New head bolt broke

[ORFORD2004]

I just bought head bolts from Vicks. They are hexagonal head instead of torx that was in original. When i torque the head with Mark 5 layers new gasket to 61 pounds-foot, the bolt #3 snap right on the thread parts flush with the base. I decided to reuse my original bolts and that time, it was #2 bolt that snap... Did anybody used stud instead of bolt? I pass a tap in the base just before installation and put some oil on the thread. My torque wrench is always kept with no tension on the spring. What do you suspect???? Bad torque wrench??? I will compare it tuesday with one from my machine shop.

[htchevyii]

I've had a few fiat head bots stretch, but haven't had any break yet. I'd definitely check the torque wrench.

[azruss]

running a tap just cleans the threads and puts all that crap in the bottom of the hole. make sure the holes are completely clean. might do a quick length comparison with new and old.

[ORFORD2004]

The tap was pass and i blew air in the hole making the coolant to splash.

[azruss]

watch where your hardware comes from. In my experience, the Chinese have yet to figure out how to harden something properly. most of their stuff is too brittle. they also use alot of recycled steel, so you really dont know whats in the mix. have run on to steel with some really hard stuff in the mix.

[ORFORD2004]

My torque wrench is from Canadian tire Maximum brand. It suppose to be the professionnal line from them. My friend have a snap on and i will compare them on a wheeel nut torque to 61 pound foot.

[ORFORD2004]

My torque wrench is accurate comparing to the snap on one. So i have a problem...

[djape1977]

chinese crap bolts sold as proper ones. i rather use old bolts than new ones since it's next to impossible to get good ones.
by the way, original bolts were hex head. not torx.

[ORFORD2004]

My bolts come from Vicks Autosports and i don't know where they buy them. The thing is that i'm stuck for another week and summer is short down here.

[djape1977]

only way to snap a head bolt is if it's low quality steel.
if your torque wrench was bad and bolts good, you could strip thread from the block if you were strong and smart as a mule.

no insult intended, i still believe that bolt is crap.

[obdulio39]

i've used the same bolts 3 times with no problem. get your money back!

[ORFORD2004]

I just send a e-mail to ARP Bolt. If they can supply me, i'll be in business . The bolts are made in USA. So pray for me so i can have a positive answer.

[ORFORD2004]

My head is on and torque properly. Thanks to ARP bolt. If you guys want to do the job right the first time, use the stud #ARP-AM5000-1LB and the nut #ARP-300-8344 from summitracing.com. I reuse the stock washer and everything is right.

[LIQUIDLOUNGE]

The players that remain in the US made fastener industry have been crazy busy, even through the recession...nobody wants to tarnish a hard earned reputation on a faulty nut, bolt or screw. How many of you guys have broken heads off of household type screws (i.e. drywall screws, wood screws, etc)? 10-15 yrs ago you may have stripped a head or two (usually with a worn bit) but never did the screw heads just snap off.

[djape1977]

made in P.R.C.