I can't get a good socket fit on some of the badly rusted exhaust manifold bolts. Half came out easily with a breaker bar and 9/16" socket. On the remaining 3, the 9/16" socket spins, 1/2" socket is too small, 14mm is better but still too big while a 13mm is too small. They don't appear to be rounded out. I'd hate to pull the head, are there any other ideas of how to remove these bolts?
*Sitting here thinking about it, would heating the bolt with a propane torch increase the size of the head enough for the 14mm socket to grab ahold of it? I'll give it a try tomorrow.
I always go straight for a good condition name brand 14mm 6 point socket. Are you using 12 point or 6 point? 12 point will tend to strip off. If 14 6 point is too large and tends to strip off you may have to take a grinder or cutting wheel to cut a bit off the bolt head for a 13mm to fit.
I'm not sure heating the bolt head will make much difference in head size to the point it allows you to grip the hex head of the bolt better. Some say heat will help loosen the exhaust bolt thread grip, however, I've never had much luck since the point the bolt enters the cylinder head is quite deep inside the manifold and you really need it red to really make that much difference. If engine can be started, you would probably get as much heat as running the engine about 10 minutes and then tackling the bolts, since it will probably be 400 to 500 degrees around the exhaust manifold bolts.
For a bit more details on the way I remove them check out this post on the 63/64 Cadillac Site: http://6364cadillac.ning.com/profiles/blogs/removingexhaust
If you ended up needing some nice original bolts shoot me an email to jasonedge@nc.rr.com
Jason,
Excellent idea of slightly stripping down the bolt head to get a 13mm or 1/2" socket on it. Currently trying to use 6 point Craftsman sockets on this job.
I'll let you know how it goes.
Thanks,
I have no experience with welding so that's out of the question for me. I have a Lisle brand broken / damaged bolt extractor which works fantastic but I can't get in there to hammer it on to the bolt head. I might try the Craftsman kit you listed. For $25, it's worth a try. Thanks for the suggestion.
We're you able to get the bolts out? If so then what method did you use? I have to remove the exhaust manifold on my 66 Fleetwood 429 in the morning. So, any input in advance would be awesome. Also, has anyone seen Allen head exhaust manifold bolts on a Caddy? That is what is on my car and I am wondering if it is original or why someone would have used them. Please let me know.
Thanks,
Jason
The Craftsman extractor kit worked for one of the bolts. The other two that were stuck in there are in there good. I wound up biting the bullet and pulling the engine out and drilling them out. I'm going to take the heads in for a valve job / hardened seats too while it's out.
I can't imagine that the allen head bolts were anything proper.
If you have a feeling they are going to break the best bet then is to remove the heads of the bolts. You can grind them or burn them with a torch. Once you remove the manifold and still have a stud sticking out you can then get heat and pennatrant where it needs to be and you still have something to grab onto. Beats the heck out of drilling.
working on these exhaust bolts with the engine in the car is difficult, it can be easier to get to some bolts by removing the front wheel and inner fender. The extractor sockets may be too large in diameter to work. Good luck
The extractor that I used just fit over the bolt and tapered down with sharp teeth to bite into the bolt. The ones you hammer on definitely work better but are not an option with the lack of clearance available. The two remaining bolts were so corroded that they look like they were rounded out a long time ago, left in, and rusted over. What was left of the shoulders just came off when I attempted to break them loose, leaving nothing to bite on. There just wasn't enough there to handle the torque that was needed. Once the engine was out of the car and I had space, one bolt came out easy with the hammer-on type extractor. The other was so bad that I had to drill the head off the bolt. The manifold slipped off and I was able to remove the remaining stud with a little heat and vice grips.
Suffered the very same problem. I hammered a 13mm socket on (a real high quality) and that did the trick. However, I was doing a valve job and broke one of the bolts. I should have ground off the head of the bolt, as advised in this column. Then I would have had a stud to grab. No matter for a minimal fee the valve job included one exhaust bolt extraction (drilling and tapping).
Unbelievably I took off my exhaust manifolds on my '66 429 in less than 10 minutes tonight! I had this 429 as a spare engine (no AC car) sitting in my backyard for last 4 years with a plastic cover, then an old snowmobile trailer top over it. The engine was inside though from 1979 until 4 years ago, so I'm sure that helped, but surprised they came off so easy :D. Used a brand new 14mm 6-pt socket based on the tips here in forum...thanks Jason!
Planning on putting these on my '65 Eldorado tomorrow...are they the same (as '66 w/ no AC)? Looks like they are same. Looking up torque on these bolts now. Thanks, Chuck
Looks like they have the same part numbers. Check the attached:
Thanks Glen for confirming! I'll need to dig out my parts cd too :)