What type of leak is this?

Rich

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The area circled in yellow is what I'm asking about. It's only on the driver side. It's not wet and looks oil based, but I'm not sure. Anyone have a clue?
Mustang Head.JPG
 

Rich

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Is that a possible head gasket leak? Car is stock with 31k miles. It's not wet in the valley or on the passenger side. Just that small area.
 

DieHarder

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Wouldn't call that a leak. I'd call it a weep.

I'd just clean it and monitor it now that you know it's there. If it gets worse then worry about it.
 

Rich

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Well, something caused it so I'd like to figure out what that is. Possibly a loose or slightly loose head bolt?
 

skwerl

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You could pull the valve cover and retorque the heads. Don't over torque them, just make sure they are tight enough.
 

Rich

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You could pull the valve cover and retorque the heads. Don't over torque them, just make sure they are tight enough.
Aren't those bolts torque to yield one time use only?
 

Juice

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I would not even call that a weep.
Nothing stays looking new.
Clean it off and monitor it.
If you are not losing oil or coolant or having overheating issue, dont look for issues that are non-issues.

Ps:looks like a very minor oil stain from the timig chain area.
 
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Rich

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Yes. What's your point?
The point is torque to yield bolts cannot be loosened or tightened any further otherwise they risk being ruined. You either loosen it all the way and use a new one or leave it as is. Is that not the correct procedure?
 

DieHarder

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I would not even call that a weep.
Nothing stays looking new.
Clean it off and monitor it.
If you are not losing oil or coolant or having overheating issue, dont look for issues that are non-issues.

Ps:looks like a very minor oil stain from the timig chain area.

This....took from new to until now to get just that little bit of staining. Many of us would love to have an engine that clean. Nothing to worry about...these are not the droids you're looking for...move along.
 

Rich

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I'm not worried about the stain fellas, I just want to know what caused it because I'm curious. I thought it might be oil or coolant, but I wasn't sure. It just seems odd that an 31k mile engine would have a leak of that type in that area. Couple that with the fact that it is not wet which means that it isn't continously leaking is what threw me for a loop. I appreciate the replies though.
 

skwerl

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The point is torque to yield bolts cannot be loosened or tightened any further otherwise they risk being ruined. You either loosen it all the way and use a new one or leave it as is. Is that not the correct procedure?
I was thinking about this some more this afternoon and you are correct. I forgot that the bolts are not just torqued to a set number, but to a set number and then an additional 1/4 turn or 1/2 turn or whatever.
 

Rich

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I was thinking about this some more this afternoon and you are correct. I forgot that the bolts are not just torqued to a set number, but to a set number and then an additional 1/4 turn or 1/2 turn or whatever.

I've never done anything with the heads, but I remembered reading a while back that torque to yield bolts are one-time use and cannot be changed once they are set. I appreciate you confirming that though.

I cleaned the area (wasn't much to clean since it was dry) and I'll just check it out a couple times a month to see if it worsens, thanks!
 

Laga

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When you cleaned the area, did the water bead up on the strain, or mix with it? If it beaded up, it’s oil based. Mixing would be coolant.
 

Dino Dino Bambino

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I wouldn't call it a leak; more like a bit of oil "sweat" from the driver's side head gasket. I wouldn't be concerned about it. Just monitor it from time to time and see if it gets worse.
It's definitely oil. There's no coolant in the valley of the block where it would normally accumulate if it leaks from a heater hose, and the coolant passages in the head are further in closest to the combustion chambers.
Since the driver's side is where the PCV hose is situated, check it for any blockage and also apply vacuum to the PCV port in the valve cover to ensure that it draws crankcase gases.
 

07 Boss

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I'm not worried about the stain fellas, I just want to know what caused it because I'm curious. I thought it might be oil or coolant, but I wasn't sure. It just seems odd that an 31k mile engine would have a leak of that type in that area. Couple that with the fact that it is not wet which means that it isn't continously leaking is what threw me for a loop. I appreciate the replies though.


31K miles but its 10-15 years old. Engines, transmissions, rear ends, pumps... all weep power, as I call it, over time. Seals and gaskets dry up and get worn.
 

Rich

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When you cleaned the area, did the water bead up on the strain, or mix with it? If it beaded up, it’s oil based. Mixing would be coolant.
It didn't do anything since it was so dry. All I did when trying to clean it was wipe away a small amount of dirt so to speak. Whatever has leaked has "soaked" into the head and only the stain remains.

I wouldn't call it a leak; more like a bit of oil "sweat" from the driver's side head gasket. I wouldn't be concerned about it. Just monitor it from time to time and see if it gets worse.
It's definitely oil. There's no coolant in the valley of the block where it would normally accumulate if it leaks from a heater hose, and the coolant passages in the head are further in closest to the combustion chambers.
Since the driver's side is where the PCV hose is situated, check it for any blockage and also apply vacuum to the PCV port in the valve cover to ensure that it draws crankcase gases.
The PCV does draw a vacuum, however, I do have a catch can between the exit port and intake. Would that cause enough pressure to build up and push some oil between the head gasket? I didn't think it would, but I could be mistaken.

31K miles but its 10-15 years old. Engines, transmissions, rear ends, pumps... all weep power, as I call it, over time. Seals and gaskets dry up and get worn.
You are correct. After some thought, I came to the same conclusion. Time wears out everything regardless of use :(
 

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