# Re-use Head bolts



## FastLapRSII (Jul 15, 2001)

I've heard that there are stretch bolts on non-stretch. Supposedly one has captive washers and one does not. The guy at my machine shop said I can re-use them up to 3 times. I've never heard that before. I have the 12-point head bolts with captive washers.


----------



## Gunsup (Jan 8, 2002)

*Re: Re-use Head bolts (FastLapRSII)*

Hmmm, I've alwyas been told not to reuse head bolts and I don't. They aren't that expensive and too important to take the risk.


----------



## tkic (Dec 18, 2001)

*Re: Re-use Head bolts (FastLapRSII)*

i also have heard both sides, but the more convincing people tell me to replace the studs. i dont see how they could stretch more than once.


----------



## someonehasthenameiwant (Feb 8, 2001)

*Re: Re-use Head bolts (FastLapRSII)*

Use new studs it will let you sleep better.


----------



## ABA Scirocco (May 30, 2001)

*Re: Re-use Head bolts (FastLapRSII)*

I asked the same question about a month ago, here's the responses I got http://forums.vwvortex.com/zerothread?id=191742


----------



## OhioBenz (Dec 6, 2001)

*Re: Re-use Head bolts (ABA Scirocco)*

NO


----------



## wyn1984gti (Oct 24, 2003)

*Re: Re-use Head bolts (OhioBenz)*

hum let me see.... NO!


----------



## eurotrashrabbit (Oct 25, 2001)

*Re: Re-use Head bolts (FastLapRSII)*

3 words ARP HEAD STUDS


----------



## ncvwnut (Jun 5, 2000)

Yes you can.....


----------



## eurowner (Jan 26, 2002)

You can reuse the 6 point head bolts as they are not stretch bolts. 
If it has 12 points, you can not reuse them.
Buy them new and be safe, buy ARP and know that you've got the best.


----------



## no.og.a2 (Nov 30, 2004)

*Re: (eurowner)*

dont do it.


----------



## antichristonwheels (Jun 14, 2001)

*Re: Re-use Head bolts (FastLapRSII)*

I have reused them without issue. torque to 65 ftlbs


----------



## no.og.a2 (Nov 30, 2004)

*Re: Re-use Head bolts (antichristonwheels)*


_Quote, originally posted by *antichristonwheels* »_I have reused them without issue. torque to 65 ftlbs

you can but its not always a good idea. and why not replace them while you have the head apart


----------



## SignOfZeta (Apr 17, 2003)

*Re: Re-use Head bolts (FastLapRSII)*

It certainly would be nice to have a definite answer to this common question...
Here is what I know. There are torque-to-yield head bolts, and standard heardbolts. A torque-to-yield (stretch) is certainly one use only. Never, ever, more than one use in any application.
However, the head has been off my GTI three times with no problems whatsoever, and yeah I redline it several times a day. They are the twelve pointed heads. My Bently (for an 85, my car is actually an 86) makes no note whatsoever regarding replacing the headbolts. This would lead me to think they are reusuable since the only other advice to the contrary is from people on this forum who just paid quad price for headbolts. (That's a lot of money for a sticker on the back window, IMO). If you are turboing the thing or something, go ARP, but IMO the money is better spent elsewhere on the car.
The only thing that puzzles me is the actual torque spec, which is:
first pass: 40Nm
then 60Nm
then one additional half-turn.
Torqing to an angle is usually something that goes along with torque to yield bolts.
Aiside from that I don't see anything indicating they should be thrown away. My friend who is a 2nd generation VW mechanic in a shop that has been there for 30 years re-uses them also, but then he has been known to cut corners.


----------



## ncvwnut (Jun 5, 2000)

*Re: Re-use Head bolts (SignOfZeta)*


_Quote, originally posted by *SignOfZeta* »_
The only thing that puzzles me is the actual torque spec, which is:
first pass: 40Nm
then 60Nm
then one additional half-turn.
Torqing to an angle is usually something that goes along with torque to yield bolts.
Aiside from that I don't see anything indicating they should be thrown away. My friend who is a 2nd generation VW mechanic in a shop that has been there for 30 years re-uses them also, but then he has been known to cut corners.

