2uz v8 oil leak source? (1 Viewer)

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Well did a timing belt service this weekend. Truck has 150k and looks to be the original. Belt was in pretty good shape from what i could tell and everything else looked good. Go toyota!

Today i went in there again just to inspect for any leaks etc before a long road trip. Found the drivers side under the head on the front side to be covered pretty good with oil. Brake cleaned the area and let it run trying to determine the source but its a rats nest in there of hoses and suspension, couldnt tell.
Is there a common oil leak source in this area?
A couple pics that may or may not help.
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no not common. Could it be coming from the oil filter?
 
Valve cover gaskets?
 
Pull the drivers timing cover and check the cam seal. It could be leaking and dripping down the front cover.
 
2UZs just generally don't leak. Did you do cam seals or remove the valve covers for any other reason? Leaking down onto the a/c compressor would put that on the driver's side, and there really isn't a good oil leak source over there other than the valve covers.

Let us know.....
 
It is also very possible that the valvle covers are loose. I had it happen. The bolts back out and it can leak.

Tighten them down and see if it stops.
 
I did not do cam seal. Vvti motor and didnt want to get into that. Pulled the drivers cover off best i could without completely yanking it out and with an inspection mirror doesnt seem to be the cam seal.
One thing to mention. When i was getting the tbelt on i had to back the drivers cam up a hair and the bolt on the end loosened. It surprised me as the force to undo was so slight. Once i had the belt on i tightened it up.
EDIT: Loosened the screw plug seen here:
http://4runnerclub.com/i/4r_files/f...toyrm/07toypdf/07rmsour/4runnerr/00800510.pdf
Seems only purpose is to seal the main camshaft bolt.

Looked under valve cover as well and dry. Guess ill keep looking.
 
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Pretty dry inside the cover. And no drippage on the bottom side from what i can tell with mirror.
 
Ok will do and keep this thread updated. Thanks guys.
 
Sorry to bump an old thread but I have the exact same leak leaking onto my ac compressor and making my mess of my various hoses in the area. What ended up being your issue? I too am speculating that it is the valve cover gasket which I have yet to replace. I've only tried tightening it up a bit.
 
It was the cam seal and it's a lot of work to replace ie pull cams. I used some HM syn oil on a couple short oil changes and it stopped. Good luck.
 
It was the cam seal and it's a lot of work to replace ie pull cams. I used some HM syn oil on a couple short oil changes and it stopped. Good luck.
Thanks for the follow-up. I'll see about throwing in some kind of additive then that takes the place of high mileage oil. I just did a fresh oil change with normal synthetic oil.
 
Thanks for the follow-up. I'll see about throwing in some kind of additive then that takes the place of high mileage oil. I just did a fresh oil change with normal synthetic oil.
Don’t don’t do that. If it’s not leaking enough that you don’t have to add oil, high mileage seal swellers will do more harm than good.
 
Noted. I guess I will play the wait and see approach. In the meantime, I did buy brand new valve cover gaskets and spark plug tube seals from the local Toyota dealership and I was planning to replace those as the first line of defense.
 
Don’t don’t do that. If it’s not leaking enough that you don’t have to add oil, high mileage seal swellers will do more harm than good.

I have never heard of this effect.
 
I have never heard of this effect.
It’s not so much that they in and of themselves cause issues. The issues occur when you go back to normal oil that doesn’t have the same level of seal modifiers in it. The seals may shrink back to normal size and cause further or increased leakage.
 

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