Motor Swap

[Tinto]

I have a 94 NAS D90 with a 3.9l distributor timed V8 that has 165,000 miles on the clock. I would like to replace the motor with a 4.0l motor that has a distributorless engine management system. I'm not sure, but I think it is a GEMS system. I purchased the 4.0 from a very well known genuine parts company and was told that it would "bolt right in and run" Can I run this motor with my current ECU and electronic stuff? Another enthusist told me I could change the cam on the 4.0, put a distributor in, and run it. options? advice? pro's and con's?

[TerryS]

The short answer is yes. The full version is yes, But..............
The Lucas 14CUX system requires inputs from O2 sensors, Air flow meter, fuel temp sensor, water temp sensor and throttle position sensor. None of that on a Gems engine is compatible. You deffinately want to keep the Lucas managenment system, rather than getting into crank position snesor timing. It will require that you swap the intake manifold (complete with plenum,(with idle air servo motor and control valve) ram plate, fuel rail and injectors.(they will be the same on both engines so use the lower milage ones)
You will need to get a front cover gasket for a 3.9, and use you old front cover on the 4.0, in order to have provision for the distributor. You will also need to change cams in order to drive the distributor. You need to make up a spacer for the main pulley because of the difference in the cranks.
When you're all done, you will have spent as much time and money as had you rebuilt your 3.9, which may be a more practical option, provided the bottom end isn't bad. (i.e. bad bores, liners, spun main or rod journals.)
So yes, a 4.0 will bolt right in, but it won't run without alot of mods. If the 4.0 was from an automatic, you'll need to use your old flywheel, and be prepared to have difficulty with the flywheel bolts (Allen head caps, buy new ones)

[WCURoverD90]

Get a 4.6 for it.....

[TerryS]

Originally Posted by WCURoverD90

Get a 4.6 for it.....

I can't disagree, a 4.6 Bosch engine is a nice piece of kit.(but not the 4.6 from a preBosch P38) The best change was the cross-bolted bottom end, but the induction system is pretty nice too. I don't know of anyone who has ever converted a 4.6 Bosch to 14CUX hotwire injection management, but still used the Bosch intake. It might be a tricky proposition to install a full blown bosch system in a D90, since there is crosstalk to the BECM and security systems. I suppose it's possible to fool one into thinking it's still in a D2 or late P38. It's the kind of challenge I enjoy, but they don't give them away and anytime I have seen used 4.6 engine for sale, they never came with the multitudee of electronics from the car. Gas prices heading back up again has brought the plan of 300Tdi or 2.8TGV back to the front burner.

[Geobloke]

I disagree compeltely, import a 2.8L International TDI from south of the border and stick that in!! BRing on the Diesel!!!!

Or import a LR TDI from the UK, they are on EBay all the time!!!

[TerryS]

Originally Posted by Geobloke

I disagree compeltely, import a 2.8L International TDI from south of the border and stick that in!! BRing on the Diesel!!!!

Or import a LR TDI from the UK, they are on EBay all the time!!!

Only if life were that simple.

What you see "...on EBay all the time!!!" is ebay UK. Im sure you have never had a reason to check, but what is listed on ebay UK is not necessarily listed on ebay in the US. Not only that, unless one is a vloume imported, the discounts available on LTL (less than loaded) frieghts are unavailable. The freight is horrendous (just sent a few pints of my 2006 maple syrup to the UK, at $14 postage. I used to bring in specialty stainless steel castings (2-3 hundred thousand pounds per year)from the UK (airfreight at that) and know what Im saying.
There is no one in the US importing the 2.8TGV on a commercial basis, for automotive applications, though it is coming into Miami as a marine engine.
It was originally offered by many Canadians for around $4500 US, but when they figured out that it could not be commercially imported for auto use into the US, the price suddenly doubled (I say we declare war on them Canadians) Check out the current price by Britanica Restorations. Just last saturday night, AAXD, PaulGrant & I got together for a few pints and I said I wanted to find three others who also wanted one, so that we could get the price break for shipping. Any takers?
While I agree with you, that they are both good diesels, if you could get gasoline for $2.36 a gallon (1pound37p) you'd be lovin my 4.2

[Geobloke]

Yeah I was having this very conversation with another US NAS D90 owner, he said basically the same thing. How about putting a GMC V8 diesel in to it? People over here do it and it works a treat. Another way is to get a 200 or 300TDI over here in the UK (via Ebay or other) and then ship it out to the US, would probably be a heck of alot cheaper to do than buying a LR engine over there! Can't believe the mark up on LR products in the US, your really being taken for a ride! Guess that come from the one or two companies having near enough a monopoly!!

[TerryS]

Originally Posted by Geobloke

How about putting a GMC V8 diesel in to it? People over here do it and it works a treat. Another way is to get a 200 or 300TDI over here in the UK (via Ebay or other) and then ship it out to the US, would probably be a heck of alot cheaper to do than buying a LR engine over there!

I am of the opinion, and it may not be one universally shared, that the GM, or Ford diesels are too heavy for the suspension geometry of a Defender. That, and they are huge compared to the 4.2, or other landie V8s.

I know there are quite a few who have bought 300Tdi engines from breakers like Equicar. I was chatting with one fellow last fall who bought a 300Tdi, R380 and LT230 and had it delivered for $4500, which isn't too bad, but not great when you consider that the freight was over $2Grand of that $4500.
Like any ebay purchase, the variety in honesty and accuracy is vast, and dropping that much with a private seller, that far away is risky at best.
I have bought many vehicles off ebay, but in each case except one, made the trip to check it out first hand. Good case in point; My son drove 5 hrs round trip to check out a 110 this past weekend which, if you took the sellers word at face value, was a good truck. It turned out that there was nothing salvagable to the frame, forget outriggers, how about completely rotted frame channels, bulkhead that saw salt water regularly, and holier than JC himself, and an engine which sounded like marbles in a coffee tin.
I may well go with one of the breakers in LROI or LRE, but I think I'll pass on a 3000 private seller.

[LRover]

Personally I like the 6.2 GM diesel conversion idea. For sure the Ford engines are way to heavy but the 6.2 base weight is only 70lbs heaver than the 300tdi. I've seen a Disco Series 1 here in the US with the conversion and we wheeled together all day and it did very well. The stock ZF handled the increased power through a torque converter supplied by Samuri Conversions in the UK. The exhaust manifolds, motor mounts and adapter plate were also supplied by them from what I was told. The bad news is that with any conversion there are a host of small problems and when you deal with a different make engine often you have to solve them yourself. The nice thing about the 300tdi engine is that all the parts are off the shelf.

[onslow]

My 87 6.2l auto rangie sadly removing the GM due to rip off diesel prices getting a 4.6 and running it on LPG coz its less than half the price of diesel here, totally awesome conversion no comparison to the 300TDi would eat one for breakfast torque is incredible, smooth power I get 22-28 mpg depending on how gentle I am,damn good conversion in my opinion and ive had a few conversions in my time.

[TerryS]

Damn, Onslow. If it was the year 2012, I'd make you an offer for your Rangie. That is perhaps the nicest one I have seen on this board. This 25 year rule on importing is BS to the third power.

[Bene]

im prbably a bit late for this, but a 4.0 is only a crankshaft and cam away from a 4.6.