Now I need to find out where a significant oil leak at the rear of the engine is coming from.
Hughes stud girdle, windage tray and Milodon pan. Lakewood with block plate.
K-frame is off, as noted in the thread about steering box removal. Easy access. Waiting for new T-bars anyway.

The block plate for the Lakewood has three 1" holes in the front, below the pan, and there does not seem to be any oil in there on the engine side of the flywheel.
Could be: between the block and girdle; girdle and windage tray; windage tray and pan; rear main seal holder sides; rear main seal.
What's odd is that oil drops also collect on the heads of the two bolts (the rest are studs), and I can see light reflect off some oil at the line between the stud girdle and the block plate.

It'd be easy to drop the pan and windage tray without the K in the way, so I'll probably do that.
The rear main seal can't be seen with the girdle on, but removing the stud girdle won't be fun lying underneath it since all the shim packs will want to fall off...

Also: I have a lot of oil in my MP valve covers (think I may need to restrict it since the cam has a groove in the journal). There may have been oil leaking from the rear of the right valve cover and tracking down along the block. Fresh clean oil is hard to see... I have removed and re-did both valve cover gaskets.

Now to start up the beast in the garage and let it run for a few minutes. Hoping to see where fresh oil (if any) is still coming from. Crossing fingers it was that valve cover, but I never get that lucky...

Any thoughts?

Oil pressure switch or gauge line which ever you a re using.

Clean the rear of the block from the heads down to the bottom of the oil pan to help identify where it is leaking from and then use a little bit of baby powder or flour sprayed onto the back of the motor on the outside of the heads down towards the oil pan to see where it starts sticking

If you have a nearby Auto Zone, they sell Fluorescent Leak Detector Dye, and also will loan you (with a deposit) an ultra-violet light to view it. You add the dye to your crankcase, run the engine, then use the light to see where it's leaking.

Oil pressure line, no sender. The other port has a gauge screwed into it, so I can watch the pressure while under the hood.
Definitely dry in that area.

Cab, thanks for the tip about using flour! Everything's pretty clean, it's a new engine with only cam break-in time (and a whole 0.3 miles on the Autometer speedo)
I should be able to run my fingers behind the heads after running for a few minutes, and make sure it's dry, too.

If I do have to get to the rear main seal, I may not put the girdle back on (with my ported iron heads I won't be making over 500 hp anyway, at least without nitrous). When I have my bare aluminum heads worked by Dwayne, then I'll be near 600 hp and I can go through the trouble of re-shimming the girdle from underneath.

My other half is going to love it when I fire the beast up in the garage

I've had a cold for a couple of days, so didn't feel like firing it up. Today I got underneath and dropped the pan, and removed the stud girdle. Super easy with no K-frame or steering

It was immediately apparent that there are big leaks (especially in the rear!) between the pan gasket and the girdle, AND between the girdle and the block. What I can see of the rear main looks fine and there's no oil on my finger when reaching through the Lakewood block plate vent holes.

I was surprised not to see a windage tray (I built this engine something like 13 years ago...) I think it interfered with the studs, or something. Anyway the Milodon deep pan has a good baffle, and looks like it'd keep just as much oil away from the crank, especially in combination with the girdle.

The oil pan gasket is firmly attached to the pan with Permatex Aviation form-a-gasket and doesn't look like it leaked. But I can see distortion where the nylock nuts (supplied with the girdle) dented the stamped pan.

More critically, and I'm again not sure WTH I was thinking back then, instead of RTV I'd used Permatex #2 also. To make a long story short, it didn't work everywhere... I guess the girdle is not quite as precisely machined as I'd thought - ditto the block rails!

Anyway I'm going to clean up all the Permatex with alcohol, then put it back together with RTV like the instructions said in the first place
AND a Superformance pan gasket that is on order. It may not come before the weekend and I'm out of town next week for business, but I hope to have a favorably dry report soon

ETA: 91% isopropyl alcohol only works on fresh Permatex #2. Nothing else makes a dent except lacquer thinner. I ended up using a gasket scraper and a rubber mallet to clean both the block rails and the gasket which I'd REALLY stuck to the pan. Also used a small ball-peen to make the pan holes flat again. [u][And/u] ordered the $45 AR pan reinforcement set. I hate oil leaks!

I use AN flat SS or steel washers under all of the bolts or nuts I use on engines to help prevent distortion on sheet metal and tearing up cast aluminum parts

Good idea...

Although Hughes' stud & girdle kit did not include them or call for them in the instructions
Anyway I thought I'd been careful with tightening them. Maybe not

Andy's pan rail reinforcements are 1/8" thick so that should be that!

Although the seal is not leaking, I am thinking of pulling the seal retainer and #5 main cap, and redoing the side seal(ant). It'll never be easier to get to than right now...

I did not use the side seals at all, just operating-room clean on the holder and block and filling with RTV. Also added RTV on the outside where the holder tapers to the block. Can't even remember if I used blue, red or black (and can't see it with the main cap and holder in place).

Pro: can use new Ultra Black, or Ultra Copper RTV (the most oil-resistant of all).
Con: May not be able to get the sides and parting-line area of the block super-clean with the engine and trans in the car.

So I'm waffling as to leave well enough alone. But I'll be really pissed if it starts seeping when I actually get to take a few cruises!

Thoughts?