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First, can I just vent for a second and say how much I hate those soft aluminum bolts that Kaw uses on the engine block? They have an amazing tendency to stick-and-snap-off on the reed valve covers - guess it's the heat, crud from the exhaust, but they are just consistently a problem and I see no reason why four steel bolts couldn't have been used instead. 'Nuf said.

Anyway, I broke off the bolts when I was rebuilding Orleans (fixed 'em with JB Weld..sort of) and I've done it again on this new project bike. There's about 5mm of the threads sticking out from the engine, and I've been hitting it all weekend with PB Blaster. My guess is that when I go to turn it, however, it's just going to snap off closer in, so I bought a 6mm drill bit and a M6 x 1.0 tap to clean the threads when it comes to that.

That said, can someone walk me through the steps to drilling out the remaining bolt bit and cleaning the threads? I know I don't have much margin for error since I'm in the engine case...but any tips before I start drilling would be greatly appreciated. :hitanykey

Thanks in advance.
 

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CWO3 Navy (Retired)
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I just had to drill out the manifold stud and tap it to put my Jardines on. Looking at the bike I'd say you are fairly safe because you have the reed valve to keep any debris from going into the engine. Use oil (regular 3-in-1 will work) and drill in a little and back out to clear the debris. You might want to have a small vac available and suck out the shavings. Once you get it cleaned out, tapping it should be fairly easy. Line the tap up square to the hole and start the tap going in a little, then back out to clean out the debris and go again. Use lots of oil to help the tap cut the metal.
 

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Sometimes it helps to have an assistant line up the drill bit and tap horizontally and vertically while you're working so things stay square.
 

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Old Twistie Sticks Rider
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File the top flat. Use a center punch to dimple it in the center. Drill as suggested above. BTW they do make drills that turn CCW that could actually remove the broken piece while you drill. Start with a very small drill then go tone large enough for an easy out. In a pinch a small torx bit can be hammered into the stud to pull it.
 

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I've used screw/bolt extractors in the past with very good results. If it works (never had a case where it did not), then existing threads will not be damaged. No tapping needed, just buy a new bolt in the same size as the old.

You can find bolt extractors in most hardware stores, in all sizes and they are about the cost of a good drill bit (I picked up a kit with about 6 different sizes for about $20). Extractors are simple to use; apply penetrating oil (let it work in real good), drill a hole in the center of the broken bolt, screw in the bolt extractor (correct size to fit in the hole drilled) and use a breaker bar (or wrench with a pipe to extend the handle) to unscrew the broken bolt. The extractor has left hand/reverse threads, so it continues to bite into the broken bolt as you unscrew it.
 

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I've seen something called Grabit advertised on TV for use in removing stripped / snapped screws. I don't own a set, and have no idea whether it works as well as advertised, but it seems so that it'd be useful in your situation.

www.4grabit.com

--FA
 

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i normally try to grab it the bolt w/ vice grips and use some heat to get a bolt out, if that doesnt work ill either try to drill w/ a left handed bit and/or use a easy out, if not i weld a nut to it.... all else fails drill and tap. if u weld a nut to it it'll either work or it'll break off closer and it'll be harder to drill
 

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A friend told me a while ago, tip for removing broked bolts. Use WAX.
optimumly heat the parts red hot, quench first with water, reheat again, the stick the wax to it(any parifin wax,or candle wax). Usually the bolt will just turn out by hand.
 

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i normally try to grab it the bolt w/ vice grips and use some heat to get a bolt out, if that doesnt work ill either try to drill w/ a left handed bit and/or use a easy out, if not i weld a nut to it.... all else fails drill and tap. if u weld a nut to it it'll either work or it'll break off closer and it'll be harder to drill
+1 here.

Sometimes I even use a file to create two flat spots for the vice grips to get a better hold. Tapping the end with a hammer while applying torque works well too.

Heating it up just makes the bolt expand..thus making it tighter...using something to make it cold works better.


KM
 

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Linkmeister Supreme
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A friend told me a while ago, tip for removing broked bolts. Use WAX.
optimumly heat the parts red hot, quench first with water, reheat again, the stick the wax to it(any parifin wax,or candle wax). Usually the bolt will just turn out by hand.
I would be very leery of appling that much heat to the cylinder pot. You could damage it past the point of repair, IMHO.