One thing is that stretch bolts refer to the fact that they expand/contract with the heat to keep the same torque. If they didn't you would strip the bolts everytime you try to take them out. 
The reason for having that spec is because you are torque stepping. that gives you a better overall seal. My ex brother-in-law, who is a mechanic, 20+yrs experience reuses them with no problem and that is on high end BMWs and Mercedes too.


----------



## machschnelGTI (Jun 28, 2004)

*Re: Re-use Head bolts (ncvwnut)*

"Stretch bolts" is not really the correct term. "Torque to yield" is the correct term. All bolts stretch, thats how they stay tight. Torque to yield bolts are designed to stretch more. Generally, Torque to yield bolts have cut down shanks whereas the VW headbolts have full diameter shanks. I have reused them with no problems. If the bolt is no longer capable of maintaining the proper torque, you will feel it in the torque wrench as you tighten them. The bolts should feel like they are getting continually tighter as you turn them. Occasionally you will feel the wrench "slip" like the bolt is just turning and not getting harder to turn. In this case, the bolt needs to be replaced. If everything feels normal during tightening, they are still usable.


----------



## SignOfZeta (Apr 17, 2003)

*Re: Re-use Head bolts (ncvwnut)*


_Quote, originally posted by *ncvwnut* »_
One thing is that stretch bolts refer to the fact that they expand/contract with the heat to keep the same torque. If they didn't you would strip the bolts everytime you try to take them out. 

A stretch bolt, or a torque to yield bolt is called so because when you tighten it you stretch it. It will never snap back, and stretching it again will mess it up so bad that any spec you try to put on it will be useless.


----------



## pfcs1 (Jun 7, 2003)

torque to yield bolts (all 12 point VW head bolts) are called strech because they do-and just like an elastic band, when steched, they return to length (pretty much-more about that later). I have always re-used them at least 3-4 times befor replacing them (usually with used ones from a virgin motor). The factory manual tells yiou to always replace them. TTY hardware is designed (ever wonder why the threads come so far up the shank?) to strech, and the installation procedure tightens them into the elastic region of their material. If they (or any ohter threaded hardware for that matter) are tightened much beyond the elastic region, they enter the plastic region, where they are permanently deformed/stretched. Decreasing turning torque is a hallmark of this, and that sinking feeling the experienced wrench turner knows, signalling that it must come apart again-if you turn it more, it's just gonna break, and if you don't replace it, it'll fail later. Some mkanuals give a specification fot TTY bolts: when the length under the head exceeds the spec, it's garbage. I've re-used TTY rod bolts too, but I'm a little more reluctant to find out how many cycles they're good for-the consequences ar a lot more severe! Phil


----------



## blacked out gti (Aug 7, 2002)

*Re: (pfcs1)*

I buy my head studs for about $1 each. That is only $10. I could not see why someone would spend 5 or 10 times that much for the same thing, unless they take their engine apart a lot. Some people also like to use copper head gaskets and reuse those.


----------



## blacked out gti (Aug 7, 2002)

*Re: (blacked out gti)*

This website has some great pricing for reusable head bolts:
http://www.qualityvwparts.com/hrdwr.html


----------



## SignOfZeta (Apr 17, 2003)

*Re: (pfcs1)*


_Quote, originally posted by *pfcs1* »_torque to yield bolts (all 12 point VW head bolts) are called strech because they do-and just like an elastic band, when steched, they return to length (pretty much-more about that later). I have always re-used them at least 3-4 times befor replacing them (usually with used ones from a virgin motor). The factory manual tells yiou to always replace them. Phil

