When To Re - Torque Head Nuts ?

[pgp001]

I am just about finished installing my new engine and planning a short test run later this evening.

My question is should I re torque the head nuts after the first short run, or wait until it has been on a longer run / runs and got everything good and hot a few times.
When they were new, I don't suppose it got done until the first service if it was lucky.

Phil

[philthehill]

Re-torque after the first heat cycle.
When new the Minor underwent a 500 mile service at the dealers who sold the car and which included the head studs being re-torqued.

[geoberni]

Back in the day, a head re-torque was a standard thing on the 1st service for all makes, typically 500miles or even less.
I brought a brand new Vauxhall Viva in '77 and I remember it was in the 1st service schedule at 500miles.
It sticks in my mind because I was in the RAF in Germany at the time, and it was a Forces Tax Free purchase that I collected in London.
I went out of my way to ensure I clocked up the 500miles in the UK while on leave, because my journey back to my station in Germany was going to be around 430 miles, and I wanted any niggles sorted before I took it in for a service at the GM/Opel dealer.

[JOWETTJAVELIN]

Yes as long as you observe it must be properly hot and then allowed to cool. So go and enjoy a drive.

[jagnut66]

Yes as long as you observe it must be properly hot and then allowed to cool

A point worth noting there, as previously I have tightened them down after the first good run to heat things up but may have not let it cool down fully again before re-torquing them.
As it happens I have been okay but I take it you mean that the engine should be allowed to fully cool down, before reaching for the torque wrench.
Best wishes,
Mike.

[oliver90owner]

Yes as long as you observe it must be properly hot and then allowed to cool. So go and enjoy a drive.

Nooo! Cast iron engines - retorque hot. Aluminium heads/engines - retorque cold.

First heat cycle (not taken out and run under load). This means allow to heat until the thermostat operates or, in the case of electric fan cooled engines, until the fan cuts in.

[jagnut66]

Nooo! Cast iron engines - retorque hot. Aluminium heads/engines - retorque cold.

That's why I was okay then.............
Good to clarify though.
Best wishes,
Mike.