I just thought I'd pass along this little tip that may benefit someone who is looking for a hard to find oil leak.
I had a small oil leak in the area around the rear of the oil pan on my new 540. At first glance, it appeared to be a rear pan seal leak which would have been expected due to the mods I had to do to the pan after it was found to be defective.
After I pulled the trans and flexplate, it appeared that it was NOT coming from the rear pan seal or the rear main seal.
So here's what I did.
I have standard push-in breathers in both GMPP valve covers. I removed them and replaced the rubber grommets with a pair of the solid grommets (the kind you cut the opening yourself) you can buy at most auto parts houses. This blocked off the breather holes. Then, I had a friend apply air to the crankcase thru the dipstick tube using a rubber-tipped blow gun. You want to apply air VERY carefully because you CAN blow out other gaskets if you apply too much.
Then, I laid under the car with a spray bottle filled with water and a little dishwashing liquid, and sprayed the pan area while my friend applied the air. Sure enough, as soon as a little air was applied, the bubbles started. The leak was at the last pan stud on the pass. side BETWEEN the pan and the little reinforcement plate that stiffens the last two bolt holes of the pan.
I repaired the leaking area with "Right Stuff" and let it set up for a day. We re-tested it and the leak's gone.
This method will work for ANY oil leak and it is also a good way to check a new or used assembled engine while it's on the stand before you put it in the car. This will also work for finding leaks around the intake manifold corners or at the front/rear intake to block seal area.
Hope this helps someone.
Randy
I had a small oil leak in the area around the rear of the oil pan on my new 540. At first glance, it appeared to be a rear pan seal leak which would have been expected due to the mods I had to do to the pan after it was found to be defective.
After I pulled the trans and flexplate, it appeared that it was NOT coming from the rear pan seal or the rear main seal.
So here's what I did.
I have standard push-in breathers in both GMPP valve covers. I removed them and replaced the rubber grommets with a pair of the solid grommets (the kind you cut the opening yourself) you can buy at most auto parts houses. This blocked off the breather holes. Then, I had a friend apply air to the crankcase thru the dipstick tube using a rubber-tipped blow gun. You want to apply air VERY carefully because you CAN blow out other gaskets if you apply too much.
Then, I laid under the car with a spray bottle filled with water and a little dishwashing liquid, and sprayed the pan area while my friend applied the air. Sure enough, as soon as a little air was applied, the bubbles started. The leak was at the last pan stud on the pass. side BETWEEN the pan and the little reinforcement plate that stiffens the last two bolt holes of the pan.
I repaired the leaking area with "Right Stuff" and let it set up for a day. We re-tested it and the leak's gone.
This method will work for ANY oil leak and it is also a good way to check a new or used assembled engine while it's on the stand before you put it in the car. This will also work for finding leaks around the intake manifold corners or at the front/rear intake to block seal area.
Hope this helps someone.
Randy
