Broken head studs

[Richard/Ca]

I know! here we go again. But all I would like to know is what size are the holes in the heads so i can get the right drill guides. I would like to try drilling the broken head studs. I would like to start with a 1/8 in. drill. I have about 8 to drill out in 3 blocks. Thanks Richard

[BILL WILLIAMSON]

Richard, can't help you with the sizes, but be sure to use a fairly powerful drill motor, that turns QUITE SLOW!! Bill W.

[BRENT in 10-uh-C]

Well it depends, anything under 7/16 but I would try to weld the washer & nut onto the broken stud first before drilling as many blocks have been damaged by a mis-aligned drill. This is an area where experience is your friend. When I need to drill one, I do it in my mill where I have control.

[Tom Wesenberg]

Yes, what Brent said, weld a large flat washer to the stud, then weld a nut to the flat washer. The two heat cycles will do a lot to help break it loose so you can back it out with the nut. If it breaks then weld it a second time. Has always worked for my on one or two welds.

I've also drilled them and one time a small bit caught and broke. I had to use a diamond bit in my Dremel to grind it out. I just would drill slow and easy and keep increasing the bit size until you just start to see the threads. Then use a pick to start pulling out the threads. A tap can also grab the threads and pull them out sometimes.

[Don/WI]

Brattons has a tool kit to accurately drill out a broken stud. Their part number is 08235. It works great. Good luck with your project. Don/WI

[pat in Santa Cruz]

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heres another vote for welding a washer and nut to the stud. After it cools to just warm, flood it with Kroil. Liquid Wrench or PB blaster. The cooling threads will draw the penetrant in. I use an air impact wrench, as the hammering helps loosen the stud.

heres a link to Vince's site on how best to perform this task:

http://www.fordgarage.com/pages/studremoval.htm

[700rpm]

I work on my cars as much as I can, but any of this kind of work is beyond my skill level. I just took my block into a machine shop and let them figure it out. When I weigh the aggravation, lack of welding experience, potential for trouble, and the cost for the special tools, I figure I'm ahead. I'm a big believer in letting professionals do professional work. If the engine's still in the car, though, you've got a different problem than mine.

"A man has to know his limitations." — Dirty Harry

[colin1928]

I also weld a nut when possible when I can not weld a nut I use a old cylinder head as a guide and use left hand drill bits marked for correct depth

[Richard/Ca]

Thanks all of you for your great advice. I would like to use the welding method but I only have an arc welder.Would a arc welder work? I have been putting Kroil on them every time I get around them for the last week.

[Purdy Swoft]

I've never had any luck with the washer and nut way. I use the head as a guide. I use the kit from Bratton. I then use the cutting torch to melt and blow the remaining steel threads out of the cast iron threads in the block. The torch doesn't damage the cast iron threads in the block. The torch only melts the steel threads. Its a nerve wracking job but works well for me.

[BRENT in 10-uh-C]

Originally Posted by Richard/Ca

Thanks all of you for your great advice. I would like to use the welding method but I only have an arc welder.Would a arc welder work? I have been putting Kroil on them every time I get around them for the last week.

An arc welder will work well if you have a small rod and are accurate with rod placement.

I realize this will come off as sounding biased but there really is no harm or shame in seeking a professional when circumstances like this arise. A professional machine shop will use an EDM or the welding trick and extract it for you without any damage. Often times the price with be from $25 - $50.

[BILL WILLIAMSON]

Originally Posted by Purdy Swoft

I've never had any luck with the washer and nut way. I use the head as a guide. I use the kit from Bratton. I then use the cutting torch to melt and blow the remaining steel threads out of the cast iron threads in the block. The torch doesn't damage the cast iron threads in the block. The torch only melts the steel threads. Its a nerve wracking job but works well for me.

Purdy,
NOT recommending this, But I've seen my friend, Ron, BLOW a 1/2" broken stud from a block, without even drilling, with a light duty cutting torch & the threads were left intact, with only a few tiny dingle berries left, that were removed easily with a pick! Cleaned the threads with a bottoming tap, & PERFECT!!
AGAIN, I DON'T GENERALLY RECOMMEND THIS FOR THE NOVICE OR THE FAINT OF HEART!! Ron's had years of experience doin' this!-----Bill W.

[montanafordman]

I had a neighbor use his mig welder to get mine out. Two were broken off flush with the block or slightly below, the other was broken off about a quarter inch above the block. It took him a few tries but he was able to weld a nut on there and extract the stud with no damage to the block. I think this method is much more desirable than attempting to drill it out.

[Purdy Swoft]

Originally Posted by BILL WILLIAMSON

Purdy,
NOT recommending this, But I've seen my friend, Ron, BLOW a 1/2" broken stud from a block, without even drilling, with a light duty cutting torch & the threads were left intact, with only a few tiny dingle berries left, that were removed easily with a pick! Cleaned the threads with a bottoming tap, & PERFECT!!
AGAIN, I DON'T GENERALLY RECOMMEND THIS FOR THE NOVICE OR THE FAINT OF HEART!! Ron's had years of experience doin' this!-----Bill W.

Bill, I have no doubt that it would work. Using drill guide bushings with the head makes drilling out most of the stud much easier. I don't have nearly as much molten metal flying when I blow the rest of the threads out with the torch. Its hard to do without getting burned a little. It can also be DANE-JUS !!!!!!! I wouldn't want to ass around and burn the shop.

[racer32]

Figured I'd pull this thread up to the top. I've been attempting to use my wire welder to remove some broken studs. Having a hard time keeping the nuts from just snapping off after I weld them on. Welder is Hobart 140 w/flux core. I'm about ready to give up, pull the engine, and put in small block Chevy. Any helpful hints?

[Bob C]

Is the washer breaking off also??

Bob

[hardtimes]

Originally Posted by racer32

Figured I'd pull this thread up to the top. I've been attempting to use my wire welder to remove some broken studs. Having a hard time keeping the nuts from just snapping off after I weld them on. Welder is Hobart 140 w/flux core. I'm about ready to give up, pull the engine, and put in small block Chevy. Any helpful hints?

What? racers don't give up !
Well, if you are going to pull engine anyway, and that's what I'd do in your case..i.e.- broken head studs. Then ,if you do pull engine, take the block to a shop that has an Electrical Discharge Machine. They can vaporize those studs and not even damage the threads...hard to believe, but true !
I have a shop close to home and found that that shop is a wonder/blessing both. Turns out they can do a number of services..and CHEAP, by comparison ...to buying expensive tools, learning to use them correctly/expertly, etc....

[Tom Wesenberg]

I don't like flux core, but turn the heat way up to max and slow the wire speed so you get the stud hotter. I have gas shield and the welded nut and washer has always worked for me. Sometimes the nut may snap on the first try, but it has always worked on one or two tries for me.

[racer32]

Originally Posted by Bob C

Is the washer breaking off also??

Bob

Yes. Can't seem to get a good weld onto what's left of the studs.
I'm wondering if it's rust/oil contaminating my welds. I tried to get the remnants of suds clean as possible, but it's hard to grind when they're right at or just below the block surface. All my attempts so far I've tacked the washer to what's left of the stud, and then filled the nut with weld. I tried more heat, but the washers would burn through.

[racer32]

hardtimes, what's the going rate per hole on EDM in your area? I'm in a small town, so it may not be an option anyway.