engine and drivetrain Cylinder Head bolts, to reuse or not to reuse...

[burndog]

There are a lot of conflicting arguments about the reuse or replacement of cylinder head bolts out there. I have never read anyone on the forum mention this in all of the head replacement posts. Is it overkill to replaceme them or simply always the standard procedure?

 

Also, I once saw the head bolt torque specs and tightening pattern / procedure diagram on the forum. I can no longer find it.  Anyone have it or point me in the right direction to it?

 

Thanks in advance,

 

BURNDOG

[Preyupy]

The M10 did not use "torque to yield" bolts.  Unless you are building a very high compression ratio race engine( >12.5:1) and are planning on torqueing the head beyond the factory spec of 55ft/lb there is no reason to replace the stock bolts unless they show signs of damage to the threads or are very rusty. 

[OriginalOwner]

I just had my engine rebuilt and new head bolts were installed, the charge was $27.00.  For something that inexpensive, no reason to re-use old bolts.

     (EDIT BASED ON NEW INFO:  $27.00 was invoiced for 1 bolt).

 

do a Google search on  "1975 bmw 2002 head bolt tightening" .... then click on "IMAGES"   ...... you'll see a whole bunch of pictures and such.  Find the right one.

 

Cheers,

 

Carl

Edited January 20, 2015 by OriginalOwner

[Rustpile]

There is only one good reason to re-use head bolts, and that is having trouble getting new ones. They are cheap, and seem available from a lot of places in the US(like IE). 

[burndog]

Original, where did you buy a complete head bolt kit for $27.00? 

[Hans]

BMAparts. Under $20. I figured what the hell, cheap insurance. I have, however, recycled a few sets with no probs.

[jgerock]

Even Autohaus AZ has head bolts for the M10. I think that is where I got them for the tii in 2009.  Cheap insurance when building an engine or replacing a head gasket - especially if the engine is unknown to you.  Follow the instructions included with the head gasket for tightening.

[OriginalOwner]

burn,

 

$27.00 is what the invoice says .....

SO, I just looked again ..... OOPS ..... it says Quantity 1,  $27.00 ......

I just modified my post above to reflect this new info.

 

I'll be having a conversation with my rebuilder about this .....

 

Cheers,

 

Carl

Edited January 20, 2015 by OriginalOwner

[71bmr02]

Penske has them listed for 4.29 ea.

[TobyB]

Oh, hell, here comes the RANT:

 

Buying new head bolts is a waste of money.

 

And given the quality of fasteners in the aftermarket parts chain, they may not be half as good as what you have now.

The BLOCK will fail at about the same time a head bolt gives up.

 

If they're rusty, bent, damaged or are currently on fire, buy new ones.

 

Otherwise, spend the money on beer.

 

And yes, this has come up before, but it's been a while...

 

never bought a new head bolt for an M10 in his life,

t

[KFunk]

To add to paranoia:  I bought new headbolts for the heck of it, cuz why not, they're cheap.

I managed to snap a brand new OEM headbolt while tightening it down.  I had to pull head back off, drill it with cobalt drill bit, and extract it (straight flute extractor).  Not fun at all.  

Are the recent manufacturers of the bolts crap, which led to this result?  Who knows.  I bought ARP studs next instead.    

Edited January 20, 2015 by KFunk

[kbmb02]

Like Toby and KFunk, I lean towards re-using bolts which I 'know' to be good (that story above about a new one snapping supports this approach). However, unlike Toby, I spend the money on bourbon. -KB

[burndog]

Mmmmmmmmm, bourbon.

[roadhog0]

Reused mine with no problems. Put new ones on this motor build. I'd reuse them again.

[Buckeye]

IMHO this is excellent document. First topic on the link below. It is Pdf file.

http://www.bmw2002faq.com/index.php?s=9c5e110919987bf90cf1a30173d0eeb0&app=googlecse#gsc.tab=0&gsc.q=cylinder%20head%20oil%20leak&gsc.page=1