Stripped allen bolt head (not threads)

[KTL]

If you've got it mangled so much that the head can't accept any kind of substitute tool anymore, just grind the head clean off with your dremel. When you get the other bolt off cleanly, you should be able to pop the U-shaped clamp off and then deal with the bad bolt shank w/out the steering shaft in your way

[steely]

Update - the bolt is out - my thanks to all for the tips. You and this place are really appreciated.

Short story: Impact driver and bolt-out baby.

Longer story: The dremel grove didn't work (for a screwdriver), over-sized bit combos no good, shovel snow, purchased bolt-out size too big, go back for right size (~13mm), shovel snow, go back for impact driver, go back for adapter, nurse back. Oh, and the sealant was just marker paint. Grinding may have been next.
Saved $60 on part, got some new tools (ignore math).

[slow&rusty]

Bumping this thread! I ran into the same problem with the same two bolts in the smugglers box trying to remove the steering rack yesterday. The thread was excellent and very helpful and I am on the way to buy a bolt-out this morning! Crossing fingers. I hate these damn allen female bolts..arghhh..time to replace with normal hex head stainless hardware.
Yasin

[PacificP]

ok guys i have done this a thousand times, just take a ballpin hammer and smash/deform the head in a little and place the right size allen wrench back in with a hammer, while your smashing/deforming the head, the pounding breaks loose any glue or locktight and the striped bolt comes right out! this is regular problem with my 80cc shifter kart and we have to pull striped out allen srcews at the race track between heats all the time. its fast and easy.

[slow&rusty]

Originally Posted by PacificP

ok guys i have done this a thousand times, just take a ballpin hammer and smash/deform the head in a little and place the right size allen wrench back in with a hammer, while your smashing/deforming the head, the pounding breaks loose any glue or locktight and the striped bolt comes right out! this is regular problem with my 80cc shifter kart and we have to pull striped out allen srcews at the race track between heats all the time. its fast and easy.

Sadly on the later model cars (mine is a 1989) there is a ton of HVAC crap in the way that negates the ability to use, fit or swing a ballpin hammer.
My car for example, and yes the bolts are rounded...grrrr.


Yasin

[911pcars]

Originally Posted by PacificP

ok guys i have done this a thousand times, just take a ballpin hammer and smash/deform the head in a little and place the right size allen wrench back in with a hammer, while your smashing/deforming the head, the pounding breaks loose any glue or locktight and the striped bolt comes right out! this is regular problem with my 80cc shifter kart and we have to pull striped out allen srcews at the race track between heats all the time. its fast and easy.

Brute force should be a last resort, especially with non-ferrous metal under that bolt head.

Sherwood

[PacificP]

i did not say beat the crap out of it. a few light blows with about 6 inches of travel
it does not take much to reshape the rounded out allen head. this is not a guess on how to remove the stripped head, i do this regulary

[Trackrash]

If you have an air chisel aim it on the outer edge of the bolts head at a slight angle. If you have the room it will eventually loosen it. It has worked for me.

[1990C4S]

Put valve grinding paste on the 'extractor'. It will improve the grip.

[DRACO A5OG]

Heck I saw just saw the Nat Geo show about Los Angeles Dismantlers they used a chisel and broke the nut loose then spun it off.

[Jayboundless]

So, I went to change out my shifter assembly bushings and one of the allen bolts that attaches the shift rod assembly to the main housing stripped out. I plan on hopefully using a "bolt-out" to remove. Does anyone know if our host carries that allen bolt? I can't find it. Or do I need to go OEM from dealer. Or does anyone have another source in mind?

[JAR0023]

If you are going to drill out a bolt head you may have better luck with a set of reverse drill bits. It's not uncommon during the process of drilling out a bolt head that a reverse bit will 'bite' and simply back the bolt out. Which is what you wanted in the first place. I do own some easy-outs but I've gotten more mileage out of my reverse drill bits. -J

[JAR0023]

Originally Posted by Jayboundless

So, I went to change out my shifter assembly bushings and one of the allen bolts that attaches the shift rod assembly to the main housing stripped out. I plan on hopefully using a "bolt-out" to remove. Does anyone know if our host carries that allen bolt? I can't find it. Or do I need to go OEM from dealer. Or does anyone have another source in mind?

Porsche calls it a conical set screw. Search part # 90142422900. Less than $5 from Pelican. -J

[911pcars]

This may sound a little drastic, and you may wish to save for last resort, but it works - depending - if the thread isn't frozen in place with Loctite or equivalent. If you suspect a locking compound was used, heat the fastener red hot to break the bond, allow to cool, then proceed as follows.

I've used the following technique to remove a flywheel bolt with a wonked internal hex.

Select a twist drill slightly greater than the thread size (D). See below. Drill into the internal hex (J), far enough (H) to remove the bolt head. No further. The internal hex will tend to center the drill, but keep the drill motor on-axis while drilling. Removing the bolt head should relieve any tension it created to hold the parts together. After separating the parts, unscrew the remainder of the bolt by hand or with a pair of pliers/vise-grips.

If more leverage is needed, apply double nuts if enough exposed thread or grind a thin slot in the shaft to fit a large blade screwdriver. A SD with a square shank can provide more torque when applied with a wrench. If more torque needed, weld a hex bolt onto the remains of the threaded fastener. Application of heat and Kroil also help.

Removing the head with a drill is more controllable and precise as it minimizes collateral damage as a result of stray hits with a hammer and chisel (could be acceptable in some situations, e.g. exhaust system, etc.).

Larger fasteners (i.e. flywheel bolts), require larger drill bits and more twisting force to cut. A 1/2" drive drill motor will work better with decreased cutting speeds required of larger drill bits and increased strength fasteners.

Sherwood

[Jayboundless]

Sorry jar0023, it is not the conical screw but a panhead screw the goes into the L-shaped bracket the holds the shift rod. I have the part number but it is special order. Is there an alternate or does anyone know if I can source at a local auto parts store?

[911pcars]

Originally Posted by Jayboundless

Sorry jar0023, it is not the conical screw but a panhead screw the goes into the L-shaped bracket the holds the shift rod. I have the part number but it is special order. Is there an alternate or does anyone know if I can source at a local auto parts store?

Typically, there are two M6 hex head or internal hex bolts that clamp the shift housing and the shift shaft L-bracket to the tunnel. One or the other should be readily available at a local hardware store.

Sherwood

[JAR0023]

Here's a clip from PET. M8X20 and M6X20 should be available at a big box like Home Despot or preferably your locally owned real live hardware store. -J

[daleflesburg]

Get some epoxy weld stuff at FLAPS and a cheap allen of the right size. Epoxy the allen wrench into the stripped bolt. Let harden. Put wrench on allen and back it out.

[Jayboundless]

It's the M6. Thanks for all the tips.

Cheers,
Jay B.

[RWebb]

some energetic person should summarize the several threads on this issue, and list the techniques in order of what to try first, etc. etc. down to last resort

then note the issues regarding lack of clearance and different materials (Al, or nearby plastic, which would make use of a torch contraindicated)