Common oil leaks
#1
Common oil leaks
My S3 V12 HE is dripping some engine oil from somewhere, but I can't put a finger on the exact spot.
The only obvious place where I can see oil coming out is from the left cam cover gasket, at the second screw from the front, on the outside.
Any more well know places where oil might leak?
The only obvious place where I can see oil coming out is from the left cam cover gasket, at the second screw from the front, on the outside.
Any more well know places where oil might leak?
#2
Looooooong list there mate.
Camcover gaskets, and the "D" seals at the rear.
Breather spout at the front of the LH head, from the gasket, and the 2 setscrews, as the threaded section for those screws IN the head are NOT blind holes, and oil seeps down the threads and out.
Rubber plug in the timing cover, RH side, just below the head gasket line.
Both camshaft alloy blocks, also known as Tappet Blocks, that bolt to the top of each head. There is NO gasket here, just a "chemical seal" and leak they do.
Oil cooler pipes, especially where they attach to the engine on the LH side, at the filter housing, and the square plate at the front edge of the alloy sandwich plate.
The drain back pipe including the 2 hoses from the pressure relief valve of the oil filter housing. Also known as the "walking stick pipe".
The lower, Tin, oil sump joint to the sandwich plate.
Oil sender units, there are 2 at the rear of the engine. The smaller one is the most common culprit.
The o/ring under the distributor can leak heaps of oi.
Front crankshaft seal, rare though.
Rear crankshaft seal, more of a weeper than a leaker.
Thats the more common places, but there are more, but as I said, they be very rare areas.
Have fun.
Camcover gaskets, and the "D" seals at the rear.
Breather spout at the front of the LH head, from the gasket, and the 2 setscrews, as the threaded section for those screws IN the head are NOT blind holes, and oil seeps down the threads and out.
Rubber plug in the timing cover, RH side, just below the head gasket line.
Both camshaft alloy blocks, also known as Tappet Blocks, that bolt to the top of each head. There is NO gasket here, just a "chemical seal" and leak they do.
Oil cooler pipes, especially where they attach to the engine on the LH side, at the filter housing, and the square plate at the front edge of the alloy sandwich plate.
The drain back pipe including the 2 hoses from the pressure relief valve of the oil filter housing. Also known as the "walking stick pipe".
The lower, Tin, oil sump joint to the sandwich plate.
Oil sender units, there are 2 at the rear of the engine. The smaller one is the most common culprit.
The o/ring under the distributor can leak heaps of oi.
Front crankshaft seal, rare though.
Rear crankshaft seal, more of a weeper than a leaker.
Thats the more common places, but there are more, but as I said, they be very rare areas.
Have fun.
#4
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Good idea ! Otherwise you'll be chasing your tail for ages. Unless faced with a gusher I tend to shrug-off oil leaks.
However, the engine oil sump gasket is a really easy replacement on a V12. Might be worth a peek. Maybe you'll get lucky and it's the main leak. Usually there are several leaks, though.
Do make sure your crankcase breather is clean. A clogged breather worsens a leak. Cleaning a clogged breather often reduces a bad leak to a tolerable level
Cheers
DD
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#5
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#6
#7
Good idea ! Otherwise you'll be chasing your tail for ages. Unless faced with a gusher I tend to shrug-off oil leaks.
However, the engine oil sump gasket is a really easy replacement on a V12. Might be worth a peek. Maybe you'll get lucky and it's the main leak. Usually there are several leaks, though.
Do make sure your crankcase breather is clean. A clogged breather worsens a leak. Cleaning a clogged breather often reduces a bad leak to a tolerable level
Cheers
DD
However, the engine oil sump gasket is a really easy replacement on a V12. Might be worth a peek. Maybe you'll get lucky and it's the main leak. Usually there are several leaks, though.
Do make sure your crankcase breather is clean. A clogged breather worsens a leak. Cleaning a clogged breather often reduces a bad leak to a tolerable level
Cheers
DD
I wanted to flush the transmission anyway, so no sweat in renewing the sump gaskets at the same time....they do sweat a little....
Oh.....A British car that doesn't leak oil, doesn't have any....
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#8
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As Grant mentioned, those oil cooler hoses are notorious. If they're not leaking at the connections, the hoses themselves will seep thru the rubber. Don't try to remove them from the oil cooler though, they usually take the aluminum threads with them. Or have a new cooler ready with hoses.
#9
Forgot one more common one.
Power steer cooler, tucked up in the area of the LH engine mount. Leaks like crazy, as the hoses turn to solid after about 5 years, and the unit itself is thin alloy, and careless hands will crack it. The oil should be a Red colour, but since very few previous to us owners ever change that fluid, so its usually Black.
Power steer cooler, tucked up in the area of the LH engine mount. Leaks like crazy, as the hoses turn to solid after about 5 years, and the unit itself is thin alloy, and careless hands will crack it. The oil should be a Red colour, but since very few previous to us owners ever change that fluid, so its usually Black.
#10
Power steering fluid was non existant when I bought the car.
