waveflux

1989 928s4, driving home oil pressure light came on, stopped car, checked oil, barely a reading. Had car towed to garage, after filling with oil, it started losing it from driver side.
Car had compression and no/oil water mix, so it pointed to blown valve cover gaskets.
Water pump was leaking slightly, so...TB/water pump/Valve covers/ intake gaskets/ Oil hoses/ replaced. just got a call, oil leak is still present from driver side, seemed to be coming from exhaust manifold area.
Are we looking at a cracked block?
Car still has compression, and no oil/water mixture in reservoir.
Cam seals have been checked along with Oil sender.

Jetdriver69

I had a BMW 316 that I drove while stationed in Germany that had a serious oil leak around the exhaust manifold.

Come to find out that one of the manifold studs that snapped off. After drilling the broken stud out and re tapping, the leak was gone.

Not saying it is the same thing, but worth a look.

waveflux

Well...I'll take anything over a cracked block at this point. Otherwise all the aforementioned work for naught. ( and boatload of cash out the window )

Mrmerlin

It might be time to remove the alternator and then start the engine to see where the oil is coming from.

Since you said you had new oil lines installed there are only a few areas where oil can leak from can you provide any more info on what conditions the car was operating under just before the oil leak started?
Do the mechanics that are working on your car know the 928?

Hilton

Sounds obvious, but did they check the rubber oil cooler lines? They're on the driver's side of LHD cars, just down near the exhaust manifold (assuming by "oil hoses" you mean the breather hoses on the cam covers)

waveflux

Mercedes mechanic, he's worked on this car before but not expert ( Becoming one at my expense ) hard to find 928 specialist.
I was driving over 60 mph on interstate when the oil pressure light came on. Pulled over right after.
Yeah, oil breather hoses were replaced. The old Y shaped one had a split.
I see a vid on Youtube, suggesting cleaning engine and spraying with foot powder in suspected area.

waveflux

He did mention about 3 plugs were cleaned of corrosion, plugs and wires were done about 4 years ago, less than 5000 miles.

mike77

You can get ultraviolet dye kits with a uv torch to help trace oil leaks

waveflux

Yup, that's another method. Headed over to the shop to get a first hand look.

ammonman

Sounds like they replaced the crankcase breather lines, not the oil cooler lines. As Mr. Merlin suggested you need to have them inspect the oil cooler supply and return lines going from the driver side of the block behind the alternator to the radiator. These lines are under full oil pressure once the oil thermostat starts directing oil to the cooler. 2 bar at idle (30 psi) and you will lose LOTS of oil quickly at that pressure.

Mike

waveflux

This sounds about right. My mechanic had today off, another one let me have access to the car. I could see a slow drip on the exhaust manifold pipe. Turned the car on and it burned off at temp.
I drove it around in the parking lot for a couple of minutes and it turned into a gusher. Spilling down straight to the ground. It wasn't a pleasant sight.

Bill Ball

Although the cam covers are over the exhaust manifold and can drip oil down on them, I've never seen a "gusher" from that area. They seap a few drops here and there from a less than perfect seal. However, it's possible the seal has a major defect and could account for your substantial oil loss. The likeliest source, though, is the oil cooler lines. This would cause a high pressure gusher that would go everywhere on the driver side. Seen that happen from either a defective hose or a fractured fitting on the block. The face of the threaded hole in the block can fracture and come off with the fitting if that fitting is removed. If this is not repaired you get a leak as the fitting no longer seals to the block.

waveflux

Just ordered some new lines. Fingers crossed.

Adamant1971

You can also get lines rebuilt. I had mine done for $80. Make sure the mechanic is aware of the fragile nature of the boss on the block. Best to not disturb the fitting that's in the block, they are green loctite ftom the factory. As mentioned earlier it's very easy to crack the block if that fitting is not counter held when removing and installing the lines.
It's also much easier to remove the rad with the lines attached, so you can remove the lines from the rad easily. And you will need a bicycle crank wrench to counter hold the fittings on the rad/block. I tired doing mine with the rad in and it was extremely hard, once I had the rad out it was easy. Pics in my flicker album if you need any reference for the mechanic.

Adamant1971

Here are a couple pics.