4.6 SE - porous liners?

[thepsychoman]

Hi all,

Got a friend who has bought a non-runner 4.6 SE. Looks as though the car had a new engine at around 50,000 miles under LR warrantee and has just failed again (22,000 miles later)!

Heads removed and it looks as though the liners have gone porous.

So - two questions...

(a) Is it worth messing about with new liners, and if so, where to get em from?

(b) Is it a better bet to try to find and fit a 4.0 instead - as I understand that these dont suffer the liner problems?

Thanks all.

[thepsychoman]

No views....  :(

[thermidorthelobster]

Everybody was probably thinking somebody else would have a better comment.  Failing that, I'll bite.

Porous liners?  I've heard of porous blocks, and slipping liners, but not both.  The porous blocks apparently prevailed on earlier engines but wisdom has it don't occur so much on later ones.  Slipping liners are common in 4.6s but less so in 4.0s.

Most 4.6s last until about 95,000 miles so it sounds like your friend has been unlucky.

If it were me, I'd be very tempted to go to RPi Engineering and get one of their 4.6s instead.  I've not had one but from everything I've heard RPi really know what they're doing.  I think an RPi 4.6 would be a better bet than a Land Rover 4.0, plus you don't get the performance drop.  With the right engine and a decent warranty it should last forever.

I take it the current failed engine is out of warranty?

[hairyasswelder]

I think its RPI that do 'top hat' liners with the extra lip on the top to stop them slipping?
Dont know about the cost tho'

[Reggieroo]

A good friend of mine who works at Guy Salmon Land Rover as a mechanic, was telling me that nearly every P38 V8 that comes in has either had a new engine or needs a new one fitted & that goes for the 4.0 V8 too.

The reason being according to inside info is that Land Rover got another company to make the engines cheaper than they did for the Classics & Disco 1s in earlier years, therefore worse quality blocks etc  :shock:

Unless you get somebody else to rebuild it like the companies mentioned, it will just do it again.

There is another company who does this called ACR, they say that they have a proven permanent solution to the common cylinder block cracking problem.

Here is there website.  www.automotivecomp.com

[thepsychoman]

Thanks all.

Yeah - the vehicle is out of warrantee now...

The porous liner comment was based on my friend's observation of the engine once the heads were off - can't comment on whether or not he misunderstood the problem.

Either way it looks like just sourcing another RR engine of the same era looks like a bad idea, so we'll look into the other ideas mentioned.

Cheers

[Range Rover Blues]

4.6s have a worse reputation because the auto box tnds to hold higher gears longer than the 4.0, this causes a differential heating in the liner, higher heat near the top, which accelerates the problem.  This was mentioned in an article last year IIRC written with the help of RPI.

There are many contributery factors to the problem, not least of which os the thinning of the casting due to the bigger bore of the later engines and the tendancy to run lean, as often found on the 4.2 also.

[vxuk]

Mine suffered from slipped liners, i called a total of 3 places to see what the best price was, (this was about a year and half ago) I ended up getting the work done by a place called V8 Developments. They did a bang up job I must say. Not had a problem since. I decided that if i was going to do it, it was going to have something a little different.
Top hat liners
ported
stage 3 mods
fast road cam
and a few other little things

now puts out 280bhp and cost 4.5k, very pleased and done it very quick. I did have the option to send the block to them (they would sort out delivery) all I needed to do was remove the block and put it back in. I took the RR to them as I needed it quick as my main car in my wedding.

They should be able to provide you with the bits if you giving it a go.