Thread: Can I swap a 3.9 with a 4.2 in a 1994 discovery

4.2 will fit butnot many around.

ECU may need some rework.
Slap a 4.6 in or reco your motor if possible to 5 lt. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img] [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

Michael.

Astro, All Range Rover motors up to the 4.6 in the 2001 Range Rover are "backward compatable". the latrer ones need a few simple mods to fit the good parts of your engine, which is usually the heads, front cover, manifolds etc. So you can fit a 3.5, 3.9, 4.0, 4.6. There was no 4.2 in Australia.
When you say the engine"blew". What does that mean? Are there holes in the block, or did it blow a head gasket. What specifically happened? It helps for us to know before we give advice.
Regards Philip A

4.2 was in the LSE

Michael.

AFAIK, LSE to Australia had 3.9, as Rover were unwilling to emission certify the 4.2 for a small volume of cars.
Regards Philip A

Originally posted by Astro
I have a 1994 discovery with a 3.9 V8. It only had 130,000 on the clock and the motor blew the other day. No reason, has been serviced every 3 months and my mechanic is scratching his head. Anyway, am looking for a new engine and one mechanic reckons you can only fit a 3.9 in the 1994 discovery and another reckons you can fit anything up to the 4.4. Who is right? I only joined the website tonight, so I hope I am asking the right question the right way.
Thanks in advance for any info you can give me.

astro please be more specific when you say it Blew.
As Phillip said , it could be a head gasket .
Then all is not lost, it is repairable.

Originally Posted by PhilipA

Astro, All Range Rover motors up to the 4.6 in the 2001 Range Rover are "backward compatable". the latrer ones need a few simple mods to fit the good parts of your engine, which is usually the heads, front cover, manifolds etc. So you can fit a 3.5, 3.9, 4.0, 4.6. There was no 4.2 in Australia.
When you say the engine"blew". What does that mean? Are there holes in the block, or did it blow a head gasket. What specifically happened? It helps for us to know before we give advice.
Regards Philip A

PhilipA. Thanks for anwering. I hope I am replying the correct way, first time user. When I said the engine blew, while my wife was driving the car she heard a loud noise and smoke started coming from under the bonnet. When the mechanic checked, he found a hole blown through the side of the block. He has not opened up the motor as he said from the damage he can see, he reckons there would be major damage inside, probably more than it would be worth trying to repair.[/quote]

8) ahh, women drivers!
she's probably feeling a little bit sad that everyone thinks she broke it.
they break.
not her fault, give her a cuddle, and tell her that it is only going to cost squillions.

first i've heard of one having a catastrophic failure.
sounds like it threw a leg out.
ie to the young'uns,
let a con rod go, which broke out of the block.
i think it looks like the mechanic is right, if the block is holed then, basically your are up for a new engine.
i don't think you will save anything by messing oround for bits, unless you are mechanically into engine rebuilds.
of course the engine needs to be removed , stripped and then they can work out a repair cost.
you didn't say how many k'm on the truck, and i might have missed how old it is, so getting a replacement maywell be easier than repairing

What part of the world are you in Astro??

(click on PROFILE, scroll down to location, Bingo!)