1988 DL Wagon Intake Manifold Seized

I recently embarked on a project to replace the head gaskets on my 1988 Subaru DL wagon and the two tall bolts on each side of the intake
manifold broke when I tried to remove them. Now that I have all the bolt heads off the intake manifold it appears that the remaining bolt shafts have corroded to the extent that the manifold is not moving when I try and lever it off the block. I am afraid to use too much force for fear of breaking it.
Has anyone run into this problem before? Any suggestions? Is not worth the efforts?
Thanks
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Been there myself a couple of times. What worked for me was carefully drilling out the broken bolts. Don't drill into the cylinder heads but just down to the heads.
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Thanks very much...Once I drill them out should I get the remainder of the bolts drilled out and the heads re-tapped for installation?
johninKY wrote:

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No. Once the intake manifold is removed...and you can get fairly violent with it in the removal process because you really can't damage anything...use a lefthanded drill bit slightly smaller than the broken bolts and drill down through the center. Most of the time the broken bolt will unscrew itseld before you drill completely through it. Good idea to center punch the broken bolts and first drill a small pilot hole. Also good idea to soak the bolts with something like Power Blaster for a day or two before drilling. Don't get carried away with drilling to deep into the heads. Check some of the bolts you were able to remove to determine how deep you have to drill. Go to deep into the heads and you will ruin them.
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In fact, spray the bolts at least half an hour before you center punch them. Can't hurt, and the impact of punching may break some bonds and let the penetrant get into the gaps.
Also, don't use WD-40 instead of a good penetrant. It isn't a good substitute.
Mike
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On 2006-03-20 15:45:25 -0800, "Michael Pardee"

and if you are miraculously lucky enough to get the seized bolts out, remember to use anti-seize compound on the new ones !!!
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But they stay in *so much better* if you don't! <8^P
Mike
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