Hi everybody,

I had to replace my toast head gasket and now I am wondering if I can use my bolts again. They all came off easily and the threads are undamaged.
Not that I am stingy in the wrong place, I simply can't get them in time, here in Germany. The car sits in a friend's shop since two weeks now, and I am running out of time.

Any recommendations for
- checking them, like measuring the strain?
- pretreat them, besides oiling them?
- a readjusted torque?

Thanks for you help

 

Just re-oil them and torque them to spec.

 

What I can tell you is that back in the early 1960's (the last time I rebuilt an engine), no thought whatsoever was given to needing new head bolts. The originals were used and worked just fine.

So, bottom line is the should work without problems for you.

 

In your situation if they are in great shape I would reuse them. If there is any rust on the shank or threads don't gamble with them.

 

I always re-use head bolts even on race engines, although I have not gone over 10.6 to one compression. Clean them, and oil the threads and under the heads. Let the excess oil drain off.

 

^^^^

What he said

wire wheel the external threads of the boltstuds as needed.

 

Newer engines use torque-to-yield head bolts, which stretch when installed and thus cannot be used. Older engines (including every Olds V8) did not use this type of bolt and they can be reused just fine - assuming they were not overtorqued at some point.

 

I always run a tap through each hole and give a blast of compressed air and then wire wheel the back side of the hex and threads. Then use a little spray grease on the back side of the hex and threads and torque to specs.

Pat

 

Thank you all for the quick answers!

 

Always good practice to chase the threads in every bolt hole when rebuilding a motor. The CSM specifies motor oil as the lubricant for head bolts. The torque values are based on this.

 

If I am reusing bolts I put in to begin with I have no problems doing it, also it depends on compression.
I dont like re using something some idiot could have impacted in before me.

 

I have re-used head bolts on diesel engines with over 400 PSI of compression and had no issues! I also measure them for stretch before in stalling.

Pat

 

I wouldn't reuse pitted headbolts. If the shanks or heads are pitted, find some different ones. usually not a problem for running motors or ones stored inside. Its those "its been under a tarp in the yard for three years" motors I would worry about.

John

 

Really? Are there folks that install head bolts with an impact? No particular order then also I would guess. Wow.



I wouldn't reuse pitted headbolts. If the shanks or heads are pitted, find some different ones. usually not a problem for running motors or ones stored inside. Its those "its been under a tarp in the yard for three years" motors I would worry about.
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Bolts like this will either come to torque nicely and hold properly, or not. Minor pits, or those not between the threads and the head seat are of no consequence. Almost every factory head/ main bolt I have ever reused has performed perfectly. After 2 or 3 tightenings, you get a good feel for the torque vs amount turned relationship. Torque rises and rises steadily until your wrench goes "click" - or your reading is satisfactory, on the bending beam type TW.

The one failure I can think of was when assembling a 330, I forgot that it was not a BB, and tried to torque the #1-4 mains to 120 lb-ft like the SB #5 and BB all mains... SNAP. Doh! Oh yeah #1-4 go to -80- on the SB. I discarded all the front bolts and started over. The good news is the broken part comes right out when threads are clean and oily.

If the fastener torque rises, then fails to rise with more turning, that indicates a stretched or otherwise failed fastener [thread pulling, etc.]. Usually right after the flat spot with no torque increase comes the "snap"... but it isn't your TW, it's the fastener snapping. For example, look at the "high strength steel" main stud that came with the CAT brand POS main girdle which I am ridiculing here:

http://www.ebay.com/itm/150646769737...84.m1555.l2649

It behaved as described above. good, good, oh damn soft, softer, SNAP, at less than 80 ft-lbs. Chinesium pc of crap. Seller HOTRODBIKER. Avoid.