Author Topic: head torque (Read 3371 times)

Isamemon · « **on:** January 30, 2009, 02:16:54 PM »

book I have says for a 91 318 with a M42 is ( in steps) to torque the head bolts to 22-25 lbs, step 2 turn 90-95 degress, step 3 90-95 degrees
is this correct or has this been updated
doing this saturday

KenC · « **Reply #1 on:** January 30, 2009, 03:29:51 PM »

That's correct. Make sure you have the correct torquing pattern as well. And hold the wrench position for a few seconds after you tighten them.

papercutout · « **Reply #2 on:** January 30, 2009, 05:46:42 PM »

Having just done mine any being 100 miles into the 500 before we check it again, is there any tightening to be done, just to re-torque the head at 500ish miles?

I'd like to be safe, and the printout results of tightening procedure didn't mention it!

Thanks.

Isamemon · « **Reply #3 on:** January 30, 2009, 09:29:19 PM »

I was also PM'd that between each stage to let it sit for 10 minutes :confused:

papercutout · « **Reply #4 on:** January 31, 2009, 05:05:31 AM »

That 10 mins is the time it takes you to reposition yourself round the engine bay

(doing it with a friend is a lot easier btw)
In reality, I have no idea if leaving it makes a difference, so don't ask me, we just did it.

nomad · « **Reply #5 on:** January 31, 2009, 08:43:53 AM »

It is a torque bolt that stretches a certain amount when you get that pressure on it.
There is no real torque number so you can't "retorque" after a while. What would you do to make sure it is tight? Can't do another 90* you know what I mean?

I waited a little while in between stages, I also soaked my head bolts in motor oil as the book says so that they turn smoothly to the torque point. I had one that apparently didn't have enough oil on it and it chattered a bit at the final 90*. Kinda scared me but i decided not to take all of them out and redo. It go to the correct point.

The only thing i did was cheat by not buying the dial gauge/protractor, I used my finger since the angle is an easy one to remember. Yeah, ghetto like that...

papercutout · « **Reply #6 on:** February 05, 2009, 02:33:54 PM »

Is that the answer then, they don't get re-tightened at 500 miles or so? Makes life easier, but kinda feels wrong!

KenC · « **Reply #7 on:** February 05, 2009, 06:23:00 PM »

They're expansion bolts. Don't retighten them.

nomad · « **Reply #8 on:** February 05, 2009, 07:14:11 PM »

yep, that's the answer