questions about engine knock...
#1
questions about engine knock...
ok guys...i have a 03 discovery (in the bad VIN range) with 101,000 miles on it. in the last couple of weeks it has developed a knock in the engine. so far i have received no warning lights, including oil pressure. ive maybe put 50 miles on since the knock started, and will not be driving it again till i get it to the shop. my questions are, what should i have my local shop look at? im assuming that since this is one of the disco's that may have a faulty oil pump that i should have the oil pressure tested. how about having them check for an exhaust leak? are there any other things that could be causing this knock? and if the oil pressure test does come back bad, would it be a safe assumption that this is why i have a knock? and, in theory of course, if i have bad oil pressure, would i be safe in just purchasing a oil pump repair kit for it, or do i need a whole new oil pump? i know i can purchase the repair kit for about $130 although im not sure what i will end up spending in labor. i appreciate any help guys!
#2
ok guys...i have a 03 discovery (in the bad VIN range) with 101,000 miles on it. in the last couple of weeks it has developed a knock in the engine. so far i have received no warning lights, including oil pressure. ive maybe put 50 miles on since the knock started, and will not be driving it again till i get it to the shop. my questions are, what should i have my local shop look at? im assuming that since this is one of the disco's that may have a faulty oil pump that i should have the oil pressure tested. how about having them check for an exhaust leak? are there any other things that could be causing this knock? and if the oil pressure test does come back bad, would it be a safe assumption that this is why i have a knock? and, in theory of course, if i have bad oil pressure, would i be safe in just purchasing a oil pump repair kit for it, or do i need a whole new oil pump? i know i can purchase the repair kit for about $130 although im not sure what i will end up spending in labor. i appreciate any help guys!
You'll get opinions, but here's the fact (as I know it) regarding the bad engine crap.
Some motors (commonly installed 2003) had alignment dowel pins for the timing cover/ oil pump machined into the engine block incorrectly.
The timing cover, when tightened down, stressed the housing causing it to fail, (crack)over time, after which the loss of oil pressure caused the engine to fail to varying points.
The only remedy that LR recognized was a new engine (they had to warrantee)
If your timing cover/oil pump has failed, but your engine hasn't, I'd throw a new cover/pump ***'y on it and drive it another 100k. (probably)
B/4 doing anything, I'd get your existing oil pressure checked.
Knocks could be from several sources, not only the oil pump failure.
Is it a knock or a tick?
Is the knock/tick consistent or louder under load?
Does it disappear under load?
Does it knock/tick more hot or cold?
more info please, and please let us know how it turns out.
luck,greg
#4
well the rover is at the shop as i speak having an oil pressure test completed. today was the first time i have drove it in 5 days. my shop is literally across the street from me. no knock on my drive there so im assuming it starts once the engine is warm. my mechanic popped the hood and listened to the engine a bit and right away said "im pretty sure you have an exhaust leak, but that wouldn't cause an engine knock". how crucial is having an exhaust leak repaired? any idea on cost? this is going to ruin my day! the knock does disappear at higher speeds but i would imagine that the sound is just being drowned out by engine noise. i will follow up again once i get the results of the oil pressure test.
#5
#6
#7
What were the readings? What "loose bearing"?
The oil pump gears can break and cause a knock while still putting out good oil pressure. If this is not a Rover guy, do not pay for bearing replacement until the front cover is pulled and the gears are inspected.
You should not have to replace main bearings unless you have an oil pressure problem. The oil pressure should be tested cold idle, cold at 2K, warm idle and warm @ 2K.
The oil pump gears can break and cause a knock while still putting out good oil pressure. If this is not a Rover guy, do not pay for bearing replacement until the front cover is pulled and the gears are inspected.
You should not have to replace main bearings unless you have an oil pressure problem. The oil pressure should be tested cold idle, cold at 2K, warm idle and warm @ 2K.
#8
first - put your location in your profile so we can better help you with a good LR mechanic.
I am not sure about the "knocking" oil pump but that sounds hopeful. Easy fix there.
If it is a "loose bearing", I doubt simply replacing them will help. A loose or spun bearing equals rebuild time. The crank musk come out for proper measuring and/or turning.
You can have a knock and still have okay oil pressure - especially at speed.
Be sure it is not an exhaust leak. They can sound terrible (like a rod bearing) but are easy to fix. They can leak at the head, manifold crack or at the connection to the exhaust.
As mentioned - take it to a Rover mechanic (but not the dealer!)...
I am not sure about the "knocking" oil pump but that sounds hopeful. Easy fix there.
If it is a "loose bearing", I doubt simply replacing them will help. A loose or spun bearing equals rebuild time. The crank musk come out for proper measuring and/or turning.
You can have a knock and still have okay oil pressure - especially at speed.
Be sure it is not an exhaust leak. They can sound terrible (like a rod bearing) but are easy to fix. They can leak at the head, manifold crack or at the connection to the exhaust.
As mentioned - take it to a Rover mechanic (but not the dealer!)...
#9
morzi41, any "decent mechanic can find an exhaust leak in a minute or so. (and be more than "pretty sure").
as for knocks,ticks,etc. Some of us use a stethescope, some use a piece of rubber tubing to our ear, some use a rod, but almost all of us try to localize a noise to a given area.
Your mech should do this to isolate the "knock" - Is it the oil pump?(I doubt it)
bearings in the bottom, maybe, but the stethescope will confirm, lifters - easy to confirm, exhaust leak - silly easy.
Point being, make him show you what's knocking B/4 you pay anything.
luck,greg
as for knocks,ticks,etc. Some of us use a stethescope, some use a piece of rubber tubing to our ear, some use a rod, but almost all of us try to localize a noise to a given area.
Your mech should do this to isolate the "knock" - Is it the oil pump?(I doubt it)
bearings in the bottom, maybe, but the stethescope will confirm, lifters - easy to confirm, exhaust leak - silly easy.
Point being, make him show you what's knocking B/4 you pay anything.
luck,greg
#10