stripped 3/8 diff drain plug, how to extract?

There are countless ways to extract broken stuff. It all depends on the application, position and the materials. The best thing one can do as a pre task, task, is to generously soak in a penetrating oil. My favorite is ATF and Acetone mix.

It is rare, that if a bolt head has broken off, a drill in extractor will get it
Did not know that....I figured that a shop has an easy time getting broken bolts out....the only ones I've tried were small, and, I found that I could even drill a hole right through the middle, but could still not get the complete bolt out, what's left still frozen in the threads

quick question--what would you do if the other side is the exact same, but, not broken yet? Technically the caliper doesn't need to come off for pads...but it does for the rotor (Lexus LS430). So for now, the bolt can be left alone for years....
 
Did not know that....I figured that a shop has an easy time getting broken bolts out....the only ones I've tried were small, and, I found that I could even drill a hole right through the middle, but could still not get the complete bolt out, what's left still frozen in the threads

quick question--what would you do if the other side is the exact same, but, not broken yet? Technically the caliper doesn't need to come off for pads...but it does for the rotor (Lexus LS430). So for now, the bolt can be left alone for years....
LH drill bits. Keep stepping up. Eventually what's left in the "increasing inside diameter" relaxes and spins out rather than getting cut (drilling). Plus the heat (friction) from drilling REALLY helps.

As noted, lots of penetrant.

Most general auto shops aren't machine shops. Quite often I'll make a jig or bushings to act as a drill guide so I can start my first hole as concentric as possible (note you can buy such things for applications like exhaust manifold bolt patterns)

It's also best to know the minor thread diameter or tap drill size of the thread in question. If you start to get close to that and the remainder of the fastener is not backing out, it's time to maybe consider wedging something like a spline extractor in there to spin it out, or make sure you have a plan for thread inserts or just tapping the next size up when possible.

Most flat rate shops just can't invest the time and don't have a full selection of taps (incl STI taps), dies, LH drills, mill, lathe and a deep understanding of threads. It's not rocket science and mechanics aren't stupid -- it's just not their specialty.
 
Did not know that....I figured that a shop has an easy time getting broken bolts out....the only ones I've tried were small, and, I found that I could even drill a hole right through the middle, but could still not get the complete bolt out, what's left still frozen in the threads

quick question--what would you do if the other side is the exact same, but, not broken yet? Technically the caliper doesn't need to come off for pads...but it does for the rotor (Lexus LS430). So for now, the bolt can be left alone for years....
Pretreat with penetrant of your choice. vPB blaster works well, but as before, I have had luck with ATF and acetone in a dropper bottle. shake before each use as they do not mix well.

I think a lot of times, mechanics at shops dont have time to mess around and wait for penetrating oil to do its thing. Things are procedure based...Step one, remove bolt, etc. if the bolt breaks, for them it is easier, less liability and more profit to sell tou a new part.

With no prior experience with this to tou I would recommend pb blaster.

same goes for everything else that might be suspect, fastener wise.

It can only help.
 
Yep, time is money. Even if you weld a nut on a lot of guys prefer to then let it cool on its own as expansion and contraction is significant.

I was just watching WWW and he prefers to "shock" it cold with a spray bottle.

I usually go at it while still hot, but our rust here is minor. If it doesn't move when hot, I'll try again once it cools.
 
Pretreat with penetrant of your choice. vPB blaster works well, but as before, I have had luck with ATF and acetone in a dropper bottle. shake before each use as they do not mix well.

I think a lot of times, mechanics at shops dont have time to mess around and wait for penetrating oil to do its thing. Things are procedure based...Step one, remove bolt, etc. if the bolt breaks, for them it is easier, less liability and more profit to sell tou a new part.

With no prior experience with this to tou I would recommend pb blaster.

same goes for everything else that might be suspect, fastener wise.

It can only help.
With the experience of extracting bolts, how would you approach one that is stuck, but not broken? Maybe penetrant and heat, and not even having to remove it immediately? Meaning maybe repeated application and trying on different days? This is the scenario with my rear lower left/driver side caliper
 
Yep, time is money. Even if you weld a nut on a lot of guys prefer to then let it cool on its own as expansion and contraction is significant.

