Hello all. I am new to the forum and have been reading many posts. I have a few questions that are not addressed in other posts.

The situation:

We have a 2003 Discovery II with 107k miles. We have owned it for 4 years (had 45k miles when purchased). Since we have owned it, I have performed regular maintenance (oil/filter every 2.5k miles, plugs / diff fluid changes / tranny filter and fluid, flutter valve+wheel hub for 3 amigos, window lifts, door locks, headliner, etc.).

It developed a mechanical ticking sound (frequency about half of the engine speed). The local dealer changed the exhaust manifold gaskets and exhaust downtube gaskets. They also changed head gaskets as there was some coolant leak. The ticking sound remained, so they did an oil pressure test and found 12 psi hot at idle. The oil light on the dash has never come on.

I took over and replaced the oil pump. The ticking remained when hot (mostly at idle). It seemed to disappear with higher RPM (oil pressure related). It appeared to be loudest on the passenger side rocker arms closest to the radiator. Next I replaced the lifters / pushrods / rocker arms / rocker arm shafts. The old rocker arm shafts appear to have wear (about .002 less diameter in the location of the rocker arms, wear on the bottom of shaft) and the rocker arms appear to have wear in same location (hard to measure out of roundness of the rocker arms).

After replacement of these components, the oil pressure is as follows:
Cold idle / 2000 rpm: about 50 psi --> good
Hot idle: 12 psi --> OK?
Hot 2000 rpm: about 40 psi --> good

The RAVE manual states >10 psi hot idle is OK. I remain concerned that there is rod bearing wear, as there is a very slight knocking when reving from idle to 2000 rpms and the oil pressure seems a little low.

I need the truck as a reliable daily driver and want to make it right (short of pulling the motor).

Now for the questions:
1. Would you be concerned with the 12 psi hot idle?
2. Would you replace the rod bearings (appears straight forward with motor in car) as they are probably worn and it would address the slight knock and raise oil pressure?
3. Would you replace main bearings when doing the rod bearings? Can these be done with the motor in the truck?
4. Should I anticipate that cam bearings will need to be done as well?

Really appreciate the assistance of this forum as the local dealer appears to have limited experience with this level of work (more focused on routine maintenance and the car wash).

Thanks.

David

 

I don't think the bearings are the issue, sometimes in these engines the piston skirts can collapse inward a few thousandths and then they rock in the cylinders when the engine warms up making a rapping sound. I can't be positive that this is your problem but, it could be.

 

Also, have a look at this...

http://robisonservice.blogspot.com/2...-failures.html

 

David, what weight oil and what oil filter are you using.
By the way, the oil light will not come on till around 6 to 7 PSI, would I be concerned, yes, just a little.
Have you pulled any main bearing caps yet?

 

I understood the low pressure light to be at about 6 PSI, which is why I hoped not to have a problem. The light would only come on for a few seconds at the time of an oil change (always have followed the recommended fill with oil before changing filter to keep the prime in the oil pump). Looking at the wear on the rocker arms / rocker arm shaft made me think that even 10 psi might not be a good level.

I have been using 10W40 for the last 4 years. Just put Rotella 15W40 in it (live in SC). As for the filter, I have mostly used genuine Land Rover filters. Over the last 10k miles, I have also used a Mahle filter recommended by Atlantic British.

I have not pulled the main bearing caps yet. Hoping to have all of the parts on hand when I take off the oil sump.

 

Mike,

Any input on whether the main bearings can be replaced with the motor in the truck?

 

You're going to have one helluva time replacing the main bearings with the engine in the truck. It will be much better if you take the engine out.

 

You are chasing a red herring.
Its not the rod bearings.
Its not the lifters.
Just drive it until it blows.
You have spent enough money on this thing now you could have bought a whole new engine.
Just drive it, dont worry about it and turn up the stereo to drown out the engine noise.

https://landroverforums.com/forum/sh...ad.php?t=37306

 

In hind sight, I wish I went directly to a new motor. At this point, rod bearings will only cost about $80 (same for the main bearings). Thought it made sense to chase these as the motor probably won't live long with low oil pressure.

 

I have a few friends who have some experience on older GM motors. They walked the main bearing around while it is still in the motor. Do you have direct experience with trying this approach on the Rover V8?