Engine Oil Drain Plug Leak

[The Critic]

When my dad used to change the oil on the Saturn, he used a soft fiber/cork gasket on top of the rubber o-ring whenever he changed the oil. He replaced that homemade fiber/cork gasket at each oil change and it worked just fine until recently. Suddenly, I began to see some slight seepage from the plug area. Not enough to land on the floor, but just enough to get the oil pan area wet.

Now, I took over the oil changes. At the last oil change, I installed a new o-ring from NAPA on the drain plug. I did not use any homemade gasket. I tightened the plug. On Sunday, I was at the shop and the technician and I both noticed that the drain plug area is wet. Again, just wet, no drip on the floor.

What's the cure? Also, if this helps, the oil drain pan has a "groove" that is outlined by someone overtightening the drain plug at one point. However, I've had the groove for a very long time and the oil leak issue did not appear until recently.

Thanks.

 

[paulo57509]

I don't have a cure, but I had an experience similar to yours. Eventually, the pan threads stripped. When I examined the drain plug threads, they looked like buttress threads instead of a "V".

My theory, based on the mileage on the engine and 3k-5k OCI's is that the threads could only handle so many loosen/tighten cycles. This engine has had close to 100 oil changes in it's life.

I just teflon tapped a Fram Sure Drain in place of the plug and it's been fine. I do have a new pan that's been sitting on the shelf for the past three years, but I haven't had the ambition to install it.

BTW, myself and the previous owner used a torque wrench on the plug.

 

[ZZman]

I had the same problem on my convertible but it would drip a little. I put a small amount of Permatex around the bolt head and tightened it down. No Leaks now.

 

[pcoxe]

My 84 Camaro had a plastic/nylon washer under the head of the oil pan drain plug that cracked and caused a leak. I replaced it with a soft copper washer that sealed but wouldn't break. I also put a strip of teflon tape on the threads just ahead of the bolt head for extra insurance.

 

[mechtech2]

The cork/felt would impede the function of the designed sealing.
So lose the additional stuff.
Make sure the seal or gasket is OK, at this point.
A little non hardening Permatex is a good fix if your can't get it to work with good hardware alone.

 

[doitmyself]

Is that a steel oil pan and is there any possibility it has developed a pin hole leak due to corrosion? Some vehicles have a history of this (my work place F-250), but we live in the rust belt.

Maybe clean it off very good, then check it every few hours to determine the actual leak area.

Or, maybe it's just a quirky thing and a new OEM plug with o ring might cure it. How about a slightly oversize o-ring?

Finally, maybe ditch the OEM style pan bolt and go to one designed with a gasket/washer.

FYI, I once did an oil change on a friends Taurus and was shocked to find a "toggle bolt" like drain plug installed. Some iffy lube place must have installed it after losing/wrecking the original because the threads were pristine. I bought a correct replacement and installed it. But, discovering and removing that toggle assembly was a strange experience.

Good luck.