Stripped oil drain plug....

oh yes, I did.

So anyway, its in there, and no 8mm allen will take it out. I have several new plugs on order, but for now, i need to get this one out.

What is the preferred tool? A regular Irwin or Alden bolt extractor kit? Do i need to drill any more?

Better idea? I can;t be the first [idiot].

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

i need an "easy-out" type tool. There are many kinds. I guess i'm sufficiently charmed that i have limited experience...

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

No need for an easy out yet...
1. You can try a socket that is close (even SAE) and tap it in with a hammer.
2. Vice grips.
3. Take a chisel and hammer and tap on the outside edge of the drain plug (this worked for me)

Make sure you get a couple of extra plugs, or get a magnetic plug.

dghii
2000 Boxster S 6speed 112k miles

SAE sizes, as well as next allen, jump too radically to be possible.

Chisel....hmmmm dont want to hurt anything.

How did you grab with vice-grips?

I have several on order. From now on i'll change it every few oil changes.

Thanks for the suggestions.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Well the vice grips didn't work but I did try it a couple of different ways....around the diameter of the plug seemed like it might go but I just couldn't quite get it.

FWIW, the chisel made short work of the problem as the drain plug is quite soft. I chiseled in at an angle on the outer edge of the plug and within a few taps with the hammer, the plug started to loosen. I then used the a pair of plyers to keep it moving.

dghii
2000 Boxster S 6speed 112k miles

My project maybe for tomorrow eve as i just finished my tow hitch; wiring; bumper re-install; trailer check-out, etc. ZZZzzzzzzzz.......

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

drive into the drain plug tool bit hole and remove the drain plug.

I haven't kept up on what' 'easy out' like tools there are now so there may be something that is just what the doctor ordered.

If you can't find a suitable stubby easy out like tool then you can drill straight up through the center of the tool bit hole and through the drain plug -- stop drilling as soon as the bit breaks through -- then use a proper sized regular easy out to remove the drain plug.

If you are worried about drilling swarf arrange for a helper with a large/powerful shop vac to suck away the drilling chips/swarf. Have the oil filler tube cap removed to allow some air into the crankcase and thus support a flow of air from the crankcase through the hole and into the vacuum nozzle once the drill breaks through.

I would be leery of using a chisel to loosen/remove the drain plug or vice grips for fear of marring/damaging the very critical sealing interface at the oil sump drain hole.

Sincerely,

MarcW.

.. as you suggest, I first drill pretty much through the plug. Which, yes, i prefer to avoid.

I think the chisel idea is OK if i'm fairly gentle and tap[ at an angle, which is the idea anyway. I plan to create a ridge for it with a dremel or angle grinder first anyway.

We'll see when i'm under there with an array of tools. Many thanks for all the various ideas, cautions, etc.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

even though the operation is done with a hammer and chisel, gentleness is required.

Also, most chisels -- at least this is my recollection from several decades ago -- had their cutting edge centrally located. For chiseling things in two this is ok.

For chiseling things like a drain plug loose the cutting edge, the active edge, wants to be biased to one side so the force can be applied radially with the intent of course to loosen/unscrew the plug while at the same time minimizing the severity of the impact to the sump and avoid marring in any way the critical sealing surface at the drain hole.

In the machine shop I'd make up special chisels using high speed tool steel blanks (from 1/8" square to up to 1" square) and create the edge I wanted/needed for whatever chiseling job I was facing. For the layman unless a chisel with an offset edge is available over the counter fashioning one out of tool steel is generally not a viable option.

Sincerely,

MarcW.

If i have to generate the notch, then i would use a chisel. Yes, the angle is more acute that way - i dont like it either. but then, the car probably also gets shocked when it hits the curbing at 100 mph, time and again. So if i'm careful, i'm rally not all that worried.

Hope i don't eat my words. Thanks for reinforcing caution - the better part of valor as they say.

I now have 4 plugs, a snap-on easy-out, a drift and assorted other stuff. Looks like a cross-channel operation in prep.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Apply common sense and I promise you won't screw anything up! If it doesn't work for you, try something else.

Just because your plug is stripped does not mean that your plug is grossly over-torqued. The plug is soft metal.

I had changed the oil 4 previous times in my car without a problem. No one else has worked on the car. My intervals between changes were consistent. My car is garage kept. I have no idea why the last time I tried to change the oil, the plug was stripped.

Oh well. Tap, tap, tap and out came the plug.

dghii
2000 Boxster S 6speed 112k miles

Since they are made out of a harder material than the pan, the pan strips before the plug. In your case, in all likelihood you will destroy the plug getting it out and just replace it. The alternative is very expensive.

[www.rennsteig.us]

I also saw this proposed solution when I did a google search.

"If you have a Dremel tool, you can create a new slot with a cut off wheel. Then you can use a flathead screw driver."


BTW, don't beat yourself up for the gaff. Pro's do it too - they just have the tools to fix it (and you don't hear about it).

I did buy a screw extractor at SEARS, btui have my doubts about this particular one.

I may just leave it until after the Glen and have my local indie remove it.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

I have a Dremel. I'm a big fan, in part because of the myriad of attachments which allow for a fair bit of precision. An angle grinder might be a bit large and bulky.

There's no shame in handing it off to your independent, particularly if he's capable and careful.

