Help me with my 2003 Discovery!!!!!

[dzd300]

Hello fellow Land Rover enthusiasists. I currently own a 2003 LR Discovery 2 SE. I bought this truck in Dec. of 2010. This past june i was driving, and heard a tap coming from the engine. I immediately took it to my mechanic. After some testing he discovered that the cause of this was low oil pressure. He then decieded we should start off with replacing the oil pump, $600. This did not resolve the issue. He then returned the pump to vendor thinking it may be a bad one. Once again replaced it. Same senario. No oil pressure. We then decided to tow it to my local LR dealer. After a couple of days they informed me i needed a new engine, cost $14,000. What a joke that is. They would not cover a thing with this engine at 57,000, why would i pay that much for a new one. Three weeks or so go by and I find a independent LR mechanic 60 miles away. I decide to give him a shot at it. He thus far has replaced a radiator, thermostat, hydraulic lifters, rocker arms and a few other things! He has done so much, I can't keep track anymore He has performed a block test, which was fine, ran a cleaner through to pistons to determine if they could have been causing the tap and dropped the oil pan and inspected it, everything in there was clean as a whistle! He has never come across a LR that he couldn't fix, he is totally stumped, this may be the first one he can't figure out! After all of that, it is still TAPPING! The previous owner followed all of the recommended factory maintenance, all of which were done at his local LR dealer, I have the service records to prove it! So after 3 months, and God knows how much $$, I am no closer to having my truck back and running properly. Any and all input would be greatly appreciated!

 

[Disco Mike]

It is good to see there is someone out there stimulating the economy, besides the President and not getting any where.
Stop wasting your money. If you want some help, with results then send me your number and I'll call you
Guessing won't fix this, testing will.

 

[dzd300]

It is good to see there is someone out there stimulating the economy, besides the President and not getting any where.
Stop wasting your money. If you want some help, with results then send me your number and I'll call you
Guessing won't fix this, testing will.

Yes, that is a good one, just the way i feel. Keep spending!

 

[wolf]

Re: help with engine oil pressure issue

Hi there;

I would listen to Mike on this problem and all I can add is that when you replace a LR V8 oil pump it is most advisable to make certain that pump is primed properly or your motor will suffer for it: i.e., a sort of 'air-lock' can be set up in the new pump and it will neither draw oil in or pump out (engine rebuilders in the UK have warned novice LR V8 builders about this potential problem - repeatedly - so I am guessing there is something to it). In my recent rebuild - I made certain I had that pump brimming full of assembly lube (as recommended by some very experienced rebuilders), another recommended lube is simple vaseline loaded into the new pump before re-assembly (remember, it is also adviseable to have your oil changed within 1000 miles after a replaced pump and/or rebuild owimng to the fact that new metal filings and assembly lubes need to get cleaned out).

Anyway, if the original problem was low oil pressure from a worn pump odds are that the newly installed pump was not faulty but, instead, launched improperly on an unpromising and short career with a 'lock' in it.

Other issues could include a dropped cylinder liner but you would get other symptoms from that as well (i.e., such as loss of coolant, etc.)

 

[dzd300]

The tapping only starts when the vehicle is warmed up, about 10 minutes after cold start up. The tapping goes away once I accelerate or rev the engine over 1000 or so rpms. Just about everytime I'm stopped in traffic or at a light, oil light flickers and the tapping starts. The mechanic thought he had problem solved, he drove it about 500 miles and said it did not tap. I picked it up (almost 4 month later!), drove home 60 miles, and as I pulled it into my driveway it was like nothing was ever done, the exact same tapping at a warm idle! The truck went back to the mechanic a week later and now a month later, there it sits. He is now going to check fuel injectors and valve springs. I have attached the bill of what he has done thus far. Any input would be greatly appriciated. Winter is coming and I need my truck back!!! $3000 and about 5 months later and I am still in the same boat as when this all started!

View attachment LR bill.pdf

 

[alzerom]

Are you sure it's coming from the engine? How about using a stethoscope or other listening device. You haven't given us the frequency (120 beats per minute) or the volume nor compared it to something we are all familiar. I've had electrical systems tap, relays can tap (chatter), a creaking dashboard can sound like a tap, broken motor mounts can tap at certain engine rpms... everyone (including me) assumed it's motor related and you have practically rebuilt the car. Stethoscope time.

Wolf had a good thought there, and Disco Mike can be helpful with the offered phone call.

 

[dzd300]

Sounds like a typical valve tap coming from the top end, passanger side. I don't have the truck to find out taps per minute, but pretty rapid and constant while at idle. Sounds like a pen being tapped on a desk. Thanks for taking the time out to help with my problem!!

 

[alzerom]

I assume you've had your head in the engine compartment rather than behind the steering wheel. You've done everything else so it's valve train time all the way from a wobbly camshaft, bent pushrods, poorly seated valves, rockers not properly gapped.... you have your work cut out for you. It's almost as much work as a "new engine". I'm going to put my money on a bent pushrod. Bent so slightly that you can't see it but when you put it on a flat table and roll it... it doesn't roll straight... it flops. When it's sitting on one position there's no tap, but when it rotates a little the length changes ever so slightly and it starts tapping. Keep us posted.

 

[wolf]

Re: addition to tapping issue

Related to the last post concerning looking at the valve train - I had an intermittent tapping that turned out to be coming from a badly worn lifter/tappet that was simply refusing to rotate and lube properly anymore, or at least most of the time, thanks, in turn to a worn camshaft.

