D2 V8, engine swap.

Hi Folks,

Got the well known overheating issue with my 03/52 D2 V8 Thor. All usual 'easy' tests done (blocked rad?, viscous coupling etc), so over to the hard bits;
Heads off, pressure tested, no problems.
Inlet manifold, pressure tested, no problems.
Although I found no loss of water until the day she overheated on me we have noted evidence of a 'steam cleaning' effect on piston 5.
I'm getting differing ideas from the guy who tested the components (skim the heads, replace gaskets, all good) and mechanic doing the job (can't see how water can get into piston 5 so must be a block issue). Only fair to mention the guy doing the job is a well known Landrover mechanic. Pressure testing guy more of an all round engineer.
So, as you can imagine, I have a bit of a conundrum. Do I risk putting the whole thing back together only to be back at square one? Or, do I replace the engine, given 80% of the removal work is already done.
Leaves me with two questions;
1, Has anyone any suggestions as to what is actually the problem here? And perhaps agree/ disagree with one of the guys I am dealing with?
2, If I replace the engine, I cannot find any decent 4.0's, but found a couple of 4.6's in good low mileage condition. So, if I go 4.6, can I use the 4.0 ecu, injectors, and the D2 auto gearbox? Is there any other pitfalls to this idea that I haven't seen? As far as I know the engines are almost identical with only internal parts being different, correct me if I am wrong.

Any ideas/thoughts gratefully received.

Ratman.

What did the head gaskets look like.
was the fire ring (think that’s what they call it, the metal ring around the cylinders) was it battered ?
has the block had a good inspection for liner movement.

The ecu (in the p38) has both maps and can be changed from 4.0-4.6. So possibly the same for the disco.

Dont think it would be a good idea running the 4.6 through an hp22 which also has the smaller torque converter

J

There are 3 TCs in use on the D2, smallest for TD5 and that is under specced, the 4.0 and the 4.6

4.6 also has a different box, not sure if 4.0 is same as TD5 or 4.6 I THINK TD5 and again that is underspecced.

I would get advice from Ashcroft transmissions OR get a 4.6 box and TC

How much was your running Thor engine overheating in degrees? I hope you didn't go into the red on by the instrument cluster's temp gauge!
Sorry if I missed it but did you check/replace the thermostat? Swap out the cream colored 88°C thermostat for a grey soft-spring 82°C part # PEL500110 which is for a Td5.
What type of coolant are you using in your V8? I much prefer the rare Valvoline G-05 HOAT coolant over the orange Dexcool OAT coolant for my V8.

Could it be the block is porous which might explain the weird "cleanliness" in that cylinder?

MJI said:

OR get a 4.6 box and TC

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But then the LT230 wont go straight on without fettling.
The 24 is electronic unless fettled too.
Neither of which is not doable.

Or get a 22 with 24 bits in from ashcroft.

Or change the crank, rods & pistons over and make the 4.6 a 4.0

Or hold out a bit longer to find a 4.0.

J

RATMAND2V8 said:

can't see how water can get into piston 5 so must be a block issue

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marjon said:

has the block had a good inspection for liner movement.

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+ see post #5

Any answers to the above? You could maybe do some sort of a top hat repair maybe? If this is the case.
Don't know how often this problem occurs but do know that you can buy engines with this already done, from Turners or some such.

Stanleysteamer said:

+ see post #5

Any answers to the above? You could maybe do some sort of a top hat repair maybe? If this is the case.
Don't know how often this problem occurs but do know that you can buy engines with this already done, from Turners or some such.

Click to expand...

The V8 has liners which are prone to move as when this happens its US. Its not what I would call a porous block.

We have been through the head gasket, head skimming to find we had slipped liner. so ended up shipping a "top hatted" engine to here. We had 120k on ours before it happened

The condition can be checked but is not always easy too see, to the untrained eye or somebody that is convinced its just the head gasket. Which is why most suspect head gaskets and skim heads.
The liner moves which is why some say you can hear the "tapping" (never noticed it on ours) it will batter the "fire ring" thus moving more and allow combustion gas into water jacket, and steam back in when it overheats.
Aluminum block and steel liners, with old block machining equipment seems to be to blame.
Oh and top ats are not cheap

J

marjon said:

The V8 has liners which are prone to move as when this happens its US. Its not what I would call a porous block.

We have been through the head gasket, head skimming to find we had slipped liner. so ended up shipping a "top hatted" engine to here. We had 120k on ours before it happened

The condition can be checked but is not always easy too see, to the untrained eye or somebody that is convinced its just the head gasket. Which is why most suspect head gaskets and skim heads.
The liner moves which is why some say you can hear the "tapping" (never noticed it on ours) it will batter the "fire ring" thus moving more and allow combustion gas into water jacket, and steam back in when it overheats.
Aluminum block and steel liners, with old block machining equipment seems to be to blame.
Oh and top ats are not cheap

J

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So I was kind of right then? For once!

Stanleysteamer said:

So I was kind of right then? For once!

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Yeah if you want

J

marjon said:

Yeah if you want

J

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Well thank you kind Sir.
Nice to get a compliment!

I have just had an enormous put down from some wimmins on Nextdoor for having said "Well done" to her. Apparently this is "patronising" and a load of other old gunk including "from a man".

I just meant to pay her a compliment and as I said back to her, I'd have said it to a man, a wimmins or an LGBGT+
WTFFFFFF!