Angle grinder seems much faster, and will create a more substantial channel to get something into ( chisel, screwdriver blade, etc.)

Problem taking it somewhere is time. My buddy offered. but that cant happen at night, so not until after 3 more days on the track, on already old-ish oil.

I'm glad it started life thicker than factory fi8ll...

Grant

gee-lenahan-at-gee-mail-dot-com

I've used this aftermarket drain plug from LN Engineering, and have been very satisfied. Also it has an oversized 10mm internal hex to prevent the problem many of us have experienced. No affiliation, blah blah blah.

- John L
Boston
'01 S

in the future i'll only remove them a few times.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

to damaging your drain pan, as described above. The stock part generally lasts forever (mine has been on for 165k miles) and it is designed to be "sacrificial" in the sense that it should be a soft non-hardened metal so that it strips before the oil pan does.

Very interesting thesis. Here's mine: Porsche cheaped out on the drain plug, which is prone to failure even when properly torqued. I'll stick with the benefits of a self-installed properly-torqued aftermarket drain plug, and stop worrying about stripped sockets or pan threads. I'm also not aware of a maintenance schedule for 'drain plugs', ergo, there's something amiss if one needs to purchase extras and replace preemptively / frequently.

Regards

I just use a new factory drain plug at each oil change. Never had a prob with stripped threads or leaks.

and I do quite a lot of listening.

Are you saying the allen/hex is the sacrificial part?

Nice of them not to leave a backup plan to get it out then!

My understanding is that Charlie's is aluminum; has a magnet for bitty specs of ferrous material; and has a deeper 10mm hex drive.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

The hex part is not meant to be sacrificial. The design is a bit deceptive. You can push the allen wrench in and think it's all the way in when it's not really. If you make sure it is all the way in, it won't strip. There is something strange/flawed about the design that leads you to think the tool is all the way in sometimes when it is not.

Edited 1 time(s). Last edit at 08/05/2012 12:44AM by Laz. (view changes)

Quote
Boxsterra
The hex part is not meant to be sacrificial. The design is a bit deceptive. You can push the allen wrench in and think it's all the way in when it's not really. If you make sure it is all the way in, it won't strip. There is something strange/flawed about the design that leads you to think the tool is all the way in sometimes when it is not.

The drain plug tool bit hole is a very tight fit on the tool bit. This is intentional to lessen the wear/tear on the drain plug.

The problem is one of inexperience.

Inexperienced people who do their own oil/filter services -- or take the car to a shop that doesn't really know what they are doing in this area -- do not fully insert the tool bit in the hole.

Part of the way in there is some resistance due to the tight fit of the tool bit in the hole. Believe it or not this comes from the air that gets trapped as the tool bit is inserted and pushed home. The fit combined with a bit of oil film on the tool bit -- not uncommon -- offers some resistance and as a result the tool is not fully inserted into the drain plug tool bit hole.

As the drain plug is loosened the bit twists in the hole -- because the bit is not fully inserted -- this twisting raises a burr at the end of the bit.

This burr then becomes a false stop so the next time the bit is inserted it is even less likely to be inserted all the way -- the burr sees to this because it offers much more resistance than the trapped air from the previous time -- and upon torquing the drain plug tight further damage is done. The damage is almost certainly made worse by those that do not use a torque wrench and thus probably over-tighten the drain plug.

So the next time the drain plug is removed the hex tool bit hole strips out.

With proper treatment the drain plug will last a long time.

The one in my Boxster lasted years until I took the car to a quick lube shop and the oil change tech was fooled into only partially inserting the tool bit in the tool bit hole. While he got the plug out and in again -- he used a torque wrench but wanted to torque the drain plug down to the industry standard 50lbft of torque vs. the proper torque but when he told me this I insisted he use the proper amount and although he told me he would I suspect he overtightened the drain plug anyway.

Anyhow, at the next oil change time I took the car to a dealer and the tech spotted the fact the drain plug hole had a burr. In order to avoid -- if possible the cost of removing the stripped out drain plug -- and he drove the tool bit all the way in. He managed to get the drain plug loose and removed it, but the drain plug was stuck to the tool bit.

Later after I left he managed to separate the two.

Before this, though, to get me and my car on our way, the tech loaned me a used drain plug and I bought two new ones and when they came in I gave one to him to replace the one he gave me and tossed the other one in the center console to have as a spare.

For those that change their own oil you must be sure the tool bit goes in all the way. Roughly it wants to go in around 1.5 times as deep as the tool bit is big. Thus a drain plug with an 8mm tool bit hole should have a hole at least 12mm (nearly 1/2") deep. The drain plug may even have a deeper hole. The 1.5 times comes from the rule of thumb regarding how much thread engagement a bolt should have in a threaded hole: it should thread in -- freely -- at least 1.5 times deeper than the diameter of the bolt.

Sincerely,

MarcW.

... using the wrong size allen wrench.
The correct size is 8 mm (0.3150 inch)
The wrong one is 5/16" (0.3125 inch).
This is slightly smaller and fits easily in the plug, but eventually, with tightening will start to round-out the internal hex.
Many people have a bunch of allen wrenches with metric and SAE mixed in.
Make sure the one you use for your oil drain plug is 8 mm.
When used correctly it will not screw up the plug.
I had the original plug in my engine at 203,000 miles with over 40 oil changes.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna