OK, this is a 4.6 in a 2004 D2 HSE that was rebuilt four-and-a-half years ago down to the bare block with new flanged sleeves.

Since rebuilt (by my son -- he got the D2 for free from a friend's father that slipped a sleeve, didn't want to spend $7,000 to repair it), it always has leaked/consumed oil, just at a rate that is more inconvenient than potentially catastrophic.

My son had it at college, and he didn't seem too interested in finding out where the oil was going, so I would just buy him a six pack of Rotella 4 quarts every year or so when it went on sale at Sam's for $60.

Now that he's off to grad school (with a Ford Focus) and doesn't need the 7 seater to haul around half the rugby team (how appropriate: Land Rover and rugby), I've inherited the D2 -- andI unlike my son, after 2-3 months I'm already tired of feeding it a quart or two of 15W40 every couple of fill-ups.

It doesn't smoke, so don't think it's burning oil. The front of the engine is dry, so it's not the timing chain cover, and there is oil coating the bottom of the pan and back thru the frame crossmember and transmission (automatic) but no single obvious leak point otherwise..

I've been running a bit of a risky experiment the past couple of fill-ups in that I have been letting the oil level run down without refilling, and what I've discovered is that the the oil loss stops right at the bottom add oil notch on the dipstick, then doesn't drop any further.

Originally, I suspected that it might have been the rear main seal (out of true?) and/or maybe rear main seal cap as my son did the rebuild "by-the-book" and used the hylomar blue stuff to seal the rear mail seal cap and the crux seals rather than say RTV.

However, given that I now am fairly certain that once it drops to the level of the lower dipstick notch it drops no further, I am going with the oil pan gasket perhaps?

The surface of the block oil pan mating surface was checked/decked when the new sleeves were pressed in (but not the pan itself).

And within six months of the rebuild we did try replacing the oil pan gasket, using a film of RTV as well on both sides of it this time but no luck in stopping the oil loss. During that gasket renewal, I did my best to see and feel whether there was any leaking from the back of the engine at the main seal, but I couldn't detect any. However, I have also opened the bell housing inspection port and felt around in there and it does feel oily (it was cleaned and dry when we originally mated the rebuilt engine to it).

The only other anomaly on the underside of note is that the oil pan is secured with only one of the two horizontal bolts at the rear of the oil pan as my son stripped one of them out when it was already mounted and we didn't want to take it off and put in a timesert to fix it (we should have fixed it the second time we had the pan off, but again lazy got the better of us).

I thought about trying another oil pan gasket, maybe this time taking out the little metal spacers in some(all?)of the bolts holes in order to get a better seal.

Any thoughts would be greatly appreciated

 

Have you done the PCV mod? Part of the design problem with the Rover V8 is the valve cover baffle plugs up over time and once that happens the crankcase gets pressurized and the pressure pushes oil out of the weak point in the gasketing system. Could be valve cover gaskets, could be crank seals, could be pan gasket, I have even seen the intake manifold gasket warped due to excess pressure. If that is the root cause, you may need to go back and reseal the gaskets after you fix the PCV.

 

Mine was like that when my rear main went, but regardless do the PCV mod 1st.

Then clean up everything, and drive maybe 15 - 20 minutes and look underneath right the bell housing / engine mating line my bet that is where you will find the oil. then you just need to figure out if it coming from up top or inside

 

Thanks for replies. Will take a look. What will the up top or at mating line bell housing check tell me about the main seal.

What's the PCV fix? The PCV is the spiraled oil separator on one of the valve covers, right? Or is it something else? (remember, my son did most of the rebuild).

Re. the low but stable oil level I am experiencing, is the lower notch on the dipstick below the RMS and oil pan gasket?

And FYI, my son moved the coil packs from the back of the engine to the front using a coil relocation kit from someone on this forum, so it is easier to inspect the backside camshaft valley gasket.

 

Search "PCV mod" and got no hits.

What should I search for?

 

Best4x4 has a thread about the PCV valve.
It's a $7 Fram part, that threads into the intake manifold, at the end of the hose.
The spiral seperator is simply removed from the valve cover tube.
Myself and alot of us have done this mod.
I'll post the part number if I can find it.

 

It is literally the third sticky down from the top of this D2 forum main page.

 

And fyi, if it's the rear main seal, it's one piece, so the engine has to come out to replace it.
And, you Can drop And remove the oil pan with the engine still in the truck.

 

@Sixpack577 you can do it by dropping the transmission too, that is how the shop did mine - it is easier and cheaper as I understand it.

@austinlandroverbill when everything is clean the oil will most likely be at the bottom of the bellhousing, the problem is leaks from up top also end up there. You can add a dye to the oil that glows under a blacklight that can help. If you get under there you will see a little round cover with 3 bolts on the bellhousing, if you take that off and it has a ton of oil on it it is likely the rear main - trust me you will know. if it is bone dry then it is more likely up top.

 

I've had the bell housing inspection cover plate off, and there was an oily film in there but not so much that it was pooling or dripping out.

No idea though if my son cleaned out the bell housing when he had the engine out 4.5 years ago. Knowing him, it would be no (he didn't clean it out).

Will make the mod, cleanup all the gasket surfaces with brake cleaner and power washer and then see what happens.

I have used dye before in AC systems but never in engine oil: there's a dye for that?