Oil leak in new motor


Jun 25, 2005
Venice FL
I rebuilt a new 302 for my 88 GT. I have approx 50 miles on the motor and it has a nasty oil leak. I think this is the problem. The plug in the picture top of the block is not on my new block. I know it was there before install but there seems to be an open hole there now. What would cause this??


Oil pressure is 60 psi and comes down to approx 50 when hot at idle. How much oil would come out of this plug?? I dont mind the extra work but dont want a reoccuring problem. Thanks


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Thats just my problem the motor is running and cant seem to locate the oil leak. I climbed up into the enigine bay with a flashlight and this is the only thing I can come up with. I am going to pull the upper intake off and look a little closer. I just dont get it. After I remove the intake and reinstall I am going to try the dye with a black light and see what turns up.
Ok, pulled the intake off and sure enough a visible hole where a plug should be. Now the plug that I can see has threads. Which is odd. My original block is just like a normal freeze plug. I pulled the motor that I rebuilt out of a Mark VII. It only had 60,000 miles and the coolant was fresh and green. It was the best block I have taken apart. The big question is what size and pitch are those threads for this oil galley?? The reason I ask is because instead of removing the lower intake, I would like to insert the proper size bolt with sealant to stop the leak.
Additional thought came to mind is how would I have good oil pressure for a 30 mile ride if the oil galley plug is not there?? The threads seem to be metric maybe M12. A 7/16 bolt fits sloppy and a 1/2 doesnt fit. The saga contuines.
Help?? I have the car back together and the nagging question is if the oil galley plug is gone how do I have 50 psi oil pressure around town?? I have my doubts on the cause for the oil only to leak after the car is off and parked. I have thoughts of either vavle cover gasket or leak behind the lower rear intake to block surface. I am in the process of testing it out in a little while and we shall see.
Not the oil galley plug for sure. Concensus is in and I can see an oil puddle on the passenger side just at the rear of the head. The lower intake must not be sealing to the block. I used a thick bead across the back with RTV red. Oh well I have once again been :owned: by this car. After Bradenton NMRA I will rip it back open once again.