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I realise that this company is in the Uk but it may be worth getting a quote and delivery time as a comparison Low Mileage Landrover Discovery-3 Engines At Cheap Prices
These guys also might be worth talking to http://www.triumphroverspares.com.au...5&parent2id=17
Any idea of waht caused caused the TDV6 melt downs Rob? And any idea of out of how many vehicles did the 7 or so failures appled?Quote:
Originally Posted by RFollia
Cheers
Did the valve drop into the cylinder , or didn't it ?Quote:
Originally Posted by FOMOCO
Has the 5th piston contacted the valve because the belt
timing has gone ?
....... and ........ nobody gets off their ass for just a case of beer ;
$5000 maybe ..........;)
[QUOTE=Neil P;1449140]Did the valve drop into the cylinder , or didn't it ?
Has the 5th piston contacted the valve because the belt
timing has gone ?
....... /QUOTE]
I am a bit confused as well - head gasket going does not cause a valve to drop. Likewise any new oil of almost any spec (within reason of cause) will not cause an engine to fail in the short term and will not cause head gasket failure nor the dropping of a valve - as you mentioned though a valve timing issue could cause a valve to hit a piston with all sorts of issues - but not blow a head gasket. Likewise a fatigue fracture could cause a dropped valve but would normally only show up at high milage.
There is conflicting info here so until investigated cannot be resolved - last service by ultratune will not be an issue - there is nothing they can do to cause this sort of damage. Most likely a valve timing issue with a manufacturing fault.
If the head gasket did let go then how does it cause a valve to hit the piston - if the cylinder is full of coolant would a valve be damaged as it tries to open or would it just relieve the pressure in the cylinder and the coolant comes out.
Seems to me there are some unrelated things going on here. Why do the engines fail in the Explorer? giving it the nickname "Exploder" - is what happened simply the same?
Garry
[quote=garrycol;1449169]Not necessarily unrelated - one possibility is the head coming off a valve, damages piston, head and block, so coolant gets into the oil from the cracked block or head. Valve failure of this sort, unless in a seriously modified engine or badly out of tune, i.e. retarded spark or very lean mixture, (is that possible on that engine?), just about has to be a manufacturing fault at that mileage. But whether you can prove it is another matter. Be very interesting to see the damage.Quote:
Originally Posted by Neil P
John
Whilst all this has been discussed , what about the timing chain
tensioners and cassette ; Is the 2005 onwards 4.0l v6 the same
nonmetallic parts as the 1997-2005 US engine ? Most US failures
were on plus 80000 mile units from early 2000's production.
Haven't seen any LR3 4.0 reports on US LandRover sites , have
any of you ?
Here’s an update from the weekend, I’ll upload what photos I have tonight. After arguing with RAC that I was due a 2nd free town then waiting over 3 hours for it I've taken the car across to the Dealer for a proper diagnosis to find the route cause, RAC’s story didn’t add up and their investigation wasn’t very comprehensive.
The piston on the nearside rear cylinder (LHD) has a valve shaped hole on the low side and the liner has a hairline crack, presumably the head of the valve is in the sump and yet to be retrieved.
The water galleries are very clean and almost white in colour, not sure if this is normal, but I suspect it could have been running hot; the timing chain’s front and back are both intact. The head is peppered with indents from the valve that’s been rattling around in the combustion chamber, until it made its way through the piston. Water has found its way into the oil and mixed, dark brown mayonnaise; the tops of the pistons on the nearside bank show signs of water damage and the head gasket is discoloured black around the joint between the cylinders. From what I can understand the head gasket has been passing but there was no sign of rise on the temp gauge or any oil or engine warning lights on the dash; it just gave way all of a sudden.
RAC missed it, but I spotted the valve stem and a few bits of what look like they could be rocker in the exhaust (there’s a small perforated plate in the downpipe that has captured it). When it let go we heard a “tinkle” sound from the bulkhead area, obviously the valve giving way and shooting off down the header, maybe a valve manufacturing defect then? I’m not sure if it was the inlet or exhaust valve, I think it was the smaller of the two.
So did the head gasket fail first, or was it a timing issue that damaged the valve? How can I tell if it was a timing issue, could a sensor have failed has the ECU failed?
Would the volume of water leaked from a head gasket failure cause a “hydraulic-ed” engine (i.e. when the bores fill with water from cracked block, head gasket or drowning the car) if the valve is open on the compression stroke would the incompressible water excerpt a force on the valve causing the stem to bend and eventually break, i.e. would it jam in the valve guide?
Castrol are coming to take a sample of oil for analysis (foc), service record shows they used 5W30, Valvoline Synpower MST from the description
But what happened is still inconclusive; the Land Rover Dealer has said he couldn’t believe what he saw when he opened the bonnet – he will say the same when I open my wallet! I’d offer $5k for an answer if I had it :o) I’ve waited years to own a Landy and am gutted this has happened: I’m contemplating buying a box of matches and a Hyundai Getz!!!
I'll take a complete guess and say a new motor ( in ripoff Oz )
will be waaaaaay more expensive than a rebuild . You'll have to
repair it because it's scrap if not working . Then sell it .
PS The coolant pressure is only 20lb or so vs. three figures
in the piston at detonation . Coolant entering the cylinder
would be very little and slow too. You'd get cold engine misfiring
and stalling if it was head gasket initiated , and more like
CO2 entering the coolant rather than liquid in the cylinder.
I've had 3 engines do this in my time , and all alloy head
jobs that heat fail . Never happened to me on an all steel engine ,
but it can ofcourse
Here are some photos of the block and head...
Attachment 34404
Attachment 34405
Attachment 34406
It's possibly hydraulic-ed and the valve has bent when trying to open against the pressure in the cylinder. Dark brown mayo oil is a little water in oil, white water is oil in water. Possibly head gasket went between oil and water galleries which mixed fluids (less water in oil as pressure higher, but leaks back as cools). Oil contamination lead to other failures but head gasket further failed into cylinder where it filled and .....epic fail.
