I've got three very badly stuck bolts holding my engine to transmission housing. Penetrating oil (as usual) hasn't made any difference, I've warmed things up with a torch... obviously can't go crazy here... have rapped 'em with a hammer... what's next? Others are loose.
What are the details? Is it a hard to access location? Is the socket not staying on the bolt, or is the breaker bar not long enough? Any signs of corrosion?
Access is easy, corrosion is pretty bad (New England car). Two are on the bottom of the housing, one on the back that's a little harder to get to. No issues with the socket / head interface. Threads are seized horribly and these bolts are not as strong as one would like. The good news is that the one I broke won't be too tough to drill, but I'd sure like not to have to drill three of the bastards if it can be avoided. I'm using a 1/2" breaker bar and a 6 point impact socket.
And that right there is the magic of the "seized fastener removal kits" sold by Lisle, Thexton, etc. They work with an air hammer, so they apply lots of fast blows straight down on the head of the bolt, but they do not apply excessive force to twist the bolt. You just use your own wrench by hand to keep a steady reasonable turning force on the tool, while it shakes the fastener loose without breaking it.
I try heat or cycling back and forth from hot to cold whatever I can do to get that sucker out You got to be careful going into aluminum SM-A715F ?
Learn somethin' new every day (thanks!). I found the Lisle kit on Amazon. Cool idea. Won't solve my problem because it won't go where I need it to. My current inclination is to use a "tempilstick" indicator and a torch to heat things up. I don't have any useful experience with aluminum castings like this, so I just wasn't willing to hit it with enough heat (for obvious reasons). Is 650 F enough? Hell if I know for sure. edit: the liquid products may be easier to work with I have a pretty good high temp IR thermometer too... I have not tried on aluminum, but if I smut it up with the acetylene torch it should probably get a good reading...
Seems like you just want to heat cycle the material make it expand and contract and expand and then on the last expansion as soon as it starts to cool try to back it out see what happens and then maybe the cool or quench some kroil or something like that SM-A715F ?
No need for a temp stick. Rub bar soap like Ivory in that areal At 500 degrees F., it will turn brown. That's the limit you want to heat aluminum before it softens. It's an old technique to de-temper and soften aluminum and to keep it from cracking from the old airplane barnstorming days.