I broke a head bolt off in a smallblock chev. I was torquing them @ 65lbs. and got to the first bolt left side, and it just popped. I used steel head gaskets, and coated them with coppercoat for a good seal. I haven't fired it up yet. do you think it will leak ?
What was it that Clint Eastwood said: "Do ya feel lucky, Punk...well do ya?" THAT didn't turn-out well, either!
Would you rather retrace your steps now or take it ALL apart when that gasket starts to leak? Your choice.
The stud shouldn't have broke at 65ft lbs. With a conservative 145,000 psi tensile strength the safe torque range should be 70-93 ft/lbs. I would be curious to see what caused the stud to break. What does the yield point of the stud look like? You can narrow down the cause of failure by examining the yield point of the stud. http://www.croberts.com/bolt.htm Mike
uhhh, what fordrat31 said 2X, in other words it should not have broken....do you go to Vegas alot...... They were NEW bolts and you did CHASE the block threads before you started........didn't you......
Take it apart.. gonna be worse later with coolant in the oil and other atrocities going on. Either it was the wrong thread bolt or the threads were extremely dirty (or something in hole?). They are hard to break. I've used used bolts before, but they have got to be clean and the threads they go into have to be clean as well. Bob
With my luck it would leak. I'd be worried about the other bolts too. Were they used or new. If it was the first bolt in the sequence it is in the center of the head between two cylinders so it won't leak externally. You might be able to get the piece out with a long left hand drill bit without removing the head. Put a piece of tubing in the hole to help center the drill.
If he's as far as the head torquing stage, yank the heads and hopefully be able to extract the broken bolt... there may be enough sticking above the deck surface to grab. Then go over all the bolt holes with a tap to clean them out. Bob
and dont BREAK THE TAP OFF theres some slight obstructions when getting in a bit to the end of the threads
That's where experience comes in... gotta know when to quit before the tap takes a bite... and bites back. Use a light machine oil, take your time and keep cleaning the crap off the tap. Bob
It's cast iron and cast iron has enough natural lubricating properties that you tap it dry. And if you're using a bottom tap, be very, very careful. Trying to get that last quarter turn can cost you much grief! Dave
Hell, go down to Home Depot and get an "easy out" kit. Drill a hole in what's left of the bolt, hammer the tool in, and turn it LEFT...........
The tap is used to clean out the bolt holes AFTER the bolt is fished out. Which is a whole 'nother saga to get the remnants of the bolt out. Bob
The discussion involving a tap is about cleaning out the head bolt holes in the block AFTER the broken bolt is removed. Dave
I don't understand.. First bolt? I would not keep on going with the others. I would lift the head off and get it out. The gasket will still be good. Most of the above posts agree.
If the gaskets haven't been compressed, I'd re-use them. I would have to see first hand what's going on to make a real decision though. Bob