Head gasket leak prevention - Retorque headbolts?

[volvolugnut]

Since our Volvo white block engines seem to be inclined to have head gasket leaks at some point, would it be helpful to retorque the head bolts as preventative maintenance?
Head bolts and gasket materials can relax over time and heat cycles. A bolt torque check at high mileage might delay or prevent a leak.
Your thoughts and ideas? Benefits? Risks?
volvolugnut

[dikidera]

No idea about that, but I gave them a good 150 degrees on the last step. Take that head gasket.

And yes, they are prone to blowing, much to the surprise to a lot of people. As for why it happens, unsure. I wonder if detonation also plays a role. My 2.4i engine routinely pulls 7-13 degrees from the base map timing due to possibly knocking, even with a mix of 95 and 100 octane for some mid-grade fuel(100 octane being 93-94 american)

[abscate]

Torque on these is huge. 60 Nm plus 130 degrees angle is probably a 300 Nm torque

I wouldn’t mess with that.

I did tighten Shaggs and eliminated an oil leak but I also won the lottery twice.

[jonesg]

differential expansion and contraction through heat cycles might be causing scrubbing due to co-efficient between the head and the block.
so i wouldnt presume the head bolts are coming loose, the gasket is probably damaged from scrubbing.
i drive it like it was designed and i'll fix it when needed.

[MoVolvos]

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A long long time ago I had re-torqued 3 cars if my memory serves me right. 87 Integra 160K, 90 Galant 99K and 88 Camry Wagon 240K in that order. All had oil leaks from the head gaskets and no coolant issue. I start by loosening in factory sequence an 1/8 to 1/4 of turn then re-tightening to factory specs in factory sequence. You always have a chance of a broken bolt but the leaks were substantial enough in my mind so had nothing to lose or it's a head gasket repair. Reduce leaks enough to let is go and I think the 88 Camry was successful.
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[BlackBart]

Are our head bolts stretch to torque? Meaning one-time use, no re-torquing?

[abscate]

Are our head bolts stretch to torque? Meaning one-time use, no re-torquing?

Volvo does not say they are single use. GuruJ here says he will re-use them, once.

[dikidera]

I always replace. I got grade 10.9 bolts, and on the final torque sequence I gave them a good turn with my degree wheel.

[volvolugnut]

I always replace. I got grade 10.9 bolts, and on the final torque sequence I gave them a good turn with my degree wheel.

So, one good turn deserves another??
volvolugnutr

[MoVolvos]

I always replace. I got grade 10.9 bolts, and on the final torque sequence I gave them a good turn with my degree wheel.

So, one good turn deserves another??
volvolugnutr

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At some point there's no turning back just free 360 in either direction.
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