# Head Bolt Torque - question



## redone17 (Aug 17, 2011)

We are in the midst of swapping in a ported G60 head onto my 88 Fox Wagon and the SABÓ Head Gasket had some interesting torque spec information (I will take a picture of the cardboard insert that came with the gasket when I get home tonight - hoping it didn't go out in the trash today). ziddey and I had a question regarding re-torquing.

_Anyone have any input on re-torquing head bolts? The directions it came with said to re-torque after initial warmup, and then again after some miles. I've heard of people doing this, but thought it was technically against the mantra of TTY bolts? The Bentley makes no mention of re-torquing, and neither did any of the brands of head gaskets I've used in the past. That said, I've reused head bolts many times before and never had a case of a "stretched" one, so I'm sure it'd be "fine." I'm curious what WaterWheels and others on the 8v forum would say about this..._ - ziddey

This is a Brazilian made gasket - unfortunately I didn't take any photos of it - but it seemed to be great quality.

I am 99% certain it is the same one that is in this (stolen) pic:









Any input would be appreciated.


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## WaterWheels (Aug 14, 2005)

Don't re-torque. I would bet the gasket set is kind of a "covers many years" item, I can see at least one seal you will not use, and the instruction sound to be for old watercooled 4 cylinder engines. If you have the type of head bolts that are round with a twelve point socket in the head, they are not retorqued. The old hex head bolts were torqued then re-torqued later. An 88 should be the newer style head bolts and not hex head ones.


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## ps2375 (Aug 13, 2003)

If you have tty bolts, I would not re-torque.


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## redone17 (Aug 17, 2011)

Thanks for the quick response guys! 

Finishing this up tomorrow. Looking forward to the increased power/torque of this head and 270 cam. The WOT switch should be a nice addition as well :thumbup:


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## ziddey (Apr 16, 2006)

Yessss. That was what I was expecting you guys to say. I'm finally right for once . I'm curious why the initial torque specs call for two 90° turns instead of exact torque figures. Isn't that normally to "stretch" the bolts?


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## ps2375 (Aug 13, 2003)

Yes, you torque them to a known tq, then you add the two 90* turns and that put the bolt into it's "stretch" and gives the amount of clamping force that someone somewhere deemed is needed.


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## ziddey (Apr 16, 2006)

Right. Which is why I'm curious why the head gasket's instructions say to torque to 6.5kg-m, two 1/4 turns, and then retorque to 12.5kg-m after warmup and break-in. Seems with regular bolts, it'd just have torque settings and no "turns"?


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## ps2375 (Aug 13, 2003)

no idea. could be a translation thing or just plain wrong.


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## redone17 (Aug 17, 2011)

this was the old gasket - anyone weary of those markings in red?:


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## WaterWheels (Aug 14, 2005)

The two red circles look to be “burn through” areas between cylinders. Often this is a result of either the engine being overheated or the torque on the cylinder head was not correct. When the engine gets overheated the expansion between the block, cast steel, and the cylinder head, cast aluminum, is different enough that it squeezes the head gasket. When the engine cools again the gasket does not return to fill the gap and hot exhaust gasses can begin to force through the small gap. The same happens if the torque holding the head down was not correct or equal around the bolts. It would have to be a “gross” error or broken bolt or dirty threads or some other factor which allows the torque to be too little. I kind of think the overheating is the case here as it is not in just one place.

I can’t see any problem in the green circle. If you do see something then maybe explain what it is or do a close-up picture to show it. In any case you should have the mounting surface skimmed to be sure it is flat and fix any burns it might have.


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## redone17 (Aug 17, 2011)

Green circle was meant to show that one was a-ok. 

I noticed when removing the bolts a few were definitely easier to break - so, maybe your inclination is right. 

The head I'm swapping on was tested and has a flat mating surface. From what we could tell the cast iron looked smooth and flat as well. I'll take a closer look to the stock head later today and post some pics. 

As for overheating - I've owned the car for the last 3 years - and haven't had that problem while I've had it - but who knows the 22 years before that. Engine has just above 80k on it. I'll have a better indication on overall temps once I have the VDO gauges installed. 

Having installed these head bolts myself - it's nice to have some confidence in knowing it was done right. 

Thanks for all your input. I need to spend more time in these parts :beer:


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## redone17 (Aug 17, 2011)

Torque specs:









Dark marks on head - but no warping or divots - seems straight/flat.


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## ps2375 (Aug 13, 2003)

I have never seen VW torque specs like that. I don't think I have ever used a Sabo HG, either.


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## WaterWheels (Aug 14, 2005)

You might not be able to see or even feel with a finger any erosion, but I would bet there is a little. Remember you have super-hot gasses forcing through a tiny space so some erosion has to take place. But at this point it really is not important as you are installing a different head.

The drawing on the spec sheet is of an older style head gasket. It seems to be a South American company too. Could be they mixed up the two ways of installing the head or just plain old got it wrong or something. Go by the manual, torque to 60nm (I believe) then 180 degrees more. Both can be done in steps, i.e. 40 – 60 – 90 degrees – 90 degrees. Be sure the holes are clean and you use a small coating of engine oil on the bolts. I have a tap which I brushed for a long time on a wire wheel to dull which I use to clean-up the block threads (so no material is removed).


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