Ok, I was removing a head yesterday and came across a stuck head bolt that put a halt to this very quickly (removing them in order of course and can go no further).

I tried using an impact wrench (not the most powerful one out there mind you, it's the $75 Craftsman model) and I also tried doing to loosen it by hand but got no where. This baby is just plain stuck!! Can anyone out there provide some tips on loosening it?

Try a break over bar. That worked for me

Originally posted by texasz

........... Can anyone out there provide some tips on loosening it?

Long handled breaker bar, with an extension on handle to gain leverage. Also, BE CAREFUL so as to not snap the bolt in half. Apply pressure smoothly, a little at a time.

When I had one that was stubborn, I'd take a 1 or 2lb hammer and give it a couple whacks on the head of the bolt, sometimes the shock will help break em loose. Used this trick on many stubborn head bolts on old Cummins diesels.

Then it's either a breaker bar, or a stronger impact......

Dont force it,get a bigger hammer.

Combine both methods. Apply smooth tension on breaker bar (3 ft tube hadded to strongest handle you have. Half incher should be good) and get friend to hit over top of allen bolt (thru the handle etc). I would use a plain swivel handle (cheaper) rather than a ratchet handle. If you don't have one get one with a replacement gaurantee (you may break it!!!!).

Ok, so you all know how you are working on something and things are not going well you just can not see the forrest for the trees....well that was me on this problem. I have used the breaker bar technique before but had just got so frustrated I forgot about it. :stupid:

I tried that this morning and it worked great!! Thank you all for reminding me about this method.

Ok, I tried all of the above and the last head bolt refuses to come loose. It unscrewed for a few turns and now it won't budge either direction. I have drowned it with liquid wrench, put steady pressure on it trying to get it to go either direction and it just plain refuses. Any other ideas out there?

If you have an oxy torch, try heating up the head of the bolt.

Since it loosened a couple turns and then seized back up, here's my take on it. I suspect a slight head gasket leak which allowed a bit of coolant to get to that seized bolt. The bolt now has a thick ring of corrosion or mineral deposits on the shaft just above the threads. As you try to remove the bolt the thick ring on the shaft is too large to go through the hole in the head, and that is where the bolt is stuck. Sounds unlikely, but I have personally experienced this very same thing on an L24.

Options? There are only two that I can think of. If you can get to it (depending on which bolt it is), cut the head off the bolt. Then you will be able to lift the head off, and I think you'll find the the headless bolt will be easily removed.

If the bolt is one of the ones where you can't get to it to cut the head off, you're going to have to use your breaker bar with an additional extension for more leverage (a pipe slipped over the end works well) and reef on it until the bolt breaks. (This is what I had to do on mine.) In this case, have all the other bolts loose so that no warping pressure is applied to the head itself. If my suspicion about the thick build-up on the bolt is correct, the bolt will break somewhere between the head of the bolt and the build-up on the shaft. Then you can lift the head off the block. And again, I suspect the remnant of the bolt will easily unthread once it is broken.

Don't use a pipe, try to get a lend of a torque multiplier so that if the bolt breaks you won't end up on the garage floor holding a broken wrist

Another thought - you may be able to break the head of the bolt off by using a drill and some high quality bits.