Broken Head Bolt
Thread Starter
Melting Slicks
Joined: Aug 2004
Posts: 3,078
Likes: 101
From: Riverhead New York
Broken Head Bolt
I'm working on my 454 out of our boat. I'm replacing the head bolts as a preventive maintenance issue. I'm hoping to not remove the heads. Heads of two cylinder head bolts are so rusted nothing will grab them. I've tried the new type sockets that are made for this and they just chew threw the bolt head making it even smaller. Tomorrow I'm going to drill off the remainder of the bolt heads and try to remove the bolt stud Anyone have another idea? I'd really like to avoid removing the head. Thanks, Al W. 
Race Director
Joined: Feb 2004
Posts: 11,039
Likes: 2,592
From: Del Boca Vista FL
Sorry but IMHO that head is coming off. If you are successful in getting the remainder of the deteriorated bolt head off without fubaring the cylinder head boss you will be granted status as a wizard.
But I have never seen anyone have the ability to center drill the remainder of the head bolt and remove it from the block with the head remaining on the block. It is my belief that even with the torque stress removed the threads will not release in the block and permit you to extract the remaining portion of the head bolt. If you are successful with that one on two bolts you are even more than a wizard.
My own luck is that the wizard would not see me in a situation like this.
While you are that deep in pull both sides and replace with ARP or some other type of high quality head bolt.
Best of luck.
Rich
But I have never seen anyone have the ability to center drill the remainder of the head bolt and remove it from the block with the head remaining on the block. It is my belief that even with the torque stress removed the threads will not release in the block and permit you to extract the remaining portion of the head bolt. If you are successful with that one on two bolts you are even more than a wizard.
My own luck is that the wizard would not see me in a situation like this.
While you are that deep in pull both sides and replace with ARP or some other type of high quality head bolt.
Best of luck.
Rich
Race Director
Joined: May 2006
Posts: 15,554
Likes: 555
From: Eagle, Idaho
Birdcage is spot-on.
The head bolts in a marine application like yours are probably rusted from the salt or fresh water recirculating through the block. The head bolts are in the water jacket of the block. Now you are trying to remove them and the threads could actually be galling or seizing to the block due to rust. In a closed loop cooling system, antifreeze or other rust inhibiting solutions keep this from happening.
We always prefered head studs as opposed to head bolts. We've installed the studs with Permatex and have never had any regrets. A lot of times pulling a head may mean pulling the motor due to hull clearance issues, but it's worth it.
FYI, ARP makes your choice of studs or bolts and the quality can't be beat.
Keep us posted and good luck!
RG
The head bolts in a marine application like yours are probably rusted from the salt or fresh water recirculating through the block. The head bolts are in the water jacket of the block. Now you are trying to remove them and the threads could actually be galling or seizing to the block due to rust. In a closed loop cooling system, antifreeze or other rust inhibiting solutions keep this from happening.
We always prefered head studs as opposed to head bolts. We've installed the studs with Permatex and have never had any regrets. A lot of times pulling a head may mean pulling the motor due to hull clearance issues, but it's worth it.
FYI, ARP makes your choice of studs or bolts and the quality can't be beat.
Keep us posted and good luck!
RG
Race Director
Joined: Nov 2000
Posts: 10,340
Likes: 664
From: Beverly Hills (Pine Ridge) Florida
One method of bolt removal (but must be done safely), is to weld a new nut onto the existing damaged bolt head to provide a new hex. But if the threads are that corroded and seized, you are probably looking at major engine block issues as well (and heads, manifolds, etc. - you get the picture).
I agree that for your boat application, probably best to yank the heads due to the corrosion issues.
I have worked on an engine with studs that were severly corroded. It actually makes the process worse! Ever try to pull the head off over the studs that are all corroded to the head bolt through holes? The head simply would not move at all. Took several days of soaking with penatrating oil and wooden wedges. Note that on this engine, there was no way of rotating the studs without the head removal. Proper maintenance is everything.
Plasticman
I agree that for your boat application, probably best to yank the heads due to the corrosion issues.
I have worked on an engine with studs that were severly corroded. It actually makes the process worse! Ever try to pull the head off over the studs that are all corroded to the head bolt through holes? The head simply would not move at all. Took several days of soaking with penatrating oil and wooden wedges. Note that on this engine, there was no way of rotating the studs without the head removal. Proper maintenance is everything.
Plasticman
Last edited by Plasticman; Jun 19, 2006 at 11:10 PM.
Racer
Joined: May 2003
Posts: 391
Likes: 36
From: taunton mass
broken head bolt in marine application
about 35 years ago a marine mechanic told me of a trick he used on corroded bolts on outboard engines he would take a battery and connect jumper cables to it and then gorund the engine with the negative lead and then after assuring ther were no flamibles present he would make contact with the positive lead on to the stuck bolt it would heat the bolt pretty much cherry red and break the corroded seal between it and the part it was connected to . I have used this method to free frozen bolts muself using battery power and on occasion a welder . It works like a charm you just have to be very careful about fire issues . Once its free your special socket may work. I hope this helps. Jeff
Le Mans Master
Joined: Jul 2001
Posts: 8,071
Likes: 317
From: Central Florida
That;s exactly how we did it in the US Coast Guard to remove bolts on diesel engines..... Just make sure you are not near ANY flamable liquids or vapors in the area...do it outside if possible or allow fans to be going full blast. Doing the weilding on those type of bolts is rather tricky especially while on the manifold.....
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Thread Starter
Melting Slicks
Joined: Aug 2004
Posts: 3,078
Likes: 101
From: Riverhead New York
Welding Bolts
OK! I've read your ideas and tomorrow is the day. ARP bolts are in the garage already and FYI I installed a closed cooling system when I bought this fresh water only boat. I'm a little afraid to connect a battery to the bolt but fear is no factor to fixing this thing! Thanks to All, Al W.
Safety Car
Joined: Feb 2003
Posts: 4,068
Likes: 27
From: St. Joseph Mo
Originally Posted by quahog
about 35 years ago a marine mechanic told me of a trick he used on corroded bolts on outboard engines he would take a battery and connect jumper cables to it and then gorund the engine with the negative lead and then after assuring ther were no flamibles present he would make contact with the positive lead on to the stuck bolt it would heat the bolt pretty much cherry red and break the corroded seal between it and the part it was connected to . I have used this method to free frozen bolts muself using battery power and on occasion a welder . It works like a charm you just have to be very careful about fire issues . Once its free your special socket may work. I hope this helps. Jeff
I think I'd prefer the arc welder instead of a wet cell battery outgassing hydrogen.
Thread Starter
Melting Slicks
Joined: Aug 2004
Posts: 3,078
Likes: 101
From: Riverhead New York
454 head bolt
OK! I did it! Wow! Am I ever HAPPY! Here's how! I took an acetylene welding torch and heated the bolt heads thinking to remove the hardness prior to drilling. While heating I realized I could shape the heads to an oval instead of round. (They where hex prior to rust, slipping sockets etc.). Then I took my Grabber sockets and pounded them on. Pushed down hard while applying pressure with a breaker bar. Talk about being Happy. I figure I've saved three days of extra work by not having to remove the heads. If you do not have a set of these sockets, get them. Worth thier weight in gold. Thanks to those who offered help. Al W.
