Quick Reference: Swap your 4.0 block with a 4.2
OK, now that the car is in the garage and the 4.2 in on a stand I think I'm starting to see the pieces of the puzzle. I spent a good hour looking at this today strategy-zing on how to tackle this. I'm totally new to Jags so please bear with me
Avos and Count,
I see in the guide that it spells out to swap the lower sump from the 4.0 to the 4.2, my question is why? I see that the outputs for the oil cooler bypass are different, and that there is some additional sensors ( oil pressure?) in the sump on the 4.2 . Also, I'm not sure but the flexplate sensor looks like it might be offset differently?
Reason why I'm asking is, that I'm sure that the improved oiling system was designed to work as a system (I'm sure you guys know better than I), I just want to make sure that it's not a step back by using the lower sump. Looking at the 4.2 I actually like the location of the oil filter better and the fact that the bypass valve is accessible from the outside. So other than plumbing the oil cooler and plugging the sensors, is there any other reason to reuse the 4.0 lower sump and pan?

Avos and Count,
I see in the guide that it spells out to swap the lower sump from the 4.0 to the 4.2, my question is why? I see that the outputs for the oil cooler bypass are different, and that there is some additional sensors ( oil pressure?) in the sump on the 4.2 . Also, I'm not sure but the flexplate sensor looks like it might be offset differently?
Reason why I'm asking is, that I'm sure that the improved oiling system was designed to work as a system (I'm sure you guys know better than I), I just want to make sure that it's not a step back by using the lower sump. Looking at the 4.2 I actually like the location of the oil filter better and the fact that the bypass valve is accessible from the outside. So other than plumbing the oil cooler and plugging the sensors, is there any other reason to reuse the 4.0 lower sump and pan?
As long as the more modern sump physically fits in the X308 I dont see a problem using it. It may incorporate some advancements in the windage tray design and the sensors are probably more for the AJ33 torque based EMS rather than the 16 bit system on the AJ26/27. The other differences will be mainly for packaging.
@adam699,
The oil filter with the newer sump plate is placed in such a position that you can't easily install a larger lower pulley (if that would be on the list of course).
Imho it is a lot of effort of which I can't see the benifits.
Have now also added more 4.2 injector info, you might be interested
The oil filter with the newer sump plate is placed in such a position that you can't easily install a larger lower pulley (if that would be on the list of course).
Imho it is a lot of effort of which I can't see the benifits.
Have now also added more 4.2 injector info, you might be interested
Last edited by avos; Sep 12, 2011 at 02:30 AM.
Guys, I have another dilemma. Why would I want to swap the front cover from the 4.0 to the 4.2? Also, I noticed that the accessory drive and front pulley are a bit different. Aside from the fact that the 4.2 has a 7 rib setup vs 8 rib on the 4.0 It actually looks like the 4.2 has a bigger balancer/pulley and a smaller supercharger pulley. I didn't see any crank sensors nor any sensors in the front cover. I'd rather not touch it unless I really have to.
Opening for the main pulley on the front cover is different between the 4.2 and 4.0 cars, and the lower pulley is indeed larger in diameter. If you leave all, you need to check if the airco could work with your car (electronically and pipe fitting wise), and you need to swap the alternator as the electronics are different (and use the 7 rib pulley on your old alternator). I would guess you could leave the steering pump. If the airco would be questionable, you could check if you could swap the pulley mechanism , as personally would think it risky to use a 7 rib belt on 8 rib pulleys, even though it will align, you will be missing a side lip on one side, so in theory the belt could hop.
Opening for the main pulley on the front cover is different between the 4.2 and 4.0 cars, and the lower pulley is indeed larger in diameter. If you leave all, you need to check if the airco could work with your car (electronically and pipe fitting wise), and you need to swap the alternator as the electronics are different (and use the 7 rib pulley on your old alternator). I would guess you could leave the steering pump. If the airco would be questionable, you could check if you could swap the pulley mechanism , as personally would think it risky to use a 7 rib belt on 8 rib pulleys, even though it will align, you will be missing a side lip on one side, so in theory the belt could hop.
