Trying to figure out where this leak is coming from. Here are a couple of picks:




Now, i understand that some exhaust manifold studs could leak sometimes but i'm just not seeing it. The one on the far right does look a little wet but it does not look like it's leaking around the stud.

Without having to take everything apart, it does kind of look like the leak is coming somewhere between the headgasket and block right underneath that far right stud, however, it just seems like a very weird place to leak oil from.

The engine has 24 miles on it right now. The compression was done on a warm engine and came out to be 160/166/165/155. Just also did a leak down test on a cold engine and came out with 7-8% across the board, while it was at 13% on the engine stand.

Also, the oil leak is not visible under the car when the engine is operating, only when looking at it so it's pretty small, at least for now..

Any suggestions??

My guess is that is is coming from a cam seal and leaking down the head.

That's what i thought too, but i checked it out and it looks dry :shrug:

I too second the cam seal, but its possible the head gasket did not seal. The only stud that should leak is the middle bottom, as it is drilled into a oil passage.

There is a small set screw for the balance shafts cross drilling, below in the area usually has an allen head top or philips head top. Couldnt imagine anyone removing that for any reason but its the only place I can think of other than the head being loose and leaking out the oil drain ports. Or valve seals but doubt that.

ACTUALLY did your dipstick ever fly out?

It appears your manifold to turbo gasket was leaking too

My guess would be the head gasket. You should not have that high leak down #s on a fresh motor.

This is a pic I saved from Bogus on here and it looks like there isn't much oil business going on in that area! You sure it's not coolant? Coolant would defiantly leak with the car off since it still holds pressure for such a period of time

NHerron said:

This is a pic I saved from Bogus on here and it looks like there isn't much oil business going on in that area!

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That's exactly my point.. . It doesn't look like an oil leak prone spot as there is no oil there besides in the head itself. I'm pretty sure it's not coolant. And it's not coming from the allen key plug.

But if it was the headgasket leaking, wouldn't it show in the compression or leakdown numbers?

BTW, from the information i have in my journal, 13% leakdown for a brand new engine (never run) is actually not bad at all. Someone correct me if i'm wrong, please.

No I don't think that's bad at all (7-8% especially after only 24 miles) my build has forged pistons with .021"/.024" ring end gaps and I get 6% leakage warm after 500 miles

Did you get the head squared up what gasket setup are you running, looks like solid copper?

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

^^I'm forged too and my end gaps are even looser than that..

The head and block were decked and i presonally checked them several times. The headgasket is an Mitsu-MLS that i'm re-using. I did get it soaked in copper spray though. Other than that it has l19's at 105 ft/lbs

YZFR1 said:

That's exactly my point.. . It doesn't look like an oil leak prone spot as there is no oil there besides in the head itself. I'm pretty sure it's not coolant. And it's not coming from the allen key plug.

But if it was the headgasket leaking, wouldn't it show in the compression or leakdown numbers?

BTW, from the information i have in my journal, 13% leakdown for a brand new engine (never run) is actually not bad at all. Someone correct me if i'm wrong, please.

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There is nothing over in the deck area to leak oil. It would leak coolant from that side, but not oil. The closest thing to leak oil is the oil drain in the middle,, but there is no pressure to force the oil out so that isn't it. It is either coolant, or oil from the cam seal.

Just went back in there and double checked everything. It is definetly not coolant, plus i mostly have water in it right now so it would've already dried over night.

Looked everywhere around the cam seals and don't see any obvious leaks. Turned the cam gears around to get better visibility and don't see any streaks of oil or anything.

I might try to remove the timing cover some time in the near future to get better visibility but other than that i'm bumed about this. Just doesn't make sence

The engine checks out and it's not leaking that bad at all, it just sucks getting new engine coated in oil. I was really hoping to keep it dry

Power steering?

