That's an extremely comprehensive bit of I formation there. I definitely have my reading cut out for me. Thanks for posting this link. Posted from the TJJ App for iPhone & iPad
The bolts are only there to provide a clamp load. The clamp load is what prevents the engine and transmission from moving relative to each other. The bolts do not transfer the torque from the engine to the transmission. The moment the clamp load reduces, you'll shear the bolts. Long story short, it really doesn't matter what grade of fastener you use, as long as you can achieve the proper clamp load with them.
Dude, it happens, to all of us. I have lost track of the number of stuck/broken fasteners I have had to remove. You learned. Now you have a new skill. The day was not wasted.
Bingo. Grade eight bolts are stronger in tensile and shear strength than a grade five (or lower) bolt. They are still ductile, they are tough, not hard and brittle. Grade eight might be overkill here, but it won't hurt to use a higher grade bolt. A grade five will break at a lower torque if you bottom it in a blind hole.
i work on machines that are stainless steel and once in awhile somebody puts in a stainless bolt that ends up galling the threads and they break off the bolt. i have found using a dremel tool with small carbide bit to put slot in broken off bolt then a little heat with a screwdriver will usually get the broken part out. the process is slow as can be and i use this on regular steel bolts also.
No, they are not brittle, and may not be required, but perfectly acceptable to use. A little overkill never hurt anything in that kind of situation.
I just had a guy at work do the exact same thing. After he threw the water on it he worked it back and forth easily and got them out. It amazed me how that worked!
No argument on using a grade 8 for the bell housing....But..I believe that when Lakewood scatter shield bell housings first came around they included grade 5 bolts and a disclaimer or maybe NHRA rule not to use grade 8 because they would break too easily from a flywheel explosion.Anyone ever hear this?
Left hand drill bits and drill guides are almost always my first choice, not after it is all buggered up from other butchery. Some guys claim the welding on a nut trick works but I NEVER had that work, ever and then you have a mess. Any good hardware store should have left hand bits.
I did service work for while on some industial equipment. A guy I worked with there would remove a bolt that was broken off below flush by welding a piece of steel tubing to the end of the broken bolt. He stuck the welding rod down the inside of the tube while holding the tube in the hole against the end of the bolt. The tubing made the new "handle" for turning the bolt and protected the threads from the weld splatter, etc. Turned it out with a small pipe wrench. Worked like a charm for Charlie.
Thanks Greg for verifying this. You have to see it to believe it. Apparently the stud cools faster than the manifold, shrinking just enough to break loose.