robertbartsch

I was sucked into buying new head bolts from GM. The parts manager told me, however, that his mechanics have done lots of Gen III work and they never change bolts. He claims they never have problems and that GM's position on replacing the head bolts is a money-grabbing ploy to sell the public new bolts they do not need.

Your thoughts?

CHRISPY

The guy you talked to is full of ****. you NEED to replace the headbolts unless you throw studs in.
Cheers,
Chris

Fulton 1

iTrader: (9)

The bolts are torque-to-yield, which means that tightening them to the specified torque will actually stretch the bolt past the material's yield point. This results in plastic deformation preventing the material from returning to its as-formed shape after the load is removed. Any future torque values applied to this bolt will be unreliable since the metal has been deformed.

So, as Chris pointed out, the guy is full of ****.

<small>[ September 10, 2002, 05:21 PM: Message edited by: Fulton 1 ]</small>

Raughammer

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fulton 1:
<strong>
So, as Chris pointed out, the guy is full of ****.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">.....DITTO.
You HAVE to replace them.
We ARE taling about the M-11 head bolts and not the small M-8 bolts, correct?

The M-8's are reusable. The M-11's are NOT.

wrencher

iTrader: (2)

I'm a gm tech and I'm say <img border="0" alt="[bullshit]" title="" src="graemlins/gr_bs.gif" /> I bet the warranty people would like to know if their half-assin' jobs & maybe billing the bolts it's <img border="0" alt="[bullshit]" title="" src="graemlins/gr_bs.gif" /> All dealers are independant franchises you found one to avoid.

PK 01somWS6

hmmm...All I ever hear is that you MUST replace the head bolts....Well I never have, my current set-up right now has had the head bolts in and out 3 times, all torqued to spec w/ zero problems..I also know others who have done countless head swaps w/ zero problems..but maybe I'm just lucky...oh well...go ahead and get new ones to avoid being paranoid..

99MONGOOSE

This crap makes me laugh. When I added ported heads and a cam it cost me about $2600 just for the heads/cam, why the hell wouldn't I buy new bolts! What is that extra $$$$ gonna break you? If it is then you shouldn't be modding ANY car!!! Thats not as bad as re-using old oil, which I have heard of, but re-using old bolts is in the same book if you know what I mean.

Fulton 1

iTrader: (9)

I ran into the same thing with the brakes on my C4. The caliper frame to spindle mounting bolts are torque-to-yield (166 ft-lbs). When I did my brakes I went down to the local dealer to grab four bolts and they didn't even stock them! What's more they told me that nobody in the area had them in stock and they'd have to be special ordered. All of this even though the Helms manual clearly states that they are torque-to-yield and must be replaced. <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" />

ynneK

Classic Chevrolet of Morristown NJ reused my headbolts. 10,000 miles later, and across the country I noticed I had a coolant leak that I could not trace.. Brough it to Carr Chev of Beaverton, OR (great dealership) and they fixed my car up.. Reported that the headbolts were reused and that caused my heads to loosen and slowly leak coolant!!!!!