nvrstsfd23

I replaced the bolt after the cam swap but now we have to take it out. will I need to buy a new one or is the one I have ok since it was only used for a day.

SideStep

You will have to replace it if it is a factory GM crank bolt, it has stretched... Don't risk it.... Heck they are only $7-10....

lsx24

iTrader: (45)

Hmm don't make a mistake, the required bolt is relatively low cost and can be replaced when removing the pulley.

Red99TA

iTrader: (11)

The bolt is designed to stretch when you put that final 120 degree turn on it when tightening down. As a result once it's removed you need a new one. They're called torque to yield bolts b/c you're taking the bolt to it's yield point and it has permanent plastic deformation after that (it's stretched).

redbandit98

iTrader: (13)

while on the subject whos got the best deal on an arp? hell this buying a new bolt (for the 4th time i think) is getting expensive....i always say ok this is the last time its coming apart then..6 months later its down again.hahahh

ss rally red

iTrader: (8)

I dont know how much the ARP bolt is but make sure you have a 12 point socket when you install it........

by the way my cost on the GM bolt is 2.76.

conan

iTrader: (5)

I got my arp bolt from thunder about 25$$ .

ChucksZ06

iTrader: (9)

I personally believe replacing the bolt is a load of crap. The bolt may not be as elastic as it was but who cares...it sure isn't going to break. Put a dap of silicone on the treads and under the washer and it will never come off until you want it to. It is not like it is a head bolt that has really been stretched.

rush7

iTrader: (2)

my opinion: replace the bolt with an ARP and be done with it. it is a quality piece of metal.

technical

Torque to yield is just that...yield(point of failure/stretch)
It doesn't matter what type or size of bolt it is...TTY fasteners are only "good" for one use.(torque-ing) Even non TTY fasteners are only good for a limited number of torque-ings.


Just the facts ma'am.

digitalsolo

iTrader: (24)

I'm just curious of anyone who has installed a used bolt properly and had a failure? I've reused TTY bolts on rockers, and crank several times (pulling rockers on and off on my L67 car, probably 5 installs on the bolts, 45K miles, no failures). Just relube them, and you're good to go, if you install them right.

...that or spend 3 bucks. That's what I did for my new balancer bolt.

DONAIMIAN

iTrader: (18)

ive heard of people not buying a new one without having any failures, would I do it, if I was in a bind yea, but if I was in no hurry id just get a new one.

chpmnsws6

iTrader: (70)

my buddy re-used his factory bolt and had the pulley fly off while the car was at 6800rpm

Red99TA

iTrader: (11)

Was there any evidence of the bolt breaking or was it completely gone (like it just backed out)?

chpmnsws6

iTrader: (70)

it had backed out.

he put that bolt on TIGHT to... 200+ pound man lifting himself up by the breaker bar

2xLS1

iTrader: (25)

200+ pound man lifting himself up by the breaker bar doesn't mean it was tq'd to 37 ft lbs then turned another 140* though.

technical

The correct install is to replace the bolt. If they're going to break they typically they will break during torque-ing. Otherwise you just don't get the correct tension and they either back out like the above post stated or they don't provide the correct seal... e.g. a head gasket.

chpmnsws6

iTrader: (70)

can't really do much more then that

2xLS1

iTrader: (25)

Then be prepared to keep losing bolts. With a long enough cheater bar, the bolt can be turned 140* easily. I use a 3/4" drive breaker bar with a 3' piece of pipe. I actually have to be careful not to go past 140*. I use the Kent Moore F/W locking tool also. On over 25 cam installs, I've never had a crank bolt come loose.

Tally TransAm

iTrader: (17)

agreed

i weigh 125#'s and even i can get it to 140