proper torque of head bolts

[Mermaidquest]

I'm not clear on what is meant by re-torque of the head-nuts after initial run-up. Do you break the nuts loose and start over or simply test the torque on the nuts as the are? Things have changed in 35 years!

[ndutton]

I don't think loosening before retorquing is intended. If it were I'm sure Don would have been specific about it in the MMI manual.

[Dave Neptune]

Mermaidquest, when retorquing do not loosen first!!!! The purpose of retorquing is just that of continuing to tighten as the gasket compresses over time. When torqueing a large flat area like a head it is important to tighten it sequentially and a bit at a time. In doing so you should notice that each time around you start the nut moving at less torque than you had tightened it with, that is the gasket compressing. After a few times of torqueing at "spec" and you get no more movement your done UNTIL YOU START THE ENGINE!!

Once you have run the engine and warmed it up it will need to be torqued again as the heat and pulsing of the cylinders firing will allow for further compression of the gasket. Keep the retorquing up until you get no movement. even if it takes a few warm and cool cycles. Then the head will stay put for a good long time. Mine has been on for over 30 years now since I had it off last.

The above is the single most important reason for having lubricated and good clean studs and nuts for this purpose. Dirty, rusty or sticky studs or nuts should be replaced for proper torqueing.

Note do not apply more than spec to see if you can get one to move, just go to spec repeatedly in order and with patience.

Happy Thanksgiving to all

Dave Neptune

[hanleyclifford]

As Neil once posted, "things that are more easily done are more likely to be accomplished", or words to that effect. With that in mind, and thinking about the A4 cylinder head, it is prudent to plan the lay out and routing of hoses and accessories on the top of the engine with as few impediments to the re torqueing as possible. It is important enough to requiring good access to the nuts that on occasion we might redirect or add fittings to achieve it. If you don't re torque, head trouble is bound to happen.

[Al Schober]

Agree, do not loosen - just tighten.
First engine job I did, used a torque wrench where you had to read the pointer against the scale. Not very convenient, but not much to go wrong with it.
Currently have two 'click' type wrenches in different ranges and they're very convenient - but I don't trust them and like to check them using the old beam type wrench (still have it). I wouldn't recommend buying a 'click' type wrench from Harbor Freight - savings aren't worth the potential cost of them being grossly wrong.