I had the oil cooler fail on my '03 Cobra. You would be suprised how much 5W-20 oil can flow out of that tiny "pinhole". My oil cooler had failed internally. The lug was tight.

 

well i tightend the lug and it slowed way down to a seep. so im guessing i washed the seal.
Does anybody know if that seal is replaceable?

 

I own a 97 mustang v6 but it sounds like I have this same problem. I don't much about the car from the mechanic side but it sounds the same.

I brought it to a friend of mine who works at an oil change place and he saw the leak - only while the car was running - coming from the area where the bolt goes to it. He tightened it but it still leaks.

I'm thinking its the same problem and if it is could you please tell me what you did to fix the problem. Thanks a ton guys, I hope its the same part we are talking about here.

 

Not sure if the v6 has this cooler but if it does here is what i did to stop my leak. I took off the oil filter and used a 1/2 inch allen wrench to tighten the center bolt, put the oil filter back on and it still leaked. so took the filter back off and tightened again, i did this three time ( i was worried about stripping out the threads so i didnt put alot preasure on the bolt ) after the 3rd time it still had a very slow drip and i thought i was going to get a new cooler but it must of been residual cuz it didnt leak the next day, and its been a few months with no probs

 

what a relief just tightend bolt and changed oil no leaks. i talked to ford today and the part is up 409$. once again thanks alot

 

W up Great Friends ... so ... I got the pinhole OIL leak ... very slow leak ... then I did get the 1/2 inch allen ranch and got the oil screw thing tight ... as I did it COOLANT started leaking on a steady base ... green coolant and plain ? I did drain the engine oil and it is not mixed w coolant and vice-versa ... , its leaking coolant from the seal itself now under/on to the oil filter housing ... Does anyone have a suggestion ... easy to do it yourself or what ? How bad is this ... peace out .. thanks

 

.... on the pinhole leak ... got the oil filter screw tight w the 1/2 inch Ellen and as I did it the oil leak stopped but the coolant , pure coolant is now leaking ... weird ... ,oil and coolant are not mixed .... did drain the oil its not mixed w coolant ... any suggestions please ... thanks

 

First off what was the logic Ford used to intentionally put the pinhole on the outside of the housing anyways? Did it have anything to do with the possibility of a water leak, or a mixing of the fluids? It almost seems similar to a weep hole on a water pump. Nevertheless after careful examination of the part off the vehicle, it appears there is a factory applied epoxy substance around a diamond shaped part that the filter lug passes through. While I concede that over tightening the lug has apparently stemmed the oil leak, (for a limited time) I think the epoxy is what has failed and is allowing oil under pressure when the vehicle is at operating temperature to seep between the diamond shaped part that I believe is factory pressed or otherwise assembled into the core of the unit and eventually out the pin hole.
I am going to over tighten the lug as another suggested, however I am also going to enlarge the hole just enough to thread it to an 8/32, or 10/32 hole, being careful not to rupture the cartridge within and put a screw with a copper washer on it in the hole, and see what effect that has. I am confident the leak is greater than residual and the cavity from which it is seeping is ultimately under pressure....which brings me back to the original question; why is the hole there in the first place?

 

Ok...I suppose I came to the party late, but I have it figured out. The oil cooler "will" come apart further than just removing it from the engine. I was extra careful and pried the cartridge from the remainder of the housing and low-and-behold there are 3 more "o" rings sealing the oil from the water circulating through the oil cooler. The "bottom" "o" ring is-the-one whereby if it leaks will allow the oil to leak through the pinhole. (Over) tightening the oil filter lug with the allen wrench is a stop-gap measure since you are essentially trying to stop the leak by applying more pressure to an otherwise flat/worn out "o" ring seal. If the pinhole is sealed, eventually the oil pressure will build and force its way through the next seal and into the cooling system. The good news is that most companies that deal in hydraulic cylinders or lines (Pirtek) have, or can get the necessary "o" rings to repair this issue. I was lucky enough to have a refuse truck repair center next door that had the "o" rings. The "quality" repair was successful and the customer is very happy. Parts and labor.....roughly $200......retail.

 

I have a 99 cobra with a leak that appears to run down the back side of the cooler and run off the bottom near the middle. Where is this pinhole that could be the culprit?