Filled her up, she leaked like crazy because I overfilled.
After a while, the level went to normal and the power steering doesn't leak any new, red fluid... ;-)
The cooler itself though, is cover in oil (clean, new engine oil)....
Filled her up, she leaked like crazy because I overfilled.
After a while, the level went to normal and the power steering doesn't leak any new, red fluid... ;-)
The cooler itself though, is cover in oil (clean, new engine oil)....
#11
OK.
Spillage, doubtful, just throwing is out there.
Oil leaking out of the Tappet Blocks, down over the exhaust manifold, LOTS of smoke, and dripping onto the mount area.
Same scenario if the camcover/s are leaking.
Not much else that could get clean engine oil up onto the steer cooler.
Strongly suggest a good degrease, and wash down in that area ONLY, then keep an eye on it. DO NOT overwash that engine PLEASE, particularly the top section, inside the V and around the distributor etc is a NO GO zone. Just the area around that cooler that is contaminated.
Spillage, doubtful, just throwing is out there.
Oil leaking out of the Tappet Blocks, down over the exhaust manifold, LOTS of smoke, and dripping onto the mount area.
Same scenario if the camcover/s are leaking.
Not much else that could get clean engine oil up onto the steer cooler.
Strongly suggest a good degrease, and wash down in that area ONLY, then keep an eye on it. DO NOT overwash that engine PLEASE, particularly the top section, inside the V and around the distributor etc is a NO GO zone. Just the area around that cooler that is contaminated.
Last edited by Grant Francis; 03-23-2017 at 06:10 AM.
#12
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My new engine came with a 2 year/25000km warranty including oil leaks. It's been out once chasing a timing chain rattle(at the builders expense) .
It has a couple of weeps, one from the bolt at the left front on the head I can live with, the other was the oil pipe between the heads, a 9/16 spanner sorted that one.
Unless it sprays oil all over the place I won't be chasing it up. Cars leak oil,so be it.
Still 1 year and 10000 km left on the warranty btw.
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#13
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Oil seems to follow a couple of unwritten rules:
1. Gravity.
2. Seeking to return from whence it came, deep in the bowels of our planet.
Asphalt driveways are a better choice for owners of vintage vehicles, especialy Brit cars. Asphalt is a petroleum product. Re-oiling is a proper form of maintenance.
A. My Jaguar seeps almost no oil.
B. My Jeep does seep a bit.
C. My daughter's VW Passat "seeps" a lot. In my drive for a fix. Left cam cover
gasket included....
D. In the late 40's my T Ford was free of any oil leakage. Thanks to Red and Black Permatex!!!
Carl
1. Gravity.
2. Seeking to return from whence it came, deep in the bowels of our planet.
Asphalt driveways are a better choice for owners of vintage vehicles, especialy Brit cars. Asphalt is a petroleum product. Re-oiling is a proper form of maintenance.
A. My Jaguar seeps almost no oil.
B. My Jeep does seep a bit.
C. My daughter's VW Passat "seeps" a lot. In my drive for a fix. Left cam cover
gasket included....
D. In the late 40's my T Ford was free of any oil leakage. Thanks to Red and Black Permatex!!!
Carl
#14
#15
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#17
#18
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Well, last year my venerable old Jeep went in on a couple of recall items.
One added a detent on the shift gate??? something to do with N/S inhibition?? I never had an issue with that?
The other was to add trailer hitch to shield it's plastic fuel tank from being damaged in a severe rear end smack. Good ! And, I just may get around to splicing in a harness for the trailer lighting. But, for now, just another part to be removed to drop the tank and replace the Fuel pump/fuel levels sensor module. Son did that for me.
I was advised the rear main leaked. Will I investigate or swap in another. Nope, Ain't that bad. Asphalt drive gets weather protection.
My lumped Jaguar does not leak!!!!
Carl
One added a detent on the shift gate??? something to do with N/S inhibition?? I never had an issue with that?
The other was to add trailer hitch to shield it's plastic fuel tank from being damaged in a severe rear end smack. Good ! And, I just may get around to splicing in a harness for the trailer lighting. But, for now, just another part to be removed to drop the tank and replace the Fuel pump/fuel levels sensor module. Son did that for me.
I was advised the rear main leaked. Will I investigate or swap in another. Nope, Ain't that bad. Asphalt drive gets weather protection.
My lumped Jaguar does not leak!!!!
Carl
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bill70j (09-08-2017)
#19
I have an old Morris and have found this to be so. On the Morris forum one of the guys has a sig line that goes "Give and Englishman a car, and he will make it leak"
#20
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This is the point where many decide to take the plunge and do both cam cover gaskets, replace all vacuum hoses, repair crispy wires as needed, replace and relocate the fuel injector harness, replace throttle bushings, clean throttle bore and set throttle gaps, synchronize the throttle linkages, replace all fuel hoses, etc. Get it all over and done with. With the inlet manifolds off a whole new world opens up. Might as well take advantage of it.
Cheers
DD