W.E.G.

I'm dealing with a leaking drain plug.

This was a Jiffy Lube incident. Yes, I let them change my oil. Go ahead and kick me in the nuts, and get it over with.

Yes, I took the car home, and the next day I had a puddle of oil in the driveway. Much larger puddle (and different location) than the long-standing slow leak from the rear main seal. The RMS leak is a discussion for a different day.

The drain plug was so stripped, that I could nearly turn it with my fingers. Very light clockwise pressure with a wrench, and it just turns and turns. A fairly steady drip,... drip,... drip... from around the plug was clearly visible.

I don't know yet whether the stripped part is the plug, or the pan. I'm assuming the worst, that being the pan.

I have the fancy-schmantzy TIME-SERT thread repair kit (which I've never used) for a 1/2 x 20 hole.
This thing:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

The online vendors are listing the correct drain plug for my 2.8 V6 as being something OTHER than a half-inch plug, that being a metric size: Thread Size: M12-1.75
http://www.oreillyauto.com/site/c/de...2330&ppt=C0332

So, the metric conversion for 12mm is just short of being a half inch. The converter says 12mm = 15/32"

I already have a new half-inch drain plug: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Yes, I ordered the tool and the plug, thinking it was half-inch size, and now it appears that the plug is actually a metric size.

It will be just my luck that now I have a fancy purpose-built bunghole repair tool, the problem will turn out to be just the plug, and the threads in the pan will be completely unmolested. A lifetime's series of this sort of thing makes me not optimistic that it will turn out to be the drain plug, and ONLY the drain plug.

Assuming that the threads on the drain pan are in need of repair (I won't know until I can get properly under the car two days from now), will the Camaro gods strike me blind if I just go ahead and drill-out the threads on the drain hole to take the 1/2" TIME-SERT threaded insert, and just use the new 1/2" drain plug?

I know that once I start drilling-out the exisiting threads on the oil pan, I'm in this for more than a dime.

Should I just hit myself in the head with a hammer now, and suck up the idea that I should simply use the expandable rubber-stopper repair instead of trying to get fancy? I could buy more than a bushel of expandable rubber plugs for what it will cost if I end up having to replace the pan. I don't have the facilities to pull the pan in the driveway. That said, I'm not a total numbnutz when it comes to fixing things. I actually was trained as an automechanic, and certified (as an automechanic) by the Commonwealth of Virginia in high school. Which was about 30 years ago now. It's been about 29 years since I was employed as a mechanic. Hell, I even changed a light bulb last week while my wife was giving me the bejeezus about some other goofy issue. On a ladder no less!

Sympathy, derision, and advice appreciated.
I'd be much obliged for any good words from y'all.

Here are a couple vids that show how the TIME-SERT repair operates:

TylerSteez

iTrader: (3)

Have you contacted Jiffy Lube? I'm guessing they can't be held liable for this but who ever tightened that drain plug definitely knew it was stripped and tried to play it off like it wasn't.

W.E.G.

I won't be going that route. My objective is to fix it myself. I don't want this to be a thread about Jiffy Lube - but I felt obliged to mention how I got into the situation - people are always curious about such things.

sofakingdom

iTrader: (1)

OK so here's your virtual kick.

[kick] kick [/kick]

Seriously, there's no shame in using that kind of a place to change your oil. For the amount of time and mess control it saves, it's not a bad move at all. Especially if you don't have a good place to do it.

And of course, you can complain all you want about them stripping the plug; but plenty of folks have done it to their own cars in their own driveways, too.

They make "repair" drain plugs that are a somewhat lager size and that cut new threads. That's one option. Alternatively you can be a jerk, like me, and demand that they put on a new oil pan.

The solution you outline is also acceptable. The approx .7mm difference in hole dia should easily cover the missing threads. If you go that route, slobber your drill bit with grease, to catch all the chips; and pour some kind of solvent through it afterwards, to wash out any that get past the grease. Diesel fuel is probably the best choice. Put the plug in, pour in a gallon, wait a few minutes, take the plug out; let it sit for a few hours; then put the oil in and start it and all that.

W.E.G.

As I'm studying the insert that comes with the 1/2" TIME-SERT kit, I'm wondering whether the Chevy oil pan is going to have enough thread depth in the drain plug hole to allow this insert to "bite" the sides of the hole.

The insert operates by roughly the bottom third of the insert being expanded to grip the hole. I'm afraid that the hole will be too shallow to give the insert any meat to grip.

TylerSteez

iTrader: (3)

M12 converts to .472 thousands of an inch which is .028 thou under half of an inch. that leaves you with .014 thousands for your thread depth which isn't very much... the threads will look shallow and blunt.

When I drill and tap holes around that size I like to drill a hole that is around .050 thou smaller than the tap I'm using.

W.E.G.

I decided to go with an oversize drain plug. I figure I can easily drill/tap the hole later if needed, but once I start drilling, there's no going back.

For starters, here's the drain plug I pulled out of it this morning.

W.E.G.

And here is the condition of the oil pan after the plug came out.

W.E.G.

Comparison of the old plug and the oversize (oversize by 0.030").

W.E.G.

Nothing is ever easy.

My daily-driver is in a real shop today for brake work. Naturally, my metric sockets are in the tool-box in that car.

Biggest metric socket I have at the house in my box of orphans is a 14mm. Naturally, the head on the new plug is 15mm.

I tried running it in with a 5/8" --- which slipped. Hence, the buggered head on new plug.

I soon discovered that it was going to take some MAJOR elbow grease to run that ovesized plug into the existing hole. I managed to get it in using Dad's 10" Crescent wrench. Once I started working with the Crescent wrench, it didn't slip once. I knew Dad was watching, so I gave it all I could muster.

So I won't have to run around in perpetuity with an oil plug with a buggered head, I'll be sure to use a new plug when I pull this one for the next oil change. Once I got the new plug in, I wasn't about to unscrew it to "inspect my my work."

I did my very best to try to get the threads on the new plug to marry-up with the existing threads on the oil pan. All I can say is it seemed to be going in straight. The new plug was fighting me back (consistently at least) after I got it engaged about a half-turn. At least it it bottomed-out firmly when the flange on the plug met the oil pan. I stopped wrenching right there.

W.E.G.

I poured oil in it, and let it run for about 10 minutes.

Not one drip.

And that was a couple hours ago. Still no drip. Maybe I'll actually DRIVE it some tomorrow instead of fretting.