Well, here's what I know. Every service manual I've ever seen for any make has said to replace a torque to yield bolt every time. In college I was told the reason for this was the exact nature of elasticity obtained at the point of yield (the spec torque) can only really be obtained once. They don't "snap back", or at least not enough according to anything I've read. This has been the case with VWs, and well as lesser cars, such as stuff from GM, where they are using torque to yield bolts in rods, and even to mount the wheel bearing assemblies.
The factory service manual does not say to always replace the 12 pointed headbolts on my GTI . It just doesn't. I have the factory service manual right here, in my hand, and it doesn't say that. I'm not saying that they shouldn't be replaced, I'm just saying that VW didn't tell me if that is the case, and so I tend to think they aren't torque to yield, so I've never replaced them.
I guess in the end this doesn't matter. It seems many people have re-used the headbolts on these engines without problems. Also some people have had problems, but to be honest there are about 20 ways to jank up a headgasket job, so I'm not sure that means anything. I've got about 30k miles on my current one, many of them hard, and the motor is something like 220,000-250,000 miles old. Not sure exactly since the odometer broke years ago.
In short, it only matters if you are the sort that wants to spend $25 a piece on headbolts and are looking for justification.


----------



## Issam Abed (Feb 12, 2004)

*Re: (ncvwnut)*


_Quote, originally posted by *ncvwnut* »_Yes you can.....

What he said.My dealer didnt have head studs and I re-used mine on a NA 8V Golf.Just torque them @65ft/lbs and you will be fine.If your really considered about them then just spend the $36 or whatever they cost @ your local dealer.


----------



## ABA Scirocco (May 30, 2001)

*Re: (Wizard-of-OD)*

FWIW, my local dealership says they reuse the head bolts on the cars they service and I've looked through both of my Bentleys and they don't stay anything on this subject.


----------



## Aurora_GL (Aug 10, 2004)

*Re: (ABA Scirocco)*

i have re-used my head bolts, but ive had issues with them . i just found autotechparts.com head bolts are uber cheap less then $.70 each. and thats cheap enough to get new ones, head gaskets are only $14 there too. i did my entire head including vavle seals and guides for less then $50 and thats really good, there all german made parts and are good quality.


----------



## mechsoldier (Aug 14, 2004)

*Re: (blacked out gti)*


_Quote, originally posted by *blacked out gti* »_I could not see why someone would spend 5 or 10 times that much for the same thing, unless they take their engine apart a lot. 

Are you referring to ARP?


----------



## blacked out gti (Aug 7, 2002)

*Re: (mechsoldier)*


_Quote, originally posted by *mechsoldier* »_
Are you referring to ARP? 

Yes.


----------



## mechsoldier (Aug 14, 2004)

*Re: (blacked out gti)*

They aren't the same thing, ARP headstuds offer better clamping force. For all motor what your saying is true, but for forced induction.....
A stud is better than a bolt


----------



## Peter Tong (Jun 17, 1999)

*Re: (blacked out gti)*


_Quote, originally posted by *blacked out gti* »_I buy my head studs for about $1 each. That is only $10. I could not see why someone would spend 5 or 10 times that much for the same thing, unless they take their engine apart a lot.

I went with ARP for many reasons, but the main overriding reason is an intangible that I call "peace of mind under boost"







Same went for the rod bolts...


----------



## G60orbust (Dec 14, 2004)

*Re: (eurowner)*


_Quote, originally posted by *eurowner* »_You can reuse the 6 point head bolts as they are not stretch bolts. 
If it has 12 points, you can not reuse them.
Buy them new and be safe, buy ARP and know that you've got the best.

correct minus the last part...
the 12 pt bolts stretch once... then they don't stretch anymore
they have to be treated like non-stretch bolts and re torqued after 500 mi.
SO
spend $32 on 2 valve cover gasket sets and use the old ones
or do it once and buy new bolts and only spend $18 on the vcg ?


----------



## The_Hamster (Jul 31, 2000)

*Re: (G60orbust)*

The bentley for mk2 says replace diesel and 16v specifically but no mention of 8v iirc.


_Modified by The_Hamster at 3:04 PM 2-23-2007_


----------



## MK2SnowPilot (Sep 8, 2005)

*Re: (The_Hamster)*

damn this thread is old!


----------



## G60orbust (Dec 14, 2004)

*Re: (MK2SnowPilot)*

so am I!!!


----------



## MK2SnowPilot (Sep 8, 2005)

*Re: (G60orbust)*

Not as old as me


----------

