2.3 '96 Leaking/seeping oil

[LittleJohn]

I changed the oil and filter almost immediately after buying the truck in June, so I don't know if it was leaking before. I tightened the drain plug just a little bit more and snugged the two small bolts on the plate behind the drain plug and I know they are not leaking. I sprayed the underside off as well as I could to try to identify where the oil is coming from, but have not yet been able to see it actually happening. This leak is bad enough that if I pull it into the garage to work on for 4 hours, there will be three good sized spots all dripping from around the drain bolt area, but they are all separate and dripping off some other places.

The entire underside of the engine towards the front of the truck has a film of oily grim and I'm considering tightening the under engine bolts but really don't want to screw up the gasket. I know that leaks from the gasket between the engine and transmission are somewhat common, but it really doesn't appear to be coming from there.

The amount of oil I have leaked out in the three months I've parked it on the street is borderline EPA violation and I really feel like I need to fix this.

Currently using Castrol High Mileage 5w-30.
The truck has over 200,000 miles ODO broken so not certain.

 

[Mark_88]

Two other places that might be a source that may appear as coming from the oil pan or drain plug...

the valve cover

The cam gear bolt

If you have recently replaced the timing belt and removed the cam timing gear the bolt can leak around the shaft and works its way down the front of the engine and can also be blown around by the fan if the timing belt cover is off...I put a layer of thread sealer around the shaft of the bolt near the top of the thread...there is a seep hole that you don't want to cover over but other than that the sealer helps keep the oil from leaking from the top of the engine.

The valve cover usually drips down the back of the engine but can drip down any part of it if the cover was removed or has been loosened recently.

Other than that...the drain plug does have a washer that needs to be replaced periodically. If that washer is missing or too old it will allow the oil to drip...drip...drip...

 

[tomw]

I would have bet on the cam cover seeping from all sides. Check also the front seal around the crankshaft.

One thing to consider is that you may need to clean the PCV valve and/or the connecting hoses and port into the intake. With 200k miles, the valve may be sticky or gummy, and not sealing, or not flowing as well as possible. With the flow restricted, you can pressurize the crankcase a bit, which will tend to push oil out the easiest way, along with any gases that can be expelled.
Look on the engine for 'clean' spots, where the oil leakage is enough to wash off the dirt that gets in contact instead of making it stick to the side of the engine. If it is 'clean washed', follow that trail up, against gravity to find the source.
tom