Oil Leaks
 

Well when it rains it pours. I have a LS400 93. I've checked for this kind of problem but couldn't find anything.

I did the famous Sea Foam procedure the other day, a third in the oil, a third in the gas tank, and a third in the PVC valve. After the smoke was gone I changed the oil and filter using a synthetic oil. Never had a oil leak before.


Took the car for a ride and then checked for leaks, well guess what I have a leak. It was all over the bottom of the engine.

Took the car to a trusted mechanic, he said it was hard to tell where it was leaking from due to not being able to see certain areas of the engine. He doesn't have the ability to tear down where he needs to be able to see where its leaking. He said it maybe a head casket. Where else can it be leaking? Especially after using Sea Foam.

Can you guys help with suggestions as to what maybe the problem?

Thanks:

First off, nothing wrong with using Seafoam. It may have loosen oil sludge but if your car was previously leaking, it may just be a seal or gasket that needs changing. I doubt its the head gasket.

And keep in mind you are using synthetic oil, which will pass through much more easily than a heavier weight conventional. Best thing for you to do is very safely, clean your engine bay, don't forget to cover all electronics, use compressed air to blow off your alternator and sensors (not the AFM/MAF of course) and wait for it to dry before starting up.

Then watch very very closely where it's leaking. Or alternately, the more expensive route, buy some UV additive, add to your oil and watch it leak out from there.

you said you changed your oil? right after right ? my quesses would be on a double gasketed oil filter , loose oil filter, and or loose drain plug because avalon42 said its not likely for sludge to cause this especially right after changing your oil also

I checked the oil filter and drain and so did the mechanic, the leak is somewhere up higher than the filter and drain plug.

Most likely you have a leak at the rear main oil seal. When you loosen up any loose sediment with the Sea Foam, you may have loosened any sediment which may have been clinging/built up around the seal over time preventing any leaks. Rear main seal leak is a common "to be addressed" problem with the older cars as the seals don't last forever.

good thing the rear main seal is so easy to check hahahahahahah

You say rear main seal? Where is it? does the engine have to be pulled?

The rear main seal is sandwiched in between the crankshaft and the oil pan. I don't know about the LS400 but I know in most cases the engine does have to be pulled because sometimes the crank has to be removed. All depends on how much room you have and I've never torn into the 1UZ-FE.

The rear main seal on the LS is where the engine and transmission meet down low. Easily seen from below the vehicle. If it needs to be replaced, the tranny needs to come out, not the engine. It isn't that difficult a job for a mechanic that knows what he's doing.

If it is the rear main seal, your mechanic should have easily picked up on it...

How bad is it leaking?

the rear main seal isnt going to cause oil to be all over the bottom of the motor as it will blow backwards not forward...

depends on how bad its leaking, most of the time the only symptom is a very small amount of oil seepage where the trans and engine meet.

Its leaking alot, the whole bottom of the engine is wet.

you're SURE its not the oil pan seal...

I was under the car and didn't see anything coming from the oil pan.

Oil Leak
 

What other parts could be leaking besides the main seal, oil filter and oil pan?