Oil Pan Gasket Replacement

by
Tony Robinson, tonyr@dzn.com

Some of the most common problems with a leaky oil pan gasket stem from not using sufficient care when re-attaching the pan and replacing the gasket. When an oil pan is overtightened, it causes the holes to bend upward toward the block. A gasket will seldom fill in the “new” gaps so it leaks.

Sealants will work and fill in these new spaces, but we are all guilty of being in too much of a hurry so we don’t allow them to cure properly and when you put oil or any kind of pressure behind it, it blows out the sealants ability to seal.

Two gaskets of the “rubberized” material variety may help by providing the cushion necessary to fill the uneven surface created by overtightening.

I have used everything from a 1×4 board to a 500 lb. anvil to straighten out oil pan holes. If you use a 1×4, place the even sawed, smooth end under the lip (outside bottom) of the pan and with a hammer, lightly tap the area of each oil pan hole until it is visibly even with the rest of the sealing surface of the pan.

Spread a thin bead of sealant on the sealing surface of the pan, and apply the gasket, pressing down all the way around the pan and sort of wiggling the gasket a bit to spread the sealant. Turn the pan over and place it on a smooth even surface and press down in the center of the pan lightly and let it SIT OVERNIGHT.

When you are ready to put the pan back on, clean each bolt hole in the bottom of the block with a good parts cleaner such as carburetor cleaner. Run a bead of sealant on top of yesterdays gasket and smear it as evenly as possible. Hold the pan close enough to the block to get the bolts started without actually touching the pan to the block until you have several bolts in to hold the pan up. Apply some sealant to the bolts before you thread them in. (This is why you cleaned the holes in the block)

Once all the bolts are in place finger tight, snug them down in a criss- cross fashion until they are all just snug. When they are all snug, go back and torque them in the same criss-cross fashion to I would guess 7-10 ft.lbs. No more or you’ll bend the holes out of shape again.

Now, let it sit overnight again to let the sealant cure. Hopefully, we have stopped your leaky pan.

I have found that LBCs are not too expensive to maintain, they just take a lot of TLC.

Tony Robinson, tonyr@dzn.com