I have a 2003 disco s. When you first crank it up cold it sounds fine. If you put it into drive and give it gas you can hear a tapping coming from the engine. Once the engine warms up you don't ever hear it again. It usually takes about 5 mins from starting it to get the tapping to go away on engine accel. I don't remember hearing the tapping when I bought it. I changed the oil and filter after I bought it and shortly after that is when I noticed the tapping. I used a mobil 1 filter and 15w-40 rotella. The oil that was in the engine was pretty old and dirty. The tapping sounds to be at half the speed of the engine rpms but it may not be. Bad hydro lifter? Suggestions?

 

I pulled both valve covers, rocker shafts and push rods.. Didn't see a thing wrong with any of it. All the more reason I'm thinking lifter now...

 

Well first I would not use diesel oil in a vehicle that requires only 5w30.

Secondly you can fix lifter noises with marvel mystery oil instead of throwing parts at it before going into it.

 

Good point. Maybe the oil is too thick cold and isn't flowing enough to get the problematic lifter going until the oil gets hot and thins out.. I thought people were using rotella t in these with no problems? Either way I just bought the thing and I wanted to make sure i didn't have a bad rocker arm as I keep hearing about. I at least know that all that is good and I can now fix the annoying valve cover leak that's keeping my driveway lubricated. Btw I don't recommend to anyone to ever volunteer to work on someones disco if it has SAI. Omg what a pain in the *** to do a tune up on...

 

My suggestion would be to first see if your 03 is on Rover list of possible engine/oil pump failures, if it isn't then leave it at a good shop over night and have them check the oil pressure when cold at idle and 2000 RPM's, again when warm at idle and then at 2000 RPM's. You will find the problem pretty quickly and quit driving it till this is done.

 

I don't have 400 bucks to pay a diagnostic charge and test... I will do the oil pressure check myself... As soon as I figure out where to tap into.. I'm guessing to remove the oil pressure switch? Although I don't see the point.. If the pressure is good hot then it sure as heck is good cold... Shrug. I will check however. And no it's not in that vin range. I'll let you know as soon as I get the engine back together.