Broke headbolt off flush with block...

Ok, my worst fear in attempting to change a head gasket is now a reality.. I snapped of a bolt flush with the block.. I've <br />tried to talk with several machine shops and NOBODY wants to touch this.. I've ordered extractors from Snap-On, but I'm hoping someone can give me some good advice on how to proceed.<br /><br />In case your wondering... Yes, my wife has only reminded me a "few time" that I still have not fixed the boat.. <br /><br />Thanks in advance for you assistance!

Re: Broke headbolt off flush with block...

hello<br /> what motor ? what size bolt? did it break of at the block or head surface? which bolt and can it be acessed without removing the power head from the frame. do not I repeat DO NOT use any extractors. you will make a much bigger mess.<br />if your anywhere near chesapeake VA i can hook you up with several shops I can reccomend.<br /> good luck and post back with the requested info.

Re: Broke headbolt off flush with block...

If you can get at the bolt to drill it out and You feel you can do it. The key is the drill bits you use. You need to take your time and buy some really good drill bits. We use a special bit and use them once. Dont use the extractos they dont work and if they break off in the broken bolt Your really up the creek. We remove bolts all the time. The key is the first pilot hole you make must be perfectly centered on the broken bolt and go all the way thru the old bolt. Then slowly step up the size of the drill bits. We use a bit made to cut Stainless steel. We use it one time and throw it out. Works every time. Don't rush it and take your time. Chase the threads with a meter tap.

Re: Broke headbolt off flush with block...

Thanks for the replies guys! It's a 1993 225 Yamaha.. The bolt snapped flush with the block , I can get to it without removing the powerhead, they are right there. The bolts are (guessing.. I'm @ work now ) 12mm (close to a 3/8) in size.<br /><br />Wish I was near Chesapeake VA, I'd be very happy to take you up on your kind offer.. Used to live in Virginia Beach years ago, my father was in the Navy... Now live in Cape Canaveral Florida, due east of Orlando.. <br /><br />As for the special drill bits.. Where can I order them, what sizes would you recommend? <br /><br />Thanks Again!!

Re: Broke headbolt off flush with block...

Any Industrial supply store. We use a company called Fasten-All. There are two different length head bolts on that engine. If you can get a small hole thru the center of the broken bolt. You then go up two drill bit sizes and heat the out side of the block where the broken bolt is. Then take the larger drill bit and drill half way thru the broken bolt. After you have heated around the bolt slowly reverse the drill. If you have heated the block enough the broken bolt should come out. Apply heat all the way around the broken bolt.

Re: Broke headbolt off flush with block...

If push comes to shove, use a easyout when you heat the metal around the bolt so as to get a grip on it but be careful not to break the easyout off. There's a fine line when heating between hot enough to release the bolt and hot enough to melt holes thru the block. Last resort, you can drill out the old bolt and get a metric helicoil to replace the threads.

Re: Broke headbolt off flush with block...

HAVE BEEN THER BEFORE <br />WHY NOT USE A LEFT HAND DRILL BIT <br />WHICH IS AVALIBLE FROM MOST PARTS<br />STORES I USE NAPA GOOD LUCK

Re: Broke headbolt off flush with block...

hello<br /> I dont bother with all that money motion. the odds of breaking a bit increase with every hole. if the threads are stuck so tight they twisted off an 8mm bolt your not going to turn it with a brittle twist drill by hand. I use bullet point bits. the ones from dewalt have 3 flats ground on them to prevent slipping in the chuck. make sure the steering is locked hard over one way or the other so the motor does not move. drill away. if your not sure you can drill straight find some one who can.try a bit 2 letter sizes below the tap drill sive or carefully use the tap drill for 8mm. just be aware that 8mmx1 and 8mmx1.25 take different taps and drills. at worst you nick the threads and have to drill oversize and use a heli-coil. I do it a few times a week. a friend of mine uses a special rod that he welds to the broken stud. he then cuts off the rod and welds a washer and nut to it. then we heat it and while one keeps it hot the other backs the stud out. he charges55 dollars a stud. I only charge 45 a stud unless its already been drilled at or has a broken drill or easy out. then its a flat 100 per hour with a 1 hour minimum.<br /> good luck and keep posting