Disco 2 with water in the oil

Hi
I am just about to sell two v8 mercs so I had to buy another v8, Plan is to swop my pajero diesel with a eco friendly v8 disco 2 , its LPG makes it sound a little better.

Anyway. the one I have found has water in the oil but no pressure in the water system or oil in the water. I believe that its most likely to be a crack in either seven or eight liner but as this point I'm yet to see the car, let alone look at whats wrong with it.

The questions are these.
1. Is it just the disco 4 L that has this issue or do the other engines also suffer.
2. How interchangeable are the engines, are either the older units or later or even the 4.6 range rover engine interchangeable physically or is everything in different place making it a nightmare job.
3. Do the dry liners need to be swopped after a total block strip or can they be changed once the heads and pistons are out of the way?
4. Is they anything else, silly or involved that could possible cause the water into the oil and not the other way around and without head gasket pressure into the water system?

I would very much like to have some constructive ideas on this issue so I can workout my 'method of madness' with the car.

Mark

If it was me, I'd be looking for a different one.

Col

Mark Pinsent said:

Hi
I am just about to sell two v8 mercs so I had to buy another v8, Plan is to swop my pajero diesel with a eco friendly v8 disco 2 , its LPG makes it sound a little better.

Anyway. the one I have found has water in the oil but no pressure in the water system or oil in the water. I believe that its most likely to be a crack in either seven or eight liner but as this point I'm yet to see the car, let alone look at whats wrong with it.

The questions are these.
1. Is it just the disco 4 L that has this issue or do the other engines also suffer.
2. How interchangeable are the engines, are either the older units or later or even the 4.6 range rover engine interchangeable physically or is everything in different place making it a nightmare job.
3. Do the dry liners need to be swopped after a total block strip or can they be changed once the heads and pistons are out of the way?
4. Is they anything else, silly or involved that could possible cause the water into the oil and not the other way around and without head gasket pressure into the water system?

I would very much like to have some constructive ideas on this issue so I can workout my 'method of madness' with the car.

Mark

Click to expand...

Unless it is really cheap and I mean really cheap ... walk away ...

The price I'm paying is fine, plenty of space to spend on repair or scrap and make a profit so no worries there.

I just feel that I'd probably quite like it once its all sorted and clearly if the crack their liners, then buying any of them could leave to the same problem in the future even if one hasn't got the issue yet.

I will either strip the block and get it sorted with new liners or swop the engine. If I do that, it would be either with a second hand unit or maybe a different V8 from another landy. that's the bit I need to know, about really. How different are they physically in terms of swopping and how robust are the liners in the other capacities?

All 94mm bore RV8's (ie all but the original 3.5) are prone to liner slippage, a condition that can be exasperated by running on LPG, this is due to the higher combustion chamber temperatures produced. As far as I'm aware the only cost effective solution is a replacement block.

I did some research and in talking to the local engineering firm, what you state there is exactly what he said. As this particular car had a brand new LPG kit costing £2300 in Feb, his thoughts were that the extra heat caused on the engine since then is the cause of the failure.
I will get the car this week and look around it carefully, if its otherwise good then I will sort out a liner repair and strip the block out accordingly. If the car is not so good, then I will strip it and sell the bits.

I believe that the liners are around 250 for the modified top hat version that butts up properly to the head gasket. I will investigate the engineering costs for the old liner removal, the extra machining to fit the top hat liners followed by the re bore of them to match the pistons. That plus the new piston rings and shells plus gaskets and loads of time will probably make it not worth it so I will go down the scrap route most likely.

All good fun.

Mark Pinsent said:

I did some research and in talking to the local engineering firm, what you state there is exactly what he said. As this particular car had a brand new LPG kit costing £2300 in Feb, his thoughts were that the extra heat caused on the engine since then is the cause of the failure.
I will get the car this week and look around it carefully, if its otherwise good then I will sort out a liner repair and strip the block out accordingly. If the car is not so good, then I will strip it and sell the bits.

I believe that the liners are around 250 for the modified top hat version that butts up properly to the head gasket. I will investigate the engineering costs for the old liner removal, the extra machining to fit the top hat liners followed by the re bore of them to match the pistons. That plus the new piston rings and shells plus gaskets and loads of time will probably make it not worth it so I will go down the scrap route most likely.

All good fun.

Click to expand...

