What to do about a stripped oil drain plug?

nelstomlinson

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I changed the oil in my new-to-me '94 today, and found that the drain plug had some kind of rubber washer. I got the plug back in, but it doesn't feel right and I think the hole in the pan may be stripped out. I'm not ready to pull the engine to replace or repair the pan; I need to run this truck all summer, starting now!

Is there a kit to repair the threads in the oil pan that works, that can be used underneath the truck?
 

genscripter

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You could try a tap and die set. See if you can reform the existing threads back to their previous threading, but judging by your description, that's not in the cards. Find a size that is just bigger than the previous, drill it out, and thread it. Then find a bolt that matches the threads. You will get some minor metal shavings near where you are threading, but most should fall out. To make sure none stay in the oil pan, you can pour down some oil with the drain plug open, and that might flush down any residual shavings from the tapping of the hole. Also, you could put a magnet in there to catch any shavings as well.
 

nelstomlinson

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You could try a tap and die set. See if you can reform the existing threads back to their previous threading, but judging by your description, that's not in the cards. Find a size that is just bigger than the previous, drill it out, and thread it. Then find a bolt that matches the threads. You will get some minor metal shavings near where you are threading, but most should fall out. To make sure none stay in the oil pan, you can pour down some oil with the drain plug open, and that might flush down any residual shavings from the tapping of the hole. Also, you could put a magnet in there to catch any shavings as well.

That should work, and it may be the best I can do. I was sort of hoping for something like a nutsert, but expecting one of those to seal probably isn't realistic.

I wonder if I could clean it up and JBWeld on a nut? Anyone ever try that?
 

DrCharles

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You have more confidence in JB Weld with hot oil immersion and diesel engine vibrations than I do... Don't try it. Drill and tap, as suggested.

Or you could weld or braze a nut on the outside, but you'd have to pressurize the engine to a couple psi with an inert gas so the oil vapors don't go boom.
 

nelstomlinson

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You have more confidence in JB Weld with hot oil immersion and diesel engine vibrations than I do... Don't try it.

Yeah, you're probably right.

They sell oversized self tapping oil drain plugs at the car parts store.

That is good to know! I've always been really careful not to screw up my drain plugs, so I've never had this problem before.
 

pelky350

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They sell oversized self tapping oil drain plugs at the car parts store.
Idk if idi pans are stronger than a 5.0 truck pan but when this happened to my bronco the spot welded on tab broke off trying the oversized tapping plug and I had to remove my pan.. but maybe It was my bad luck. It didn't take much for it to pop off either, I think it was damaged previous to me also.
 

franklin2

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Idk if idi pans are stronger than a 5.0 truck pan but when this happened to my bronco the spot welded on tab broke off trying the oversized tapping plug and I had to remove my pan.. but maybe It was my bad luck. It didn't take much for it to pop off either, I think it was damaged previous to me also.

Just like using a tap, when using the "self tapping" repair drain plug, put grease on the repair plug threads to catch the metal shavings, and get it started, and then back it up, then go a little farther, and then back it up, and slowly work your way in. If the threads get clogged with metal, clean them off and then keep slowly going in.
 

79jasper

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Idk if idi pans are stronger than a 5.0 truck pan but when this happened to my bronco the spot welded on tab broke off trying the oversized tapping plug and I had to remove my pan.. but maybe It was my bad luck. It didn't take much for it to pop off either, I think it was damaged previous to me also.
It's not much different. Won't have enough meat left for drilling and tapping to the next size. Not to mention you'll be ramming into the pickup tube....
I would do the option of a nut/NPT fitting.
Some have gotten a fumoto valve and jbwelded that in.

Sent from my SM-G892A using Tapatalk
 

hesutton

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Not to mention you'll be ramming into the pickup tube....
Yup....

The oil pick up sits right over the oil drain. It is so close, if you dent the pan there (like sitting the engine down on the pan...) it will make draining the oil a long slow painful process. Ask me how I know....:angel:


Doubt you'll have room to run a tap in deep enough to cut the threads properly.

Without pulling the pan... I like the nut with NPT idea.

Heath
 

nelstomlinson

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Thankfully, I was able to clean up the threads and all is well. I appreciate the ideas you all came up with, and I'm going to try to have a backup plan lined up for just in case one of my old trucks turns out to have a drain plug that really is stripped.

After this scare, I will be brazing a nut onto the oil pan of each engine I tear down.
 

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