But I think we need to set this stuff aside, at least temporarily, and concentrate on why you get that low-oil pressure lamp coming on in conjunction with the tapping? On my Disco I (1997 GEMS [NAS] non-advanced evap. sys.) the oil pressure send is right on the front cover which, of course, houses the oil pump. Now, I am not certain where it may be on your particular engine but here's my thought: i.e., assuming the mechanic who did the oil-pump overhaul did, indeed, prime that pump properly before reassembly - there is still a remaining issue that can devastate the pump and pump seating-area (i.e., that portion of the front-cover in which the pump recesse is machined) and that is the oft mistake made of the pump eliptical gears being placed in the wrong way around as it is a very easy error to make - almost unnoticeable to the eye (trained or not-so-much) owing to the fact that the gears should be placed with the very sl;ight chamferred edge toward the inside/machined face of the oil-pump housing. If the chamferred edges are placed toward the pump access plate (i.e., facing back toward the engine block) then you have straight-edged metal gears that will bind on the front-cover's oil-pump housing. As you can imagine, this can cause several problems such as intermittent low-pressure which in turn could cause lifters to start tapping if they are minus their oil and/or any number of other things to start making noise. It has also been known to cause catastrophic failure of the front cover with a complete binding then destruction of the pump (thankfully, a rare happneing). So, to my mind if you are getting that light coming on with the noise I just think the starting place has to be back at that pump. If the eliptical gears were placed in out of sync (i.e., they come marked and bound in the proper sync and must be placed in the housing precisley as such) you could get similar oiling issues to what you have described.

The other thing to remember, which is a point constantly driven home by the UK experts on this motor, is that LR V8's oil properly by volume not so much by pressure and thus they all claim that our V8's do not respond that kindly to fancy uber-pricey synthetic oils of a thin viscosity. They all claim that one of the best oils is straight-ahead Valvoline 20-50w - even in the UK's winters. I am thinking we would have to attenuate that somehwat over here but I do recall that when I was down in LA, a few years back during the summer, I had a local LR expert change my oil and he put in Kendall's 20 50 w and i swear it never ran so well as then nor since (as I can't get that oil up here in the Pacific NW). All of this brings me to the question: what oil are you using? And please, don't take my word for it - talk to John Eales of JE Development/Engineering in the UK - he makes race engines out of these babies - or talk to the good people at RPI-UK as they do the same as John - and what they are going to tell you is stay away from that fancy synth stuff as these old-fashioned V8's do not, repeat, do not like it!

 

[dzd300]

Related to the last post concerning looking at the valve train - I had an intermittent tapping that turned out to be coming from a badly worn lifter/tappet that was simply refusing to rotate and lube properly anymore, or at least most of the time, thanks, in turn to a worn camshaft.

But I think we need to set this stuff aside, at least temporarily, and concentrate on why you get that low-oil pressure lamp coming on in conjunction with the tapping? On my Disco I (1997 GEMS [NAS] non-advanced evap. sys.) the oil pressure send is right on the front cover which, of course, houses the oil pump. Now, I am not certain where it may be on your particular engine but here's my thought: i.e., assuming the mechanic who did the oil-pump overhaul did, indeed, prime that pump properly before reassembly - there is still a remaining issue that can devastate the pump and pump seating-area (i.e., that portion of the front-cover in which the pump recesse is machined) and that is the oft mistake made of the pump eliptical gears being placed in the wrong way around as it is a very easy error to make - almost unnoticeable to the eye (trained or not-so-much) owing to the fact that the gears should be placed with the very sl;ight chamferred edge toward the inside/machined face of the oil-pump housing. If the chamferred edges are placed toward the pump access plate (i.e., facing back toward the engine block) then you have straight-edged metal gears that will bind on the front-cover's oil-pump housing. As you can imagine, this can cause several problems such as intermittent low-pressure which in turn could cause lifters to start tapping if they are minus their oil and/or any number of other things to start making noise. It has also been known to cause catastrophic failure of the front cover with a complete binding then destruction of the pump (thankfully, a rare happneing). So, to my mind if you are getting that light coming on with the noise I just think the starting place has to be back at that pump. If the eliptical gears were placed in out of sync (i.e., they come marked and bound in the proper sync and must be placed in the housing precisley as such) you could get similar oiling issues to what you have described.

The other thing to remember, which is a point constantly driven home by the UK experts on this motor, is that LR V8's oil properly by volume not so much by pressure and thus they all claim that our V8's do not respond that kindly to fancy uber-pricey synthetic oils of a thin viscosity. They all claim that one of the best oils is straight-ahead Valvoline 20-50w - even in the UK's winters. I am thinking we would have to attenuate that somehwat over here but I do recall that when I was down in LA, a few years back during the summer, I had a local LR expert change my oil and he put in Kendall's 20 50 w and i swear it never ran so well as then nor since (as I can't get that oil up here in the Pacific NW). All of this brings me to the question: what oil are you using? And please, don't take my word for it - talk to John Eales of JE Development/Engineering in the UK - he makes race engines out of these babies - or talk to the good people at RPI-UK as they do the same as John - and what they are going to tell you is stay away from that fancy synth stuff as these old-fashioned V8's do not, repeat, do not like it!

Thank you so much for your reply, i will foward this to my mechanic. I will keep you posted on progress. Thanks again!
Deb