Tricks for rounded off head bolt?
 

Anyone have any great tricks for removing a stubborn head bolt? I tried to pull the heads on a Mark V 454 this weekend, and one bolt (there's always one) was so corroded the socket just rounded off the head. It was SO corroded in fact, I was able to tap a 7/16" socket onto what was left of the original 1/2" head, and for a brief moment, thought I had it. Then, of course, the smaller socket just rounded off what was left. What's the best option? Drilling, grinding? I vaguely recall attempting to drill off a head bolt in my younger days, with not-so-great results. I'd hate to trash the head...
Thanks.

Re: Tricks for rounded off head bolt?
 

I have welded a nut on top of a rounded off bolt before and it has worked. But I'm not sure if you would want to try that on a head bolt.

Re: Tricks for rounded off head bolt?
 

Weld a nut on top of the head of the bolt. Use a big enough nut so you can get a good weld inside the nut and to the top of the bolt. If there's room, use a nut that will go over the bolt head and weld it on. If you break the nut off, try again to get a better weld. I've been doing this for years and it works great. Tape off all the area's around it so you don't get welding spatter stuck to everything. If you don't have a welder, look into having someone with a portable one do it for you.

Re: Tricks for rounded off head bolt?
 

Craftsman has a set of removal tools called "Bolt-Outs". Have used them with great success on rusted/rounded off manifold and head bolts.

Dave

Re: Tricks for rounded off head bolt?
 

I've used the bolt outs and they work. Make sure you get the complete set, the one with 8 i think. I had several that wouldn't break free, I ended up sheering the heads off , then used a torch after I removed the heads.

Re: Tricks for rounded off head bolt?
 

I've use the nut technique several times with great success.

Re: Tricks for rounded off head bolt?
 

A little heat works wonders....

Re: Tricks for rounded off head bolt?
 

drill the head of the bolt.use same drill size as bolt

Re: Tricks for rounded off head bolt?
 

Ok but he asked about removing a bolt.... :p :p

Re: Tricks for rounded off head bolt?
 

crasftmans make s afew good products

they the "bolt outs" that are like sockets with helical cuts inside them. When you crank it down the helical cuts dig into the head of the bolt and crank it out.

they also have "screw outs" you drill a hole into the rounded head and then run these things in. They dig into teh hole and crank em out that way.

You can also try a left handed drill bit OR a combo of a left handed bit and these heavy duty screw outs that snap on makes. They have big wide threading on them like teh bolt outs but functions like the "screw outs"

Re: Tricks for rounded off head bolt?
 

I've also had good luck hammering metric size sockets onto the bolt head. What the others said will work to.

Re: Tricks for rounded off head bolt?
 

TEWKS,
I have had success with a combination of what you have alreday received as replies...I.E. I have drilled the center of the head of the bad bolt, drill size of about 70% of the size of the stem of the bolt, ( not the head of the bolt)
Clean up the chewed up outer edges( rounded portion ) with dremel tool and pound on a metric socket.
I used an impact driver for removal. I expect 1 of 2 possibilites as a result.
Either the bolt loosens, or the head, of the bolt, breaks off. If the head breaks off, use the dremel to remove whatever is left that obstructs the removal of the head. You can work the stud out of the block with vise grips, heat, & your favorite penetrating oil.. etc. Use plenty of rags to prevent debris from the dremel entering the engine. Heat the block and not the stud. Blow torch is fine ( moderate heating ) cool the stubborn bolt ( makes it shrink ).. usually
attaching vise grips cools it down pretty good...
Good Luck.

Re: Tricks for rounded off head bolt?
 

TEWKS,
After re-reading your original thread, I realize that you don't have much of the bolt head left. Dremel has a cut off wheel, they are delicate, but if room allows, you could cut what remains quite cleanly. These cut off wheels are about the size of a quarter in diameter, and very thin.
Sorry for all of my previous verb-age.
Doug

Re: Tricks for rounded off head bolt?
 

You have had some good tips to help with your problem, I have had luck using one or all methods mentioned, but I also would suggest taking a LARGE punch or similar tool and smacking straight down on the bolt head with a hammer.This will sometimes relieve surface tension and sometimes free rusted bolts.

Re: Tricks for rounded off head bolt?
 

\Thats what I usually end up doing. Once the head is off, pipe wrench on the bolt shank.

Re: Tricks for rounded off head bolt?
 

try vice grips always works for me

Re: Tricks for rounded off head bolt?
 

http://buy1.snapon.com/catalog/item....re&dir=catalog


These are the ones you want. I have used the crafsman version and they work ok once or twice but after that they get too mualled up to work. also the smaller pieces in this set work well to grip the shank of the bolt if the head has broken off.

Re: Tricks for rounded off head bolt?
 

welding should work.

Re: Tricks for rounded off head bolt?
 

had one do that last year on a 502 was the short outer bolts VERY CAREFULLY cut the head off with a torch pulled the head off and vice grips took the remaining stud out. we were installing a set of darts so we werent too worred about messing the head up but it didnt hurt it at all.

Re: Tricks for rounded off head bolt?
 

I had some also .Ck out my thread

http://www.offshoreonly.com/forums/s...highlight=head

Re: Tricks for rounded off head bolt?
 

Thanks for all the advice. Here's an update... Heat and liberal 'pounding' had no effect in this particular instance, though a good suggestion in general. I bought a set of the craftsman bolt-out's, absolutely useless (in my opinion) for this application. They just stripped out internally on the first turn. I'd wager they would work well on manifold bolts, but those head bolts are tough. The welding option sounded good, but not an option for me skillwise. What did work was the dremel with the heavy duty cutoff wheels. I just settled into the bilge for the duration, enjoying that warm florescent glow of sun-lit shink-wrap, and let the sparks fly. Elapsed time, 1hr 10min, and used approx 8-10 disks. Good experience for me, as I'll probably be going through the same process on the starboard side in another year or so :)

Re: Tricks for rounded off head bolt?
 

One I learned about reverse drill bits, I never had a problem again. Most times as I start the drill the bolt will come out.

Re: Tricks for rounded off head bolt?
 

Good Stuff!! Way to have a positive attitude for such a shi**y job!

Re: Tricks for rounded off head bolt?
 

hillbilly is right,I work on cars every day and boats they work great.

Re: Tricks for rounded off head bolt?
 

Exact situation happened to me. I tried EVERYTHING short of using a torch to cut the head off. Nothing worked. Then I used a DREMEL with a 1" cutoff wheel. I diced the head (because it was recessed in the head) and used a cold chisel and a baby sledge to bust off the small sections. The bolt is hardened and the cut sections easily snapped off. What was left was the bolt shoulder which just allowed the head to pop right off, no problem.

...And to think I wasted 3-4 hours with all of the other methods...ugh... :mad:

Good LucK!

-Larry

Re: Tricks for rounded off head bolt?
 

Do not use a torch to cut the head off. Use a torch to cherry red what is left to the top of the head bolt. while it is red hit it very very hard with a drift pin or a ball peen to relieve the tension. do this individual to all the bolts. then after they have cooled, or cooled some start over with a set of impact sockets. preferably 6 point. cherry the head again and pound the socket on. wait for a min or two to cool and spin out. The first heating will relieve tension. It will grow in length and buy letting it cool fairly slow it will change the metallurgical structure of the Steele. then cherry it again so you can forge a new shape such as a smaller socket size on it. I have done this on up to 2.25 socket head bolts that were almost completely corroded off In a recycled fiber paper mill that has high clorine content. have a good time but it always works and no special tools needed.