If the vehicle is a really good buy and in nice condition I'd be inclined to spend the money on having the block "top hatted" it will give you a reliable engine set up for the long haul. The old 3.5 V8 was a good unit, but even they could slip liners, particularly if the liners were rebored too far oversize during an engine reco, in the later versions liner slip was more common from scratch, and it's just a pity they didn't put a bit more thought into block casting improvements for the bigger bores. I had a 3.5 in an old RRC that did just on 600k klms before it's first rebuild at that point got through requiring only a .020 oversize bore, no crank grind, only polish and new set of std mains and big end shells, new oil pump, it was still going strong long after the rebuild when I sold it on to the son of a friend. I would look at doing the fix up then enjoy the savings whilst enjoying the Disco.

Thanks for those points, it seems that even the original 3.5 is not going to be a solution here. Clearly landrover should have invested in the top hat liners many years ago. I guess they have been a bit lazy really, bearing in mind that the v8 was originally a small block american engine in the sixties.
I am considering something along those lines of fixing it so I eventually end up with a car worth keeping and replacing my 1994 pajero with. Its got to be a good one for that to happen as its amazing how good and reliable the pajero has been! I would go into long term reliability and stupid expensive things breaking conversations, to discuss the advantages of the jap stuff over the landrovers but that would make me look stupid as ultermately, for the third time, I am going back into landrovers and forgetting the reliable.

There is another cheap older disco 2 locally which would provide a source of parts and a usable engine while I repaired the later low mileage broken one. Clearly its never minor work to swop engines about but its always nice to use a car while you doing up a proper engine for it. Scraping another one instead would also give me a supply of useful bits plus a return on my investment for the bits that I don't actually use.

These things are often a labour of love. At least discos have some value. I find the price of v8 parts to be outrageous generally. Of course this may work in your favor but secondhand parts are quite cheap. Top hat lining is generally £1000 min. More at Turner's.

You could go for a 3.5 & stroke it, 'real steel' used to do a kit.

My plan is to probably scrap the car and use the brand new LPG kit on another one, which I will find at some point soon. I will get a solid chassis worth keeping as by my line of thought, mechanical stuff can always be sorted out but a rusty dog is always a rusty dog and if its a long term keeper, might as well find one worth having. I want a disco 2 again as I like my TD5 but I sold it on 6 years ago before it lost all its value. Now that they are cheap, its time again. I want a manual ideally but would have an Auto again as they are much more common as long as it hasn't got water issues. I will then keep a close eye on what happens next with that one. Meanwhile I will strip the one I have, sell the bits I don't need to get some money back and then get its engine properly sorted. So eventually, I will have a manual (or Auto) es v8 with a good LPG kit and a reconditioned engine.

This plan might take a year or two to complete but its good to have a focus!

How interchangeable is the 3.5 and the 3.9 with the manifolds and other parts from the 4L unit in the disco. Clearly they are all externally based on the same block but how many external casting bits were changed etc.
I am only wondering about converting the engine retro as the power is less vital to me than the long term reliability. Swopping complete engines around without having to do more than manifolds and other external bits is all relatively simple and cheap.
Mind you, that's all assuming I will be able to pick up a good older unit.

Mark Pinsent said:

How interchangeable is the 3.5 and the 3.9 with the manifolds and other parts from the 4L unit in the disco. Clearly they are all externally based on the same block but how many external casting bits were changed etc.
I am only wondering about converting the engine retro as the power is less vital to me than the long term reliability. Swopping complete engines around without having to do more than manifolds and other external bits is all relatively simple and cheap.
Mind you, that's all assuming I will be able to pick up a good older unit.

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3.5 and 3.9/4.2 are identical apart from bore diameter, the next generation 4 and 4.6 have a machining for crank sensor and knock sensors, and larger crank,3.5 with 3.9 efi kit makes a robust engine

Thats very helpful. I have spotted a 3.9 that might prove cheap enough to grab. From what you say, I could swop over without too much effort and then I could in time sort the disco engine out making a good recon while still using the car on the other engine. All worth considering. Mind you, I just bid on another car so if I win that disco, I will be swopping lpg kits and then scrapping the one I have instead. At least I won't get bored.

I now have another engine ready to go into the disco which cost me 230. I believe its ok but I will know more soon. Maybe I will have a cheap lpg disco after all. I know that I have to swop it all over but thats normally quite fun if it goes well.