I was just watching WWW and he prefers to "shock" it cold with a spray bottle.

I usually go at it while still hot, but our rust here is minor. If it doesn't move when hot, I'll try again once it cools.
It’s amazing to me, like many things, how something so simple can escalate. I asked the shop should we put antizeize? They said no. As a matter of fact if you look at your new bolts, there is thread locker (there is, red). If anything he said maybe silicone to cover the exposed opening. Dunno seems like a can’t win scenario due to design. If I had known maybe I’d take it out yearly. I last did it 2018 and no issues. 6 more years of salt….

At any rate hope all this discussion helps the OP and having some ideas on his issue…
 
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With the experience of extracting bolts, how would you approach one that is stuck, but not broken? Maybe penetrant and heat, and not even having to remove it immediately? Meaning maybe repeated application and trying on different days? This is the scenario with my rear lower left/driver side caliper
I would just pretreat with penetrant. Tap around the area with some quick taps with a small hammer, not Thors hammer....., and repeat over a few weeks I what suggesting a dropper bottle, because spraying could get on the brakes. Also, using a dropper bottle is more precise and you use less oil.

The danger of this is, you dont know if it is stuck, until it breaks.

How would I approach it, if I had to remove it?

Pretreat for several days.

Try to remove=no good, then heat

If still no good, break it off and get to drilling as @D60 explained.........

Usually pretreating for several days does the trick, outside of a ridiculous amount of rust and time. I recently removed exhaust manifold studs out of a 25 years old engine, and the pretreat was key.

I would also suggest use of a wrench, not a ratchet as it loads the bolt more perpendicularly to the fastener.

Good luck.
 
Heat**, cool a bit, lightly rap on it a bit, apply penetrant (CRC 5-56) rap it a few times more.

Next day. Drill deep a couple bits smaller than the thread, use E-Z Out - or similar.
Never did not work. - Arco
____________________________________________________________
**skip the heat if near gas tank or evap system
 
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Keep in mind, that if the bolt has a wide flat flange, penetrant probably won't get to the threads.
This is true. I wonder what it looks like from behind, the axle shart should be there too and tight
I would just pretreat with penetrant. Tap around the area with some quick taps with a small hammer, not Thors hammer....., and repeat over a few weeks I what suggesting a dropper bottle, because spraying could get on the brakes. Also, using a dropper bottle is more precise and you use less oil.

The danger of this is, you dont know if it is stuck, until it breaks.

How would I approach it, if I had to remove it?

Pretreat for several days.

Try to remove=no good, then heat

If still no good, break it off and get to drilling as @D60 explained.........

Usually pretreating for several days does the trick, outside of a ridiculous amount of rust and time. I recently removed exhaust manifold studs out of a 25 years old engine, and the pretreat was key.

I would also suggest use of a wrench, not a ratchet as it loads the bolt more perpendicularly to the fastener.

Good luck.
Thanks I have technically 5 years to wait, I can certainly try penetrant. It would have to be from the hub/drive axle area out, and I’ve not looked myself (didn’t think of any of this when I was doing the brakes). My drawn arrow shows where I’d need to spray.

Imagine this is the left rear, and the back of the vehicle is to the left. Those two long bolts hold the caliper to the spindle/knuckle

There are no threads where the head meets the caliper

IMG_3962.webp
 
hey all found out the 3/8 drain plug for my rear diff is stripped/rounded off. it looked pretty rusty too

any ideas how to get it out?

i did some reading and maybe this harbor freight pipe extractor would work?

i attached a pic of what i mean by the 3/8 plug (just a google non rounded pic) and also what i saw at harbor for extracting

ty!



View attachment 254786

View attachment 254803
Did you get it out yet? Just curious as to what worked. Thanks
 
Keep in mind, that if the bolt has a wide flat flange, penetrant probably won't get to the threads.