I also think that using the 7 rib belt would create less drag, which is probably why it was redesigned. The tensioners appear to be a bit different too especially on the drivers side by the AC/PS bracket. I don't have any accessories from the 4.2 so I got to reuse the Alternator, AC compressor, and the PS. I haven't really had a chance to tear into the bottom part of the motor.Today, I took apart most of the top off the 4.2 and started on the 4.0.
One of the things I noticed was that the supercharger of the 4.2 had black rotors while the 4.0 one has silver colored ones?? Also looks like the one off the 4.0 had something etched on it and it looked like the lips of the triangle opening by the rotors were a bit grinded off.
I also found out why the 4.0 lost it's oil. The valve covers were leaking baldly, the plugs were drowned in oil when I pulled the coilpacks.
I don't think the belt will hop if you use the 8 rib pulley. Tension will keep it running straight. If the pitch of the belt ( distance between gooves ) is the same it should stay where you place it. Might even take care of slight missalignment issues.
Does anyone know anybody who does this swap in California? I need a new engine for my 2000 xkr, and I want to go with the 4.2. I don't have the time or expertise to do it myself.
Have updated the info in the 1st post for the Range Rover 4.2 SC block. Have just done a conversion yesterday, and know now myself what has to be done. It is not a common block, but thought to mention it anyhow as there could be some similarities with the Lincoln LS block for the NA engines.
Gentlemen! I have a 98 XJR, as seen in my thread here- https://www.jaguarforums.com/forum/x...-repair-97146/
I am making up the shopping list, and it is getting depressing! So here's the question- there's a local guy parting out a 2005 XJR. From my reading, going XJR 4.2 into an XJR 4.0 body doesn't sound too bad. What am I looking at? Please take the time to help, I am serious on this possible swap. I just get confused on what I can or cannot reuse in my particular case.
Thanks in advance!
I am making up the shopping list, and it is getting depressing! So here's the question- there's a local guy parting out a 2005 XJR. From my reading, going XJR 4.2 into an XJR 4.0 body doesn't sound too bad. What am I looking at? Please take the time to help, I am serious on this possible swap. I just get confused on what I can or cannot reuse in my particular case.
Thanks in advance!
Its all in the thread. Ideally also go for the 4.2 injectors, but that requires that you use 4.2 XKR (2003-2009) intake manifolds and intercoolers, and a new FPR as you need to up the fuel pressure form 43 to 65 psi (which these new injectors require). If you re-use your intake manifolds/intercoolers you need to make a plate like adam699 has done as the V8 plate does not align up with the 4.0 intercoolers, or buy a TS kit, as then you get a custom adjustment with it ;-).
Have a look at the intercoolers, its a totally different design and will not fit. You can actually use the intake manifolds form the 4.2 XJR, but you must use the 4.2 XKR intercoolers with them.
Alright, I see now the issue would,be the physical clearance from the hood. Would an XKR 4.2 be a relatively straightforward swap, then? Or an XJR with XKR intercoolers?
I ask because it seems deceptively simple when I read the first few posts.
Thanks again Rob
I ask because it seems deceptively simple when I read the first few posts.
Thanks again Rob
Depends whats harder to find, ie 2e hand 4.2 XKR intercoolers (and the engine you already can get now) or a complete 4.2 XKR engine. With the latter you don't need to change the lower bedplate, which saves a little work (not that much though).
For some reason I found this thread in the S-Type section, i've moved it to Jaguar Engines & made it a sticky....
Also worth putting in a link to this thread here https://www.jaguarforums.com/forum/x...-thread-61113/
Also worth putting in a link to this thread here https://www.jaguarforums.com/forum/x...-thread-61113/
I currently have a 2000 XJR which as everyone knows are known for the timing chain issues and the weak A drum in the transmission. Has anyone done a drivetrain swap from say a 2004 XJR into say 2000 XJR. The reason I ask is because from reading it looks like the newer drivetrain is much better all around and I don't mind taking the time to try something like this down the road. I am sure the computer and harness will have to be swapped but is it even possible? My car runs fine now but it's an idea I have been pondering as I am in California and not sure I can piece together the two blocks and still pass CA SMOG laws.







