Rustmonger
Member
I have been tearing into a c169 in a 300 utility. It was sold to me as having a "busted block".
The first thing I did was yank the head and get it (the cylinder head) into a trusted machine shop.
No cracks or breaks.
The engine has three (yes, really)different types of pistons in it, and while the top of the block was really ugly, I couldn't discern an obvious leak trail. All of the sleeves are ruined, so no problem, just keep diving until you touch bottom,...
I started pulling studs in prep for removal of the engine and a total investigation. Each stud NOT into the water jacket was no issue, but when I got to the studs that were into the water jacket, I hit a brick wall.
Here is what I have tried, each episode separated by a abundant dosing of penetrating oil, all using doubled head nuts to apply torque;
*Saturate the top area around stud with Penetrating oil then tap with a hammer on the top nut downwards to try to make oil penetrate.
*Saturate the top area around stud with Penetrating oil then hit with an air chisel on the top nut downwards to try to make oil penetrate.
*Saturate the top area around stud with Penetrating oil then hit with an air chisel sideways close to the block to try to make oil penetrate.
*Heat block
*Heat block a lot
*Heat block a truly frightening amount
*Heat stud mildly (probably 800 degrees)
*Heat stud cherry red
So far I have broken two studs. To my utter amazement, the broken studs were dead soft in the center and hard as a file out at the perimeter. I can get a high quality 1/4" drill bit to go in, but a 5/16" is immediately dulled. This provoked me to try to soften (anneal) the broken off studs, but I have been unable to soften them, even with a direct application of a torch.
What in the world did they make a head stud out of 1956 that would fight back like this?
I fancy myself a very experienced mechanic, and I now feel like the gauntlet has been thrown at my feet.
My vertical mill has almost exactly enough space under the head to be able to machine out the broken studs with a solid carbide end mill after I drill a center hole, but I sure don't want any more practice than absolutely necessary. Any comments or suggestions welcome, or if you just want to laugh at my expense, well that's okay too.
Jeff
The first thing I did was yank the head and get it (the cylinder head) into a trusted machine shop.
No cracks or breaks.
The engine has three (yes, really)different types of pistons in it, and while the top of the block was really ugly, I couldn't discern an obvious leak trail. All of the sleeves are ruined, so no problem, just keep diving until you touch bottom,...
I started pulling studs in prep for removal of the engine and a total investigation. Each stud NOT into the water jacket was no issue, but when I got to the studs that were into the water jacket, I hit a brick wall.
Here is what I have tried, each episode separated by a abundant dosing of penetrating oil, all using doubled head nuts to apply torque;
*Saturate the top area around stud with Penetrating oil then tap with a hammer on the top nut downwards to try to make oil penetrate.
*Saturate the top area around stud with Penetrating oil then hit with an air chisel on the top nut downwards to try to make oil penetrate.
*Saturate the top area around stud with Penetrating oil then hit with an air chisel sideways close to the block to try to make oil penetrate.
*Heat block
*Heat block a lot
*Heat block a truly frightening amount
*Heat stud mildly (probably 800 degrees)
*Heat stud cherry red
So far I have broken two studs. To my utter amazement, the broken studs were dead soft in the center and hard as a file out at the perimeter. I can get a high quality 1/4" drill bit to go in, but a 5/16" is immediately dulled. This provoked me to try to soften (anneal) the broken off studs, but I have been unable to soften them, even with a direct application of a torch.
What in the world did they make a head stud out of 1956 that would fight back like this?
I fancy myself a very experienced mechanic, and I now feel like the gauntlet has been thrown at my feet.
My vertical mill has almost exactly enough space under the head to be able to machine out the broken studs with a solid carbide end mill after I drill a center hole, but I sure don't want any more practice than absolutely necessary. Any comments or suggestions welcome, or if you just want to laugh at my expense, well that's okay too.
Jeff
