Please do post. I've seen several blocks crack behind the liner and cause liner shift or distortion but never a slipped liner on a Thor engine. The cracks almost always eminate from a head bolt which was way overtorqued. Please don't think I'm being sarcastic, I'd genuinely like to see it for my own information.

 

The indent in the head + hg thickness was 1/8 and the liner sat 1/8 below the deck, so in total about 1/4 movement. The lip at the bottom of the cylinder was peeled away from the pounding, it's only a matter of time until the liner works its way down, or through the head.
We pulled the liner and pressure tested the block up to 50psi and found no leaks or cracks in the cylinder wall. The next step was to heat the block and pressure test, but I found a short block and further tests were pointless.

 

On one of the other Land Rover forums a respected member posted this, I think it sums up the whole debate:
Originally Posted by p76rangie
Basically one part of the pump is on the crank and the other half is in the timing cover. Therefore if the timing cover is not correctly aligned with the crank the oil pump can fail. This alignment occurs using dowels that line up the timing cover and the motor. At one stage (during the vin range listed) there was a slack operator on the machine drilling the dowel holes and some were not drilled in the correct place. As it was only one machine and operator and also not all blocks done by that operator, it was difficult to identify what blocks were affected. So they just put out a bulletin listing all the blocks produced by all operators over the whole period. Only a small percentage of blocks actually covered in that VIN range are actually affected

 

I am toying with the idea of dropping a P38A 4.6 into my son's 2001 Disco. I have read the engine managements are the same. I have read that a straight motor swap is all you need to do and I have also read that you have to switch out the ECU also. Logic tells me the engine management system would compensate for the added displacement by monitoring the performance and exhaust gases and adjusting the intake accordingly. Considering that my logic has gotten me in more trouble than not I am going to keep researching until I find a convincing argument. I would loved to hear from those who have completed a 4.0 to 4.6 conversion or vice-versa and what they did and learned from it. Thanks.

 

All the 03 disco motors have already blown up and been replaced, (I blew one up with 7k on it driving to burger king for lunch, a service writer blew a loaner up on the way back to the dealer with a customer in the car) and if you find a 03 motor with a blown up front timing cover/oil pump you can swap a used/slightly worn timing cover onto it and the slight dowel offset wont effect the used pumps operation. I know this because I installed a 4.6 motor with a blown oil pump in my 01 discovery. Cleaned out the shrapnel, swapped the timing cover, put 30k miles on it, sold it. I have also seen high mileage oil pumps explode due to small clogged oil filters and malfunctioning (stuck closed) bypass valves.

And yes the 4.0/4/6 motors are a direct swap and require no changes to anything.

 

Its possible. The sleeve does not sit on a ledge in the bottom of the block, they bored the sleeve size all the way through the bottom on all the motors I've seen. You cant really overtorque the headbolts, they only get so tight, then start to stretch until they snap. What you CAN do, is fail to blow out the headbolt holes with air and hydrolock a headbolt into the block until it cracks the block or rips the threads out. I have seen that happen to a seasoned vet.

 

On my 2003 block there is a ridge at the bottom of the cylinder bore, the sleeve cannot go further down than this ridge. The sleeve and the ridge are bored flush so it may appear like one continuous sleeve. This may have changed in 2003 or earlier, I don't know what the earlier blocks look like. At least this is what I saw in my block, for all I know the engine may have been replaced at some time after 2003... who knows. Just saying what my block looks like...

 

Hey guys I've got a 2003 with a 134,000 miles. I've had it since 108,000 miles. I've long read about the vin range failures and my truck does indeed fall in this range. However with this much mileage I'm wondering at this point if I am safe?

I've gone through the carfax fax and available information from the passport to service and there is no information regarding oil pump replacement or engine replacement. The previous owner always took the car to the dealer for service and has been pretty well maintained on schedule since it's beginning(as per passport to service booklet).

Of course there is the possibility that there was work done privately but I'm not sure of the odds of that. The guy I bought from was a rich kid who from what I could tell always had the dealer do work for him.

I'm just wandering if it would be a good idea to replace the oil pump for good measure or not. Also, my friend who is a well experienced mechanic thinks that the lower half of the motor has been taken apart/replaced/serviced before. But from what I have read on this forum is that the oil pump issue cannot be solved with a rebuilt motor, only total replacement of the motor or continuous replacement of the oil pump.

I guess another thing I would like to know is, what are the odds that someone has replaced the oil pump(like some temporary solutions suggested on this forum), and that motor is indeed faulty?

sorry for the lengthy post

 

At that mileage it would have failed already if it wanted to, I think the issue is moot.
Install an oil pressure gauge and monitor the pressure. Ideally you want to stay above 10psi at hot idle. If you do not see anything in the service record then most likely it was not done. Chances are good that the PO would not have had it done privately. You can always look around the engine for signs of private work, like broken plastic parts and replaced hose clamps etc, private guys like fooking these things up.

 

Alright thanks for your response. There are some hose clamps that are replaced but I believe that was done by a local private mechanic that works on land rovers. I've had some work done there before. My friends and I recently did a head gasket job on it, I noticed that some of the hoses were glued. LR must not have faith in their clamps.

And ditto on the pressure gauge I'll definitely be installing that.