+1 here.

Sometimes I even use a file to create two flat spots for the vice grips to get a better hold. Tapping the end with a hammer while applying torque works well too.

Heating it up just makes the bolt expand..thus making it tighter...using something to make it cold works better.

KM
X2 to filing 2 flat spots and tapping with a hammer while turning the bolt. I believe CRC has a penetrating oil combined with a freezing agent that may contract the bolt enough to break the corrosion bond between the bolt and the cylinder. A little shot of liquid propane from an inverted cylinder might work too, if you are willing to try it. Propane vaporizes at -44*F. You get vapor from a propane tank used for BBQ`s and RV`s when it is upright. DO NOT direct either at exposed flesh, as a freeze feels just like a burn as it heals.

A second idea to try, is put a pair of vicegrips in the freezer for an hour to chill them, before griping the bolt at the flat spots. Give it a minute or two for the cold transfer and contraction to occur before applying torque to the bolt.

Good Luck. I hope something suggested here works for you. :smiley_th
 

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Discussion Starter #14
Thanks for all the suggestions and reminders! The oil was the thing I was forgetting (guess you missed it that first time, too, kanuck!). I think I'll try a bolt-out, though I've had luck with those only once; but if that fails, at least the bolt is already flattened out to about where I can tap it. Definitely will be applying anti-seize to the new bolts, but they are steel. :)
 

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I've always had good luck using heat and some penetrating oil like WD-40. I always thought the heat was to break loose the corrosion and such, and when I heat, I heat the metal around the bolt to promote expansion around the bolt, (opening the hole) and keeping the direct heat off the bolt (minimizing it's expansion), though I know there's always some heat transfer.

Anyway, there's a million ways to do it Cindy, everybody has done something thats worked. Step one would be figuring out a secure way to grip whats left of it, and go from there.

Someone above mentioned a hot wax process and while I've heard good things about that, I've never tried it myself.

I always use a drill and "easy out" bit, or propane heat, vice grips, and some oil.


I've never had to go beyond either method myself.

Good luck.

(Spark plug threads are steel too, and another good spot for anti-seize. ;) )
 

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I've always had good luck using heat and some penetrating oil like WD-40. I always thought the heat was to break loose the corrosion and such, and when I heat, I heat the metal around the bolt to promote expansion around the bolt, (opening the hole) and keeping the direct heat off the bolt (minimizing it's expansion), though I know there's always some heat transfer.....
Well I think heat can help break down the "corrosion and such" and in most cases when used with an oil it makes the oil flow better into the areas that may need it.
But a common misconception is when you heat a large piece of metal, like a cylnder head, that has some smaller holes drilled into it..the metal expands , but in all directions, and that means those smaller holes actualy get smaller.. because the metal surrounding them is expanding into the empty space.

This was a physics question ..how large of hole in a metal washer needs to be to get bigger when heated. The answer is...pretty big. A thick 2 inch diameter washer with a 1/4 inch hole in it when heated expands ...making the 1/4 inch hole smaller. Drill out the hole to 1 -7/8 inches, the hole will get larger when heated. Somewhere in the middle of that is a size hole that will do neither..the washer expands to more than 2 inches in diameter but the hole stays the same size. Anything smaller will get smaller, anything larger with get larger.

And as always , a good solid whack with a BFH* helps in most cases too...



KM





(*Big ****ing Hammer)
 

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I don't know man, but I do know everytime I've done it, it's worked, (like I stated, so why (exactly) it works isn't too important to me). But thanks anyway, and on we go...

Cindy, I didn't re-read this whole thread, but here's a thread from the Verses on the subject:

Stuck Bolts
 

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Old Twistie Sticks Rider
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Cindy, I didn't re-read this whole thread, but here's a thread from the Verses on the subject:Stuck Bolts
I didn't read it all either, but saw someone mentioned "Kroil" rather than WD-40, "Kroil" is some very good stuff, it seems to creep into places that other stuff don't, shooters and hand loaders use it a lot, I had rather have it 2:1 over the other stuff, its creapy...lol...
Have a good one...Old Dog...
 
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