Do you think threads just float in mid air? The relationship between the threads is much tighter than a flange, but yet the penetrant gets through to the inner threads.

If your statement is true, the oil would not penetrate beyond the surface, flange or not.

Granted in would make it more difficult for the juice to get to its home.
 
I think penetrants are a mixed bag. Oftentimes just a feel-good measure for me. But it's a low cost, easy thing. Even if it helps 2%, I'll take it ;)
 
Do you think threads just float in mid air? The relationship between the threads is much tighter than a flange, but yet the penetrant gets through to the inner threads.

If your statement is true, the oil would not penetrate beyond the surface, flange or not.

Granted in would make it more difficult for the juice to get to its home.
Ever notice how if you start a bolt part way, it still wobbles? The threads aren't 100% full contact, or you wouldn't be able to turn the bolt readily, or get an accurate torque reading. The side toward the bolt head (when tight) is full contact, the 'lower/away' side is not (there's a gap). There's room for the penetrant to...penetrate.

A better illustration is probably a nut on a bolt, threaded on halfway up the bolt. Notice that it wiggles.

On the topic of severely stuck fasteners, I had to change the heating elements in our water heater (20 yrs old). They...did not want to move. Have the proper socket, so I gathered my toolkit...22oz hammer, 1/2" drive ratchet and the socket. Spent 30+ minutes on each one, holding the socket squarely on the element with one hand, smacking the ratchet handle with the hammer firmly with the other. Both eventually let go and threaded out easily. Plumber would have given up and sold us a new water heater. Lol. A technique that's existed since before impacts became a thing, and in fact, is what an impact is mimicking. The old school method is more gentle, if more time consuming.
 
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Didn't read the whole thread, but if all else fails, you can usually jack up one side, pull a rear axle and fill it through the axle tube. Just be sure to put in the exact amount it calls for in the manual.
 
If you want the Q&D approach, clean out the head as much as possible. Hit it with any torch you have, incl just a small LP or MappPro. Find a Torx that'll almost fit then drive it in with a BFH.

Then use an impact. Push in HARD and use very quick trigger blips. If the Torx starts to spin rather than bite, stop, drive it in more if possible, and repeat.

I've done this successfully, but there are several variables and YMMV. It uses common tools and you can get a plumbing torch head and LP canister CHEAP. MappPro (2008+) only burns a couple hundred degrees above LP
Clean dirt out of socket. Failing to do this is causes the problem. Use the ball side of a ball peen hammer. Use it to hammer wallowed out metal back into the socket. Continue until you need to drive the proper tool into the socket with the hammer.
 
Ever notice how if you start a bolt part way, it still wobbles? The threads aren't 100% full contact, or you wouldn't be able to turn the bolt readily, or get an accurate torque reading. The side toward the bolt head (when tight) is full contact, the 'lower/away' side is not (there's a gap). There's room for the penetrant to...penetrate.

A better illustration is probably a nut on a bolt, threaded on halfway up the bolt. Notice that it wiggles.

On the topic of severely stuck fasteners, I had to change the heating elements in our water heater (20 yrs old). They...did not want to move. Have the proper socket, so I gathered my toolkit...22oz hammer, 1/2" drive ratchet and the socket. Spent 30+ minutes on each one, holding the socket squarely on the element with one hand, smacking the ratchet handle with the hammer firmly with the other. Both eventually let go and threaded out easily. Plumber would have given up and sold us a new water heater. Lol. A technique that's existed since before impacts became a thing, and in fact, is what an impact is mimicking. The old school method is more gentle, if more time consuming.
no but when you tighten the fastener there is a seal, toward the front of the thread, toward the hole opening. this is metal to metal

i have had penetrating oil, on a flanged bolt, on the vertical, and the juice went to the threads
 
no but when you tighten the fastener there is a seal, toward the front of the thread, toward the hole opening. this is metal to metal

i have had penetrating oil, on a flanged bolt, on the vertical, and the juice went to the threads
Yes, and on the backside of that first thread is a gap.
 
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