Hi. New to the Rover thing. Just picked up an 04 D2 on Friday where the oil pump blew up. I'm going back and forth on whether to replace the engine or rebuild the engine.

As I've been researching different options I've come into a few things that are a little cloudy.

1.) Is a Pre 99 GEMS crank the exact same as a 99+ Bosch crank?
2.) Is a 99-02 P38a Bosch 4.6 a direct fit for a 03-04 D2 Bosch 4.6
3.) What is the difference on the timing/oil cover for the 99-02 vs 03-04?

From what I've researched that answers are 1,) Yes 2.) Yes 3.) Oil port needs to be blocked for oil cooler.

Thanks ahead of time. Can't wait to take this beast for a spin someday soon.

 

I believe those answers are correct. The GEMS and the Bosch used a different crank positions sensor mounting and trigger so on a GEMS engine you will need to use your current setup which will require some fabrication. As for the oil ports, you can block them, use one to install an oil pressure sensor and block the other, or just grab the oil cooler from the donor truck and install that in yours. ANother thing to be aware of is the SAI. Your truck should have it so make sure you use a set of heads that are for SAI.

 

Thanks for the quick reply. Yes i do have the secondary air. Got the truck home at 9 pm and we had the engine out and torn down by 4:30 am. Not exactly sure what happened but the oil cover was non existent and the timing chain broke also. Pistons barely tapped the valves and one is bent. I'm leaning towards a 99-02 pullout because for some reason they are way cheaper than 03-04's and I'm worried about doing a rebuild on the old block as I can see it starting to nickel and dime me during the process.

 

The broken oil pump probably took out the timing chain. As for the 99-02 motors from the P38, I'm convinced that they are a better motor than the later 4.6's in the Discovery. It seems that the molds were in better shape and the casting is of better quality. I'm basing this on the types of issues of seen reported for the earlier 4.6's versus the later ones. Certainly, if you are set on getting another block and there is a price advantage it's a no brainer. You will be looking at a full rebuild no matter what.

 

the newer ones lacked an oil cooler, so the oil got worse over time.

 

Well got a motor heading this way. $2135 for a 99 Bosch 4.6 with 113k on it. Was about the best deal in the state that I could find with a warranty.

I've got another question. The previous owners "mechanic" friend pulled the oil pan to check out the damage. Instead of unbolting the crossmember he cut it. What is the brace called that goes from frame rail to frame rail?

 

are you talking about the frame support brace that has 4 bolts on each end into the frame rails.

 

its just a crossmember...there are 2, one under the t-case and the other under the oil pan...grab one off a D2 in a junk yard...dont sweat it too much if you have to go without it for a little while until you find a replacement...there are plenty of people here on the forums that have removed the front one so the prop shaft doesnt hit it with a lift and articulation...some put blocks, others remove it all together..havent heard any horror stories

Take a breaker-bar and electric impact gun with you when you go to get one off another D2...most likely rusted and the bolts will snap. Check how your bolt holes are on your truck...might be why he cut it but cant imagine...and i believe its a 10mm bolt (use a 6 sided impact socket)

Add the oil cooler, not sure why they deleted it but i put one on my 4.6 and it brought down my oil temps by 10F...most certainly isnt hurting anything.

 

I have a junkyard looking to source the parts. Tried searching eBay but wasn't sure what the piece is called to search. He tried to remove it as the headed are all jacked up. We will cut the heads off or something and then replace it. Good to know its not a deal breaker without it for a bit.