Broken Exhaust Bracket Mounting Bolt Extraction
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Hooked
2010 S50 Modified "Punkin"; 2003 ET4 150 "ISO"
Joined: 18 Feb 2017
Posts: 282
Location: Deepinnaharta, Texas
Sun May 31, 2020 9:40 am quote
Greetings:

Thought I'd record the Chase for this bolt segment stuck in the engine case as the Tecno pipe bracket sheared off the lower one.

I purchased these items on fEeBaY. The first is a small set of Left-Handed drill bits with matching screw extractors. I've had very good luck with the bits alone; when they start to bite into the segment, they tend to spin the thing out with no further action required. When I've had to go to Step 2, those screw extractors hardly ever work for me. The other problem I have is that the bolt broke off about 5 or so mm INSIDE the case, so the case threads are liable to be damaged if the drill bit goes off-center.

Enter the larger Kit in the orange plastic box. The little dowels are actually thread protectors that in theory should keep the bit near the canter of the broken bolt while protecting the threads. I figured I'd use the correct-size item WITH a Left-Handed bit, see what happens.

Oh, and I found a 10mm "wobbly" socket to ease the Pain of exhaust header nut removal. We'll see about that, too.

PunkinPipeEdit.jpg
The lower bracket bolt is the one that sheared off. The Tecno pipe bracket doesn't allow both holes to be precisely centered over the case holes, suspected cause for shearing.

ScrewExtractors.jpg
Left Handed bits upright, thread protectors and related extractors in the plastic bin.

Hooked
2010 S50 Modified "Punkin"; 2003 ET4 150 "ISO"
Joined: 18 Feb 2017
Posts: 282
Location: Deepinnaharta, Texas
Sun May 31, 2020 8:40 pm quote
Bolt Extraction
Greetings:

I could see my problem. Lower mounting bolt broke off in engine case. The bolt appears to go through a plastic sleeve for the cooling shroud before threading into aluminum engine case for roughly 1/2" or so. Not a lot of "meat" there, and I may add a nut on the backside as the mounting hole does not end blindly but goes right on through the boss in the case.

Closer inspection confirmed the off-centeredness of the lower mounting hole with the top bolt installed. Kind of looks like the BIC (Pens, lighters) logo. This probably caused some bending moment and with vibration added and a hardened Carbon Steel bolt, fracture was the end result.

Extraction of the bolt involved knocking in the drill guide sleeve, then a good deal of patience. The left-handed bits were no match for the hardness grade of the bolt. I went for a bit from my workbench, which still required a bit of patience before holing all the way through. The extractor kit calls for knocking in the long 1/8" dowel, then using a special nut attached to that dowel to back the broken segment out.

Both top and bottom mounting holes require a spacer, which from experience have proven tricky to install. I thought I'd super-glue it into place and perhaps simplify that step.

LowerMountBrokenbBolt.jpg

DrillSleeveInSitu.jpg

ExtractorBolt.jpg
VICTORY is MINE!! The dowel-looking thing gets knocked into the central hole in the broken bolt, then 10mm wrench Carefully removes it.

LowerMountSpacerSuperGlue.jpg
Super-glued spacer to case after cleaning both with Acetone.

Hooked
2010 S50 Modified "Punkin"; 2003 ET4 150 "ISO"
Joined: 18 Feb 2017
Posts: 282
Location: Deepinnaharta, Texas
Mon Jun 01, 2020 10:48 am quote
"
Greetings:

Wrapping up this little project. The bracket wasn't all that far off to center the 2 bolts. I ovaled one of the holes a little with a tiny grinding bit to give me the millimeter or so needed to achieve Dual Centrality.

The sheared-off bolt segment succumbed at length, but drilling this material was tough on bits.

Re-centered the bracket with everything just finger-tight and remounted at last.

BoltExtract.jpg

PunkinExhaustRemount.jpg

Addicted
2006 LX150 (carbed) | 2007 GT200
Joined: 29 Jun 2016
Posts: 926
Location: Toronto
Mon Jun 01, 2020 5:21 pm quote
Glad it worked out! Thanks for taking the time to document and share!
Veni, Vidi, Posti
Lx 50 4T, GTS 250, S 150 (Missing in KS), Something Chinese, GT 200 (sold)
Joined: 21 Feb 2011
Posts: 8417
Location: KS USA
Thu Jun 11, 2020 8:12 am quote
Nice explanation on extracting a bolt. 👍
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