Well,I was afraid that this would happen when I did the intake manifold gasket. It seems like my head gaskets are done.
In another thread I talked about the moisture near #7, I could not easliy identify what type of bodily fluid it was. I drove it to work today since I pul the new PCV hose on thinking that maybe if the PCV system wasn't working that may have caused the leak...tonight I got home and popped the hood. It's oil leaking from where the head and the block mate.
I guess I don't need to do any leak down or compression testing.

Found a rebuilt Vette L98 on Craigslist for $1500..seriously debating if I could get the scratch together to buy it and hopefully not have to worry about anymore problems for awhile.

I imagine a fresh L98 would run worlds stronger than my 132K motor.

there isn't any oil pressure going through the head gasket.. it has to be coming from somewhere else. possibly the valve cover gasket or intake valley.

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I'd suspect intake gaskets since you just did them...sucks, huh? Did you run a thick bead of the right stuff or RTV on the china walls and overlap the gasket slighly?

Also check the vc gaskets as suggested.

I'd try to clean it up again and locate the source of the leak, as much of a pia as it is.

Matthew

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Shit man, you can forget about looking for a replacement engine over this oil leak. You just don't have a full understanding of what's really going on here.

I 100% guarantee that your L98 head gaskets are NOT leaking motor oil between the head and block to the outside because they CANNOT. It just isn't happening. A SBC cannot and will not leak oil past the head gaskets between the head and block for two good reason. First the location of the oil drain back holes in the block and head gasket make that an impossible scenario. And secondly as mentioned these drain back holes are under no oil pressure.

Read this:

http://www.badasscars.com/index.cfm/p ... id=3/mode=prod/prd119.htm


Instead you probably failed to do a good job of sealing the front and back chinawalls of the intake manifold and block. The only sealer I trust for this task is Permatex Right Stuff. You need to lay a continous bead of sealer with no air pockets or breaks. Gasket surfaces should be prepped, dry, and immaculate. Don't even think about using those shitty cork strips instead of sealer that some gasket sets come with. Your sealer beads should look like this front and back:



In order to get a thick bead like this out of the Right Stuff can you need to remove or not use the supplied screw on plastic tip. Instead get it straight out of the can.

The sealer must overlap both the top and bottom sides of each corner of the intake gasksets. Then you need make sure to set the intake base straight down on the first shot and not shift it around to align the bolt holes once you set it down while the sealer is still tacky. If you're off start over.

What I do is straddle over the engine. I have one foot on each front tire and I bend at the waist as I lower the intake straight down. I am able to see from above the aligment of the intake bolt holes as I lower it so that I get it right on the first shot without having to shift it around once I set it down.

Use a known good calibrated torque wrench to torque the bolts to spec in sequence. Use thread sealer on the bolts. If you undertorque them with an out of cal wrench you're going to have leaks.

So look at your valve covers, front and back of the intake manifold, the distributor hole, and possibly even that oil pressure switch on the back of the block against the firewall for the source. The oil leak comes from up top and it runs down the front or back of the block (or both) along that diagonal parting line of the head and block. It then continues to seep along the same parting line between the head and the block ending up near the spark plugs to make it look as if it's leaking from between there. I've seen it first hand on my car. It was originating from my intake manifold ends.

You can also add dedicated UV leak detector dye to the motor oil and pinpoint the source with a UV light.

I agree,adding dye to the oil and checking for your leak with a blacklight is a great way to help locate the leak.

I did use Great stuff on the china wall after I dimple it to give the sealer more grip. I put it on the china wall running some up onto the heads then I placed the intake runner gaskets and put some more great stuff over the edges at the ends. I torqued it in the sequence the FSM specifies going over it twice and then a third to make sure.

If I run my finger under the lip of the valve cover it's dry.

I will try to get a pic of where it's leaking because to me it honestly looks like it's coming from the head/block mate.

I still don't know why it's pushing oil out of the oil fill cap. I must have really F'd something up when doing the intake gasket...

Jeff

It sounds like the pcv vacuum isn't hooked up to the right port. It should suck the oil vapors in through the pcv hose, so it shouldn't be pushing anything out the oil fill cap.

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It's difficult to get a good picture down there. But it does make it easier to kind of see where it's coming from. Looks like it might be coming from the back of the engine doesn't it?

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Repeat that to the front and back edges of your intake manifold to double check your sealer bead integrity.

Again check the distributor shaft hole at the base of the distributor and that oil pressure switch back there. Did you install a new paper "O" gasket on the distributor shaft hole between intake and distributor? I still would not rule out the valve cover gaskets since you can't run a finger along the bottom of the edge against the intake side unless you just installed those brand new when you did the intake and used a quality rubber set such as Fel-Pro not shitty cork ones. I don't trust cork gaskets for anything. All I use is rubber Fel-Pro.

Your other option as I mentioned is UV leak detector dye.

Doesn't the L98 oil fill cap have an o-ring that seals against the valve cover? I have not used valve covers with a cap for years so I don't remember what the stock cap had. But I've seen these become flat and brittle and leak on many cars and all it took was a new o-ring (or new cap if seal is not sold seperately) to stop the leak past the cap.