doomi

Well, I took a wrong turn last week and somehow ended up in Mexico with a new Mustang revving at me. I took the bait and easily put him in my rear view mirror, but now have a concern.

When I ran him my car smoked pretty badly from the engine bay area. I don't believe I over-revved and everything sounds fine. I pulled over to check it out and see that quite a bit of oil had sprayed on the exhaust, causing the smoke.

Since then I've had a light leak when driving normally. I've tested going into high RPM several times since then and sometimes it leaks considerably and sometimes it doesn't.

There's enough oil everywhere that I can't trace it. Does anyone have a starting point?

Patriot Six

Check the oil pan. You’ll need to get it up on a lift and see where it’s coming from, but an oil pan leak will leak onto your exhaust and cause smoke to come out from under the car, especially at higher RPMs..

doomi

I had it on my lift over the weekend and cleaned it all up. It was so messy I couldn't trace the leak. I need to put it back up there to see what's what. While it's on the lift I'll torque the oil pan bolts to spec.

Honestly I thought the high RPM trigger would rule out the oil pan.

Patriot Six

Not necessarily. You may have excessive crankcase pressure. Are you running a catch can?

doomi

I just got it off the lift and the oil is everywhere again. I'm going to need to do an undercarriage wash then come straight home and look.

I do not have a catch can.

xBoostx

Is your valve covers remove the driver side cover and you'll see why is going on the exhaust, connect your driver side valve cover rear plugged breather to the air inlet like the right side do not T the two sides.

Ahrmike

oil filter leaky? I wonder if you have a double-gasketed filter? Also possible your oil cooler lines are leaky if you are so equipped.

doomi

Not sure I'm following, but I'll pull the valve cover and see if I can find when your talking about.

Its been several thousand miles.since my last oil change but I can still check for a double gasket. And good thoughts on the oil cooler lines. Mine is z51 equipped.

Thanks for all the suggestions everyone!

CI GS

I had the same experience when I stupidly installed my front crank/harmonic balancer seal backwards, which caused the lip of the seal to get torn. It didn’t leak at idle or parked, but when I blasted it to WOT, the crankcase pressure would push the oil out and it sprayed everywhere under the car. I only realized it was leaking when noticed the blue smoke in the rear view mirror coming out the back during a run. The whole underside of the car was coated with a oil film. I would check behind the balancer to see if it’s wet with oil. If so, most likely the seal is bad or has worked loose somehow.

doomi

Good thought. When I was under there last night I noted there is oil midway up the engine, so I think that probably rules out the oil pan as a major leak.

When I had my cam installed a few thousand miles ago they replaced the balancer. Now I'm curious if he put the crank seal on backwards.

How did you figure that out? I'm a little uncomfortable putting the car on my lift then having someone floor it while I'm under there to see where it's shooting from.

extrapilot

Check the area above the oil filter, were the pan bolts up to the block.
This area is under full pressure and a possible leak there.

doomi

I torqued those bolts to spec last night. I'll thoroughly inspect the area when I get it back on the lift.

Thanks for the info!

CI GS

I just stuck my finger behind the balancer and felt some oil pooling there, so I knew it had to be the seal gone somehow. I had to pull the balancer off before it could assess what went wrong. When I pulled it off, I saw immediately that I had installed it the wrong way around (with the sealing lip pointing outwards) and the balancer snout had ripped the seal as well. But even with a chunk of the seal missing, it didn't leak noticeably until I blasted the car and the oil blew out and got onto the exhaust. I had just done a cam change as well. The worst part was that I'm running the "blower snout" IW balancer, which carries a larger seal, so I had to end up ordering a new one (and a spare) from IW, because I couldn't find it anywhere else.
EDIT: Please note that even if the seal isn't torn, but installed the wrong way around, it will probably allow oil to escape once you build crankcase pressure at high RPMs, because the seal is designed with a lip that uses pressure to press that lip inwards to enhance the seal around the balancer hub. So, if its installed backwards, it will instead allow the lip to blow away from the hub, thereby allowing oil to bypass the seal. Unfortunately, there's only one fix for that, and it involves tearing down the whole front of your engine again, and removing that damn steering rack. I managed to figure out an "easy" way to completely remove the rack though, so if you figure out its the seal that's leaking and need to pull it down, let me know.

rsb213

Check and double check the valve cover gaskets and the bolts that secure it down. Mine are currently leaking at a small enough rate that I'll get to it when I get to it but it drips on to my passenger side header.

doomi

I appreciate the replies. They're all helpful whether or not they fix my leak. Now I know areas to keep an eye on.

I'm tired of being under the car for now so I'm going to give it a few days and look again.

xBoostx

Before you go under the car take a paper towel and swipe it across under the valve cover above the header flange see if it comes out wet.

doomi

Just checked both sides. It came out dirty, but not wet.

And no evidence of oil on the headers.

hrt vlv

Have you considered dyeing the oil and use UV lite to narrow down or locate the leak. It will not harm your engine.

doomi

I have considered dyeing the oil, but there's so much down there I wasn't sure how well that would work. But there's really no reason not to try after I clean it up as much as possible.

doomi

I finally have a chance to get it to a local shop. When speaking with the owner he mentioned that I should order a Catch Can for him to install and that it will probably fix the oil leak issue.

I'm concerned by this because I have not made any changes to the car that would have increased crank case pressure. It just started leaking like this after heavy driving. So this seems like a band-aid instead of addressing the issue.

I can throw a catch can on there myself, but I'm still concerned that there is an underlying issue that needs to be addressed.

What are your thoughts on this?