LIM question

[perm01]

Can you leak oil from the LIM gasket?

[black05gt]

In short, yes. For more info, please use the search function, there is a ton of info on this subject

[perm01]

I did a quick search and all I found was people mentioning coolant leaks, not oil. I guess I will look more in-depth. Thanks.

[DarkOzzy1]

If you find anything with more info about it, let me know. Thanks!

[eric99gt]

In short, yes. For more info, please use the search function, there is a ton of info on this subject

In a rare case maybe but it's hardly common.

[rixGAphx]

eric is correct, that oil can leak from the V6's LIM gasket only in a rare instance, and when it happens a *few* drops of oil are sucked INTO the coolant.

There is no oil flowing thru the LIM itself, so the LIM gasket has no oil passages that can leak.
There is COOLANT flowing thru the LIM, on its way to the t-stat housing and out to the radiator. That is where the leaks usually occur.

But because of the goofy head design on the 60* V6, the valve cover goes across the head and part of the LIM.
Therefore, the LIM gasket (which seals the space between the LIM and head) is within the space where the valves and rocker arms operate.
Oil is delivered to the rockers via the pushrods, and kinda splashes around under the valve cover.
*Some* of this oil will splash onto the edge of the LIM gasket; if the gasket happens to fail just at this edge, then oil can leak into the space.
But that space is occupied by cooant at 14 psi trying to push its way OUT into the rocker galley!
Only as the engine cools, and the pressure of the coolant drops to zero (or even to a slight suction) will oil be drawn thru the failed gasket edge.

Bottom line: Oil cannot LEAVE the engine via a LIM gasket failure.
A *little* oil can enter the coolant and show-up as oily residue in the resevoir, but by that time coolant has already been pushed INTO the oil at the failed gasket location.

The larger question for perm01 is: Do you have an oil leak?
If so, where are you seeing the oil?
There are about a dozen more-common oil leak locations on the V6, and all of them show as oil on the outside of the engine.
They also leak in much greater volume than the tablespoon or two that might leak at a LIM gasket before the motor absolutely destructs from the coolant in the oil.

Hope this helps,
-Rick

[eric99gt]

I knew rick would chime it with the more detailed explanation of why this would be rare. This man knows his stuff.

[perm01]

eric is correct, that oil can leak from the V6's LIM gasket only in a rare instance, and when it happens a *few* drops of oil are sucked INTO the coolant.

There is no oil flowing thru the LIM itself, so the LIM gasket has no oil passages that can leak.
There is COOLANT flowing thru the LIM, on its way to the t-stat housing and out to the radiator. That is where the leaks usually occur.

But because of the goofy head design on the 60* V6, the valve cover goes across the head and part of the LIM.
Therefore, the LIM gasket (which seals the space between the LIM and head) is within the space where the valves and rocker arms operate.
Oil is delivered to the rockers via the pushrods, and kinda splashes around under the valve cover.
*Some* of this oil will splash onto the edge of the LIM gasket; if the gasket happens to fail just at this edge, then oil can leak into the space.
But that space is occupied by cooant at 14 psi trying to push its way OUT into the rocker galley!
Only as the engine cools, and the pressure of the coolant drops to zero (or even to a slight suction) will oil be drawn thru the failed gasket edge.

Bottom line: Oil cannot LEAVE the engine via a LIM gasket failure.
A *little* oil can enter the coolant and show-up as oily residue in the resevoir, but by that time coolant has already been pushed INTO the oil at the failed gasket location.

The larger question for perm01 is: Do you have an oil leak?
If so, where are you seeing the oil?
There are about a dozen more-common oil leak locations on the V6, and all of them show as oil on the outside of the engine.
They also leak in much greater volume than the tablespoon or two that might leak at a LIM gasket before the motor absolutely destructs from the coolant in the oil.

Hope this helps,
-Rick

I'll try and take a picture tonight of where I see it leaking. I don't have time to explain it right now. Thanks for the help.

[rixGAphx]

I knew rick would chime it with the more detailed explanation of why this would be rare.
This man knows his stuff.Been there, leaked that.



:D :D

[rixGAphx]

I'll try and take a picture tonight of where I see it leaking.Since you can see it leaking, it's not the LIM gasket.

Can't wait for pics!! :D

[angrysk8r]

Bottom line: Oil cannot LEAVE the engine via a LIM gasket failure.
A *little* oil can enter the coolant and show-up as oily residue in the resevoir, but by that time coolant has already been pushed INTO the oil at the failed gasket location.


I accidentally forgot to put rtv on the ridge in between the heads when I did one of my LIM changes. I didn't think oil would really leak out of there the way it was but after a while I did figure it out. It was leaking quite a bit too. I guess it wouldn't exactly be the LIM gasket failing that would cause that but you would have to change the LIM gasket anyways to fix the problem.

[HeyDace]

Oil can leak from the valley end seals and the distributor drive plug. It will appear as though the LIM is leaking oil.

[perm01]

I'm not able to get that clear of a picture. This is the best I can get.

[eric99gt]

Looks like an external coolant leak thats picked up road grime along the way.

[bballr4567]

Looks like an external coolant leak thats picked up road grime along the way.

X2.

Looks like its been there for quite a while.

[KhellendrosXS]

Yeppers, Dried out Dexcool mixed with engine grimd

[perm01]

The reason I'm asking is because it's lost almost 4 quarts of oil in less then 2000 miles and there's not a drop on my garage floor. The car has never leaked or used any oil untill now.

[KhellendrosXS]

Dump some UV dye in the oil and drive around for a while and use a blacklight to check for glowing spots on the engine to see if that valley is where oil is leaking out. How does the other side of the engine look in that area?

[perm01]

The other side is pretty clean.

[angrysk8r]

blue smoke out the exhaust?

[perm01]

Nope - it doesn't smoke at all.