If it is a small leak, It could be your valve seal that is leaking and getting out by the exhaust gasket not sealing well.
I had a leak on the opposite side of head (4th runner), and it was my valve seals leaking and getting oil into the runner and getting out from the gasket, It was a mess, It was easy to track though, which it barns to much oil and had all the effects of valve seals.

Pretty sure it's not power steering as it is way above it

I've thought about the valve seals too and now that i think about it the exhaust manifold did have some oil right on the rim of that runner. However, if that is it, wouldn't both runners in the head and manifold be more wet? The turbo looks dry and so does the exhaust collector

The heat in the runners is extremely hot that will burn the oil very well and not saying that your leak is very little compared to mine.
I didn't even noticed that It was running oil by looking in the runners, first I thought It was the bolt that was leaking oil, I removed it and put sealer in it, But noticed a little wet at the valve (inside the head runner), and changed the seals.

Check the valves to see if they are wet (inside the head runner), I don't think you will see a sign of wet which yours is just a tiny leak.

If it's not shiny, check the amount of buildup on #1 valves vs all the other sets of valves

Update:
There is definetly some oil on the exhaust manifold and both the head and exhaust manifold rims, however, insdide the runners all looks good. No signs of oil and all valves are still shiny.

Just to be sure, i called the shop that did the head for me. It is supposed to be a good shop and they looked up my profile and said that all valve stem seals were replaced. So they are new!

This just keeps on getting more and more interesting!!

Is it possible that could somehow be oil from blow by??.. she is a loosey goosey

I'm using a rather factory pcv system with an in-line see through filter, is it possible my crankcase pressures are high enough to cause this?

YZFR1 said:

Update:
There is definetly some oil on the exhaust manifold and both the head and exhaust manifold rims, however, insdide the runners all looks good. No signs of oil and all valves are still shiny.

Just to be sure, i called the shop that did the head for me. It is supposed to be a good shop and they looked up my profile and said that all valve stem seals were replaced. So they are new!

This just keeps on getting more and more interesting!!

Is it possible that could somehow be oil from blow by??.. she is a loosey goosey

I'm using a rather factory pcv system with an in-line see through filter, is it possible my crankcase pressures are high enough to cause this?

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It would have to be coming from the exhaust port which you said was dry.

Bumping an old thread because my oil leak looks identical. I've been tracking oil leaks for the better part of 10 years. I just replaced the cam seals, took the car for a drive, and still a leak has popped up on the front of the block, closest to the timing side. I just did a timing job and checked around, under the timing cover looks great. Blue gates belt is dry, clear upper timing cover is dry. Block is wet under the #1 Runner.

Very stumped, any ideas would be amazing.

bettfootball said:

Bumping an old thread because my oil leak looks identical. I've been tracking oil leaks for the better part of 10 years. I just replaced the cam seals, took the car for a drive, and still a leak has popped up on the front of the block, closest to the timing side. I just did a timing job and checked around, under the timing cover looks great. Blue gates belt is dry, clear upper timing cover is dry. Block is wet under the #1 Runner.

Very stumped, any ideas would be amazing.

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Im having the exact same issue right now. What did it end up being??

Cesar Corona said:

Im having the exact same issue right now. What did it end up being??

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No idea, just had the head completely machined and built, and am doing the same to the block.

This oil leak sometimes happens.
Assuming there is totally no leak from the camshaft seals, valve cover gasket, exhaust valve seals etc etc, In my experiences, if you still see oil leak under the exhaust #1, the leak is actually occurring at the intake/driver side's oil return port (where the green circle) and the oil goes along the edge of the head gasket and goes to the front side because of the engine angle, like the green line in the pic below.
This mostly happens when it requires to re-torque the head bolts/studs, especially if you have a MLS or a Copper head gasket.
If re-torquing wouldn't fix the issue, it probably needs to resurface the head/block or replace the head bolts somehow if you are using old stock head bolts.
I had this leak a couple of times. In my cases, the leak was gone after I re-torqued.

Leaky valve covers gaskets do this crap all the time.