Oil leak - drain plug
Thread Starter
Joined: Oct 2008
Posts: 10
From: Michigan
Oil leak - drain plug
I'm new here and this is my first thread.
I have a 1967 Mustang and after an oil change I just noticed there is an oil leak coming from the drain plug. I thought it was the plug so I replaced that. However, even with the new one the leak continues. So I was wondering if it's going to require a new oil pan - the one there is probably old as came with the car when I bought it couple of years ago. Does anybody have any thought?
I have a 1967 Mustang and after an oil change I just noticed there is an oil leak coming from the drain plug. I thought it was the plug so I replaced that. However, even with the new one the leak continues. So I was wondering if it's going to require a new oil pan - the one there is probably old as came with the car when I bought it couple of years ago. Does anybody have any thought?
6th Gear Member
Joined: Oct 2006
Posts: 6,417
From: Cork, Ireland
there should be a copper ring as washer under the plug. not having one might cause it. Maybe the threads are a bit worn, so new plug or a good load of blue loctite might help
in any case you'll have to drain the oil again (unfortunately) and inspect. At least you can tell where it's coming from that's the battle nearly won already ;-)
welcome to the forums
in any case you'll have to drain the oil again (unfortunately) and inspect. At least you can tell where it's coming from that's the battle nearly won already ;-)
welcome to the forums
4th Gear Member
Joined: Mar 2007
Posts: 1,080
From: Chandler, Az
Or a nylon gasket on the drain plug. Also, sometimes it runs down from the front seal down to the bottom. Either way, oil will run to the lowest point, wipe the oil off the pan and see if you can find the leak.
Thread Starter
Joined: Oct 2008
Posts: 10
From: Michigan
Thanks guys. I have identified that the leak is coming from the drain plug - I cleaned the oil pan to see that. The plug has the nylon gasket (I also tried the rubber one) but the leak is still there. The problem is that I was not able to tighten the plug very hard (it just goes with no end) so that's why I suspect there is something wrong with the pan and as the old oil was dense (or dirty) I didn't see the leak before.
4th Gear Member
Joined: Jan 2007
Posts: 1,282
From: TX
wlandin,
When I first bought my 67 (now gone), the first thing I did was change the oil. Figured twenty minutes, right? Nope. I had the same problem as you. The plug would just turn and turn.
On my inline 6's pan, there was a one inch by 3/4 piece of metal riveted to the inside of the pan with a single rivet. It is just under an 1/8th inch thick with a hole in the middle and threads in the hole. Basically, it was what the plug threaded into. At some point, any one of my previous owners had pushed a plug in and had bent the threaded metal thingy back away from the "skin" of the pan. No plug could grip etc. My pan looked like s$%t after 40 years of abuse, so I just bought a new one. (Pain in the *** to swap it out, so much for 20 minutes for a simple oil change when I brought her home.
).
In hindsight, I wonder if I couldnt have just rigged something to pull the threaded metal thingy back down to its original position. The problem was that it had just that single rivet to counter the force of pushing the plug in as you start to thread it.
Long winded explanation there, sorry! Some things are just hard to describe.
When I first bought my 67 (now gone), the first thing I did was change the oil. Figured twenty minutes, right? Nope. I had the same problem as you. The plug would just turn and turn.
On my inline 6's pan, there was a one inch by 3/4 piece of metal riveted to the inside of the pan with a single rivet. It is just under an 1/8th inch thick with a hole in the middle and threads in the hole. Basically, it was what the plug threaded into. At some point, any one of my previous owners had pushed a plug in and had bent the threaded metal thingy back away from the "skin" of the pan. No plug could grip etc. My pan looked like s$%t after 40 years of abuse, so I just bought a new one. (Pain in the *** to swap it out, so much for 20 minutes for a simple oil change when I brought her home.
).In hindsight, I wonder if I couldnt have just rigged something to pull the threaded metal thingy back down to its original position. The problem was that it had just that single rivet to counter the force of pushing the plug in as you start to thread it.
Long winded explanation there, sorry! Some things are just hard to describe.
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
3rd Gear Member
Joined: Mar 2008
Posts: 585
From: Baltimore MD
I cross threaded the drain plug on my 68 years ago. I went to the auto parts store and picked up a rubber plug that came with a special install tool. You shoved the tool into the rubber plug making it thinner. Then you stuck it in the hole, twisted it once it was seated and it sealed itself. Bad explanation but it worked great until I ruined the car trying to replace the engine because I was young and dumb and had no clue how much I didn't know.
3rd Gear Member
Joined: Oct 2007
Posts: 584
From: Illinois
As for the drain plug, use the oversize plug from the auto parts store and it will work. If you ever have the oil pan off you may want to consider what I have done in the past and am getting ready to do on my mustang engine. On the cars I have owned and rebuilt the engine or had the oil pan off, I have drilled out the stock drain plug hole then taken a short 1/2" or 5/8" bolt and nut and welded the nut to the oil pan. The bolt is now the drain plug and is almost impossible to cross thread because the threads are much longer than the stock ones. When I have done it I have turned the mating faces of the nut and bolt on my lathe so that they are perfectly flat, but I doubt that is necessary. A nylon or rubber washer when installing finishes the job. I have never had one of my oil pans with this mod leak. Incidentally, the copper washers are great, but they work harden and after a while you should either replace them or anneal them.
