Mohammed

I'm changing the lifters in a '02 ws6 ... is it fine to reuse the head bolts or get new bolts ?

CRAZZ28

iTrader: (13)

Buy new ones. The stock bolts are torque to yield bolts and are not reusable.

69RS

iTrader: (1)

Why are you pulling the heads to change lifters ?

O2Form

I would reuse them, lots of shops and dealers do. As long as the engine was never overheated regardless of what anyone tries to tell you the bolts are fine. Overheated bolts will stretch and be useless.

Alot of others are going to chime in and say NOWAY........

I would be alot more concerned about the threads in the block. I would buy a thread chasing tool, NOT A TAP but a tool made just for cleaning and chasing those threads. Your life will be so much easier if you do trust me I NEVER LIE.

People seriously if the bolts were not reuseable because they were weak from being TTY then they wouldn't be holding in the 1st place.


Case in point ALL the bolts in brake systems are TTY but everyone uses them over and i've NEVER seen any fail. This headbolt thing is such BS its insane. Its a way to empty pockets of money. Tell you what send me the money you were gonna use for new bolts if you wanna waste money. I'll guarantee you won't have any trouble and you will feel better cause you spent money.

99LSS1

iTrader: (12)

You have to pull the Heads on an LS motor to swap the lifters.. DO NOT re-use GM head bolts.. They are TTY, And need to be replaced. You can get them for around 40 bucks or you can buy ARP and these can be re-used!!!

O2Form

If your engine was never overheated and you buy the proper thread chasing tool and use it properly, cleaning the threads etc.I will guarantee the old bolts will work and i'm so sure they will I"LL pay for your repairs if any reused bolts fail.

PSSST tell ya what to do to test that the old bolts are ok to reuse, take a new bolt and measure it. Then torque to yield then remove it and remeasure it...........then you will believe.

1quickirocz

Ive compared a new head bolt vs a used headbolt and the stretch is VERY noticable......i would NEVER use a TTY head bolt EVER and none of these engines they came out of were ever overheated. OP save yourself some headaches and replace them or get some ARPs.

and by the way the reason for TTY bolts on a cylinder head or any engine component for that matter is because the torque is more evenly distributed across the head causing less deformation. but i guess when comparing a new to old and the bolt is literally 3/16" longer than a new one its ok to reuse??????? hmmmm dont know about that.

O2Form

So tell me how you compared them? Sorry i don't believe you, I bet you don't even know how to check them.

1quickirocz

sorry you dont believe me thats your feelings. but anyways i thought i put it very simple in the last post but if not ill make it more clear. if you remove an OLD bolt and hold it next to a NEW bolt the OLD bolt is noticably longer and has less diameter at the top of the bolt just under the head than the NEW bolt. therefore the OLD bolt has stretched as it is designed to do. If you reuse the bolt and torque it to the proper ft lb spec and THEN tighten it to the proper angle its going to do what???? STRETCH ALOT MORE.....MORE THAN ITS DESIGNED TO DO. We take appart atleast 5 or 6 5.3s with piston problems a week at my dealership and we look at things like bolts when we do this. It was just last week when we compared a new to old bolt. No doubt it will probobly work to reuse once but I would never do it and I dont recomend it to anyone to do. Well unless you want to take the chance of it breaking. But your probobly smarter than the engineers that design this stuff.........oh wait its a money thing I forgot......

LS1-450

iTrader: (33)

WTF, to the people arguing against replacing. It's a no brainer. When you pull the heads the stock bolts need to be replaced. As noted previously, they are torque to yield. Better yet, replace 'em w/ ARP head bolts. The ARP bolts can be re-used & are stronger than the stock bolts.

Randy WS6

iTrader: (69)

The stock bolt are TTY, You can buy the stock replacement bolts at any local part store for around $20.00 a set, Is it worth breaking a head bolt in the block for $20.00.

BlueMagicSS

iTrader: (4)

IMO replace them for peace of mind.

chevymec

iTrader: (19)

GM says to replace them for a reason, they designed the motor.

JohnLoose

I like the old saying, "You can do it cheap or you can do it right!" Buy the new bolts!

BIGSRTURBO

iTrader: (2)

Yea I would deff replace with arp and be done with head bolts FOREVER!!!!!

O2Form

You still didn't tell me how you check them, honestly i'm not busting your ***** but there is NO good reason not to reuse them EXCEPT gm makes money on new bolts and the rare case they are stretched too far from heat.

Randy WS6

iTrader: (69)

Here and article on TTY bolts , This should explain why no to reuse the head bolts
http://www.enginebuildermag.com/Arti...uetoangle.aspx

O2Form

A well-respected OE engineer specializing in engines tells me that critical fasteners have about six rundowns in their useful life. They use four of those at the OE manufacturing operations, leaving rebuilders just two. One rundown for checking sizes puts us on the last rundown during final assembly. My thinking is: why take the chance? Replace the fasteners! The relative cost compared to the total engine job is small and the peace of mind is high.

OK that article ADMITS each bolt can be used 6 YES SIX TIMES!!!!!!!!!!!!!!

DOn't let GM BS you dummies!

If gm said you all need to jump would you ask how high?


Those head bolts are no different than any other head bolt. So get off it!

KCS

iTrader: (20)

The difference between GM's TTY head bolts and others (like ARP) is that the others are not stretched to their yield point.

The engineer said a fastener has about 6 rundowns, but the implication is that the bolt has not been stretched beyond the yield at any point during or in between those rundowns. With the fastener stretched to it's yield, assuming it was accurately torqued in the first place, it still wouldn't take much to stretch beyond the yield and to reduce the clamping force when you do go to reuse them.

Other head bolts, like the ARP's, are torqued to roughly 75% of their yield, so even if overheated, they're much less likely to be stretched beyond their yield than a OEM bolt. The OEM bolts just do not have that margin of safety that the other bolts do.

A corporation like GM has a staff of engineers and millions upon millions of dollars to invest in researching things of this very nature. If you think we're dummies for taking the recommendations of a corporation like that for it's own products rather than someone on the internet with poor grammar (that's you), then you may need to take a look in the mirror. We're not the ones putting our engines at risk over a $40 set of bolts...

O2Form

I got news for you...If you think GM spends the time to TTY the head bolts at the factory you're nuts! They use the standard torque air tools just like they did for 30 years.

Please guys don't fall all this bs people post up that someone else told them!

I got other news for you...if the bolts were actually over torqued in the 1st place THEY WOULDN"T HOLD!

I'm done discussing this you do as you please...BAAA BAAA