of the cylinder 2 and 5;
- welding by friction liner rod of the second cylinder.

- all indigenous damaged liners, the worn out portion of the internal and external, which is
adjacent to the block and closures of wear and scuffing does not except the liner third crank journal.
Insert a third crank journal (which is attached to the cylinder block) has a strong wear of the inner
surface and the part where the locking is completely split off. There is a deformation (flattening) radical
loose leaves in consequence of shock loads.

Question 2: "What is the cause of a fault in the car LAND ROVER DISCOVERY 4,

The short length of the crankshaft, and consequently narrow and crankpins result in high loads
on the liners. Narrow cheeks of the crankshaft through which pass yet drilling the oil supply lead to
high torsional loads on the crankshaft during operation and the stress concentration at the narrowest
section.

As a result of the engine, in consequence of the action on it of high torsional oscillations
perenagruzhaet radical loose, causing them to rotate. In the test engine was a displacement of the
insert with its indigenous partial destruction (split off the part where the liner disposed locking). The
displacement in turn led to the partial overlapping of oil supplying to the channel crankpin second
cylinder. overlap oil supplying channel result was a drop in oil pressure, and as a consequence of oil
starvation rod liner

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kermit_rr said:

My uneducated guess on the crank issue.. slight tolerance in the manufacturing of the crank.. in the right conditions, the piston gets hammered too hard and the rest of the crank can't keep up

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Stanleysteamer said:

I know a person who thinks that the crank problems are down to the lack of tabs on the bearing shells. Which I find hard to believe are not there in the first place.
It'd be a bit of work but one could take the engine apart and put them in oneself.

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Graculus said:

Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.

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lynall said:

I reckon that has been translated from chinesium!
I sort of, get what they are saying, but it is guess work.

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