you know that sound you never want to hear, when you're torquing bolts down?

[stockgp]

you know, that snap sound that means one of two things. either you just snapped a bolt, or threads let go somewhere. well, i heard that sound just now.

 

i finally took my ass out to the garage to put my atop end back together, and started torquing the bolts to the lower intake.

 

got through the sequence to tighten the bolts to 15 foot pounds, and started to tighten them to 24 foot pounds as specified.

 

first bolt said *SNAP.* being lightly buzzed and pissed, i tried the next bolt in the sequence. same result. wgen i pulled the bolts out, the first had some of the threads from the head wrapped around it.

 

i'd hate to send my tgp to the junk yard, but that's about where i am right now.

 

i was even using an inch-pound torque wrench so i would guarantee myself not to over-torque the damn things. i used that same torque wrench to torque the rocker arm nuts.

 

i double checked my math to make sure i was using the right numbers. 180 inch pounds for the first round, then 288 inch pounds.

 

i'm pretty sure that i have absolutely no interest in using compromised heads. i'm not even sure i want to keep working on the damn car now. i have a whole other spare motor, but it needs some machine work. the crank may not be usable. i'm just very discouraged.

 

i know i'm not going to pull these heads off and take them to the machine shop. i'm really considering listing the car, spare motor and all the w body parts i have in the for sale section...

[Andrew]

easy outs and heli-coils man. It'll be better than new.

[stockgp]

the bolts aren't snapped off. just some of the threads stripped out of the heads. and i am definitely not taking the heads off to drill and helicoil them.

[virtuetovice]

Oh boy do I feel your pain. Just don't give up on it. Frankenstein the two motors together

[White93z34]

if you need a spare cylinder head let me know I might be able to help ya out there.

[GnatGoSplat]

Are you sure your torque wrench is in proper calibration? I did the same thing on a couple halfshaft bolts on my truck. The first one snapped, I thought it was a bad bolt, then the second one snapped, and I knew something was up. It turned out, the torque wrench had somehow magically lost its calibration and wasn't clicking until much higher than its set torque. I don't know exactly how far off, but bad enough to snap bolt heads off. Torque wrenches are usually long and heavy enough, it's really hard to tell by feel if the bolts are over-tightening. I switched to a different torque wrench and everything went fine. You might see if you can borrow or buy another inch-pounds wrench and see if yours is over-torquing before it clicks.

 

If not many threads came out, maybe you could just re-tap them and try again with new bolts and a new torque wrench.

 

I have trouble trusting cheap torque wrenches now. I wince every time I use mine, hoping it's still properly calibrated. I've been wondering if the digital ones are any more trustworthy.

[stockgp]

Chris, I may take you up on that even if I don't need it for this motor.

 

My spare motor hafd something wrong with the front head. Can't remember exactly. I think a bolt hole was stripped on that, too.

 

Shawn, I thought of that, too. I made the mistake of buying a cheapie ampro from advance auto.

 

The thing is, ibve only used it 5 or 6 times since I bought it. So now I don't want to go rent one from the parts store and have the same thing happenill post up a pic later of exactly how many thread coils came our

[GnatGoSplat]

One way you can check your torque wrench is to take your ft-lbs torque wrench and tighten a good size bolt (or a lugnut or something) to 24ft-lbs. Now see if your inch-lbs wrench set to 288 on that same bolt clicks, or wants to turn it more.

 

I just have trouble trusting those things after being burned before. Of course, what'd I do after I discovered my torque wrench was bad? I bought one for $10 from Harbor Freight.

[stockgp]

[19Cutlass94]

Ive got a 3100 Ill sell ya for a top swap

[stockgp]

nah. the whole idea of this car is to appear like i just bought it. straight from the factory look.

 

that means if i go ahead and keep working, i'll be using the same heads and intakes. albeit i do want to do some serious port and polish work.

[virtuetovice]

PLEASE keep going. If you scrap this TGP, the W body gods will kill a whole litter of kittens.

[Galaxie500XL]

While not ideal, it shouldn't be necessary to pull the heads in order to helicoil them for an LIMG...I did the same thing on my LQ1, and did the helicoil with the heads still installed. I just laid down tons of shop towels around the area, stuffed the intake passages nearby with paper towels, and then used a shop vac to pick up the pieces. Just cover what you can, and be paranoid looking for loose pieces, and you'll be fine.

[Mach 5]

Ive used time sert thread inserts which is a full thread sleeve. works well you can probably buy it online somewhere. That sucks though. I always thought intakes were 22 not 24.. I do first pass to 15 second to 22 the go over it at least 3 times to make sure its properly torque. these things are so finicky sometimes. I agree with that torque wrench idea with it being out of spec its a definite possibility

[White93z34]

what about tapping it out to a slightly bigger size?

[stockgp]

what about tapping it out to a slightly bigger size?

 

i don't know. they are already oddly sized bolts. it might be tough to find bolts the next size up in that length