Should I Replace My Head Bolts?

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BosnianLanos
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Should I Replace My Head Bolts?

Post by BosnianLanos »

I recently read that by design, the Lanos head bolts should be replaced any time they are loosened or removed. Is this true?

What harm could come if I ran the engine with the old head bolts for about 75 miles?
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Re: Should I Replace My Head Bolts?

Post by gse_turbo »

BosnianLanos wrote:I recently read that by design, the Lanos head bolts should be replaced any time they are loosened or removed. Is this true?

What harm could come if I ran the engine with the old head bolts for about 75 miles?
always, always, always!!! replace the bolts... they are designed to stretch one time. once you loosen them they are likely to all be different lengths, you will get uneven torque readings and a weak clamping force.

... all head and main bolts are designed this way, the only hardware that will return to original form is the ARP studs, they can be reused more than 10 times.

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Post by Pir0 »

How do the arp bolts return to the original form?

I thought they were stretch bolts too :/
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BosnianLanos
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Post by BosnianLanos »

Aww, shit! I suppose that's why my head gasket would leak after a couple of days of driving.

New head bolts it is.

Also, should I use some Loctite when installing the new bolts? And what color? Green, Red, Blue?

And what is the torque pattern for the bolts... The information I got is:

1st 18, 2nd turn 70 degrees, 3rd turn 70 degrees, 4th turn 30 degrees

Does this mean tighten all the bolts to 18 ft/lbs, then turn all the bolts 70 degrees, then 70 again, and then to finish turn all 30 degrees (Like a 4-step process?)

Does that sound right or is there other information?
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