Been trying to clean up the Mav and update some of the older pieces under the hood. In the process have encountered two stuborn bolts. I know there must be a method of removing them. I'm hoping to hear a suggestion before I do any more damage. The good thing is I finally identified the source of the minor oil leak that's been there longer than I've owned the car. One of the rear head cover bolts was broken off in the head. Is there a way to extract that? Do I drill it out and find a very long easy-out? I sure would love to seal the head and clean the engine off. More frusterating was my attempt to replace the thermostat. The exposed bolt on the driver side came out just fine. The other one just rounded it's self off right inside my 1/2" socket. I couldn't believe it. Tried getting a bite on it with some vice grips but my A/C systems makes it just about impossible to get anything BUT a socket on it. Do I really have to remove the entire A/C unit? There's gotta get a trick..... Hoping someone with more experience than me might lend a little advice. Thanks, Spyguy
Might try hitting the stubborn bolts with PB Blaster and let it soak for a while. Is the other a head bolt or a valve cover bolt? Also for the thermostat bolt you might try one of those wrenches that have all the needles in them that say they fit anything. I believe Craftsman has some sockets that fit over bolts that are rounded off. Someone else may know what they are called. Try some PB Blaster on the thermostat bolt also. Good luck.
oh, yeah......valve cover, that's what I meant. Might be time to open a door and vent this place out.
drill the valve cover bolt out of the head rail and use an easy out immediatley after using a product called CRC freeze off. as for the t-stat bolt.. use any decently designed screw extractor(I use a craftsman kit and it works well enough) with the same CRC freeze off as well. Should be able to just loosen the AC enough to get a bit better access or lay it to the side if need be.
This is the way I always take them out, although it can be a little time consuming; http://www.madelectrical.com/workshop/broken-bolts.shtml or for rounded off nut...........this is what I use and I bought them at Sears; http://www.sears.com/hanson-5-piece...13S3876689501P?prdNo=1&blockNo=1&blockType=G1
I've actually tried that a few times in the past too.. until I snapped the drill bit off inside the hole. What a disaster that turned out to be and me learned me lesson. Higher quality easy outs are much stronger and the larger the hole drilled in the broken bolt.. the better they work. Course.. a broken easy out is not much better than a broken drill bit either though.. so go easy with plenty of penetrating fluid. And that Irwin kit is identical to the craftsman kit I use and works well. Highly recomended tools to have waiting in your box if the need ever arises. Another old trick is to slot the head of the bolt with a cut off wheel or hacksaw and then use an impact screwdriver(http://www.harborfreight.com/impact-screwdriver-set-with-case-37530.html) after some penetrating fluid has had time to soak in and break free for easier extraction.
Wait! Stop! Think! All of the things above are good. But my advise is...spray first, let soak, drill, spray again, aply torch. spray again and pound in easy out. Get a grip Bro or this could get ugly. The penatrating oil doesnt always penatrate thats why I torch it and spray it again, it never fails on ball joints.
all good...plus after the oil sits I tap the head/top of the bolt and spray some more... and..." this could get ugly." quick...
I take it that you used a 12-point socket instead of a 6-point socket. If you didn't destroy the bolt head yet with the vise grips try a 6-point socket. You might need to tap the socket on the bolt head with a hammer since it's now distorted
Here's my advice: as for the valve cover bolt, there is no other option than welding a 5/16 nut over the broken bolt, filling the hole with weld, then just as it cools from orange to grey, unscrew the bolt. This method works 99% of the time. The Thermostat bolt? Try hammering a 12mm 6 point socket over the bolt head, then unscrew it. And in the future, never use more than a 1/4" socket and ratchet when installing valve cover bolts, and never use more torque than your wrist can deliver in tightening these bolts.
Check your valve cover bolts to see if they are too long and bottoming out in the hole. There's a good chance someone was using a bolt that was too long and it bottomed out. Then they broke it off trying to get it to pull the valve cover down and seal.
"hindsight is always 20/20", and BadDad's solution is good. I have always replaced "valve cover" bolts with screw-in studs..........that way you can't really over torque the nuts........but the 1/4" driver/socket is the way to go. I've had studs removed from some motors before that I just couldn't get out and when I was in Redding I lived close to a "Bolt removal guy", he did this for a living................on one that I had tried to get out for days he got it out in less than 10 minutes without using any heat or welding anything..........he used a pick and air pressure...............If I hadn't seen it with my own eyes I would have never believed it! Another time he used his EDM.......................than are many ways to "Skin a Cat".........IMHO
If you have a mig welder, or access to one, weld a washer to the vavle cover bolt. Then weld a nut to the washer. Should come right out. For the thermostate housing, I'd weld a nut to the top of the bolt. The heat will expand the bolt against the threads, then shrink back down. That action alone should let it come out.
Just for future use to everyone, Rust is a living organism. I was trying to tear down an old farming disc one time when I was young and full of energy. Used a lot of WD-40. I was having very little luck when an old freind came by and sat that disc in the pond. He told me he'd come by and show me a trick in a couple of days. When he came back and sat it out of the pond, I could nearly take every bolt out by hand. He explained that the rust came alive and softened up in the water. That caused all the nuts to loosen up. Great trick.
