head bolts torque

[craigieeb]

does anyone have the correct torque settings for the head bolts??


i think it's somthing like 22 foot pound then 90 degree turn then another 90 degree turn, but im not sure so can anyone tell me how close or how far off the scale i have went, i would appreciate it : )

cheers

[E30Adam]

Might help if you told us which engine.

[Brianmoooore]

Ther's an updated way of torquing head bolts that I saw somewhere recently. Wrote it down, but can't find it.

[craigieeb]

Might help if you told us which engine.

well both the 320i and the 325i, would be great
as the 320 is getting put back together after i blew it up with the nitrous, and the 2.5 engine isn't finished yet but i'll need the torque figures for when i bolt it all together dude : )

[Guest]

According to Bentley book of many words you are right i.e. for Torx head bolts it's 22ft/lb then 90 and 90 again.

[craigieeb]

cheer's 325tracky just what i was looking for m8


(is that the same for both engines??)

[E30Adam]

My Bentley manual says 30nm then 90 degrees twice

[craigieeb]

for what engine adam?

[E30Adam]

for what engine adam?

For the M20 engine. I've just fitted my head using the 30nm setting.

8nm isn't a great difference so it probably doesnt really matter, i always like to be spot on when it comes to cylinder heads though!!!

[craigieeb]

yeah same here m8, i'll set the ratchet to 30 then fella : )

cheers.

[Guest]

22ft/lb = 30nm

[craigieeb]

[E30Adam]

22ft/lb = 30nm

Ahhhhhhhhh

Smart Arse!

[Brianmoooore]

Half sure I read somewhere that this method has been superceeded by one that involves starting the engine in the middle of it, or backing off the bolts and retorqueing, or something.

[M3GTR]

That's for the older non-torx head bolts. The Bently lists both methods although BMW recommended replacing my hexagon headed bolts with the torx version when I once had a service with them (note just the once!) as apparently the hexagon headed bolts had a habit of breaking! All replacement head bolts I have ever bought for the M20 (and that's quite a few sets!) are always torx now.

[E30Adam]

That's for the older non-torx head bolts. The Bently lists both methods although BMW recommended replacing my hexagon headed bolts with the torx version when I once had a service with them (note just the once!) as apparently the hexagon headed bolts had a habit of breaking! All replacement head bolts I have ever bought for the M20 (and that's quite a few sets!) are always torx now.

Yeah all set's I've bought are torx too. I can't imagine starting the engine part way through, I do up the head bolts before sorting out the timing belt.

[Brianmoooore]

I'm not confusing this with the method of changing hex bolts one at a time. This is a newer method of torqueing up torx bolts.
Someone else must have seen it somewhere.

[Brianmoooore]

Found it! Was posted by temp18e30 on the old zone.
He said it was arevised system for tightening head bolts that he found on the TIS.
1/ Torque to 40NM

2/ Wait 15 minutes

3/ Torque to 65NM

4/ adjust valves

5/ warm up for 25 minutes

6/ Angle tighten 25 degrees.

Anyone know if this is a revised method, or a superceeded one from an old TIS?

[E30Adam]

Found it! Was posted by temp18e30 on the old zone.
He said it was arevised system for tightening head bolts that he found on the TIS.
1/ Torque to 40NM

2/ Wait 15 minutes

3/ Torque to 65NM

4/ adjust valves

5/ warm up for 25 minutes

6/ Angle tighten 25 degrees.

Anyone know if this is a revised method, or a superceeded one from an old TIS?

Sounds like a bit of agro doing it that way. Can you imagine a workshop having to waste 25 minutes warming the car up, I guess they'd be charging the customer for it but still, seems a bit odd.

If I'm fitting a new head, I always adjust the valves before I fit it too, makes it a little easier.