While I have assembled numerous engines in the past, this is the second one where I’m using TTY head bolts instead of a stud, or an upgraded ARP head bolt. Out of all of the head bolts that I went through the process of 22ft lbs, then 90*, then 70*, ( 2013 5.3), One freakin bolt, the last one naturally, didn’t pull right. Even on the first 90* attempt, it was like it was already at full dead stop. This is a complete unassembled short block that has been in my possession that I pulled the heads off of, so it’s unlikely that there’s something in that hole blocking the bolt.

My question Is if I pull this one bolt off to ck it, I’m guessing that it’s a dead pup, and I’d have to get a freakin new bolt?

how do you get one new bolt?

 

Those with more knowledge will pipe in, but I'd suspect that since you never got to full torque on that one bolt that it should be able to be reused once you determine what the issue is. Are you sure there is no fluid or other debris in the bottom of that bolt hole?

 

You mean, you weren't able to do the first 90 degree turn on that second pass? (Then it technically hasn't yielded, in that case). Something is going on on the threads on the block, most likely.

A method that works well is to take a few of the old bolts, put them in a vise and cut a few slots along the bolt's longitudinal axis with a thin cut off wheel on the angle grinder. Use that as a poor man's thread chaser.

 

Most internet fasteners believed to be TTY aren't.

Before the lumbering herd of furious misinformasturbation about TTY fasteners, there were micrometers and men who used them to validate rod bolt stretch and bolt failure.

Just order from a free returns place, compare the length to a new one, and re-use as appropriate. While you're at it, measure the underhead bolt shank dia. to compare to the thread minor diameter. If it's not equal or smaller, it's not TTY.