Exhaust manifold stud torque setting

[Goforit]

Hi folks

I'm new here and I've just done the head gasket on my 1.4 twin cam 207.

As expected the exhaust manifold stud nuts didn't undo so the studs came out. I've removed the nuts from the studs and cleaned them up but I'm unsure what torque setting to use for replacing the bare studs.... I've searched many forums but there seems no consistent answer.

Does anyone here have any idea?

Thanks

David.

[CitroJim]

For the earlier and quite similar TU version of your engine David, the torque is quoted as 25 Nm or 18 lbf ft (foot pounds)..

So I'd be happy to go with that for yours...

Recheck them after a thousand or so miles after the gasket has bedded...

[Goforit]

Hi Jim.

Thanks for the reply, I got the torque setting for the nut from Haynes, I'm trying to establish how tight I should put the bare stud in prior to mounting the manifold.
Some suggest it should be just beyond finger tight, some suggest the same as the nut going on it...

[MattBLancs]

Thinking about what is going on (stud bottoming out in the tapped hole or shouldered/unthreaded section of stud meeting the top of the head's threaded hole) I'd think no advantage in either case to torquing this down.

As such finger tight sounds fine to me.

Obviously taken to extremes, if the head threads are completely clogged with muck/poorly formed/rusty studs/etc and this were to prevent the stud from screwing into the head fully, then adding a nut (and in this hypothetical scenario, stud threads at the other end and the nut are both perfect and free running) then is risk of an only partially engaged stud stripping the one or two threads it did engage with from the head.

So obviously, have a look / measure studs and confirm is screwed in well if following my "finger tight" suggestion.

Matt

[Goforit]

Thanks for that Matt,

Thankfully the female threads in the head are perfect and spotless, as are the studs.

[MattBLancs]

Excellent, well in that case all is well, finger tight should be spot on.

I'd probably put some copper grease on them (but generally have somewhat of a compulsion to apply that stuff often anyway!)

I recently learnt of the difference between copper nuts and just "copper flashed". On an EW10 engine I had the exhaust manifold off am sure the original nuts were just copper (as weren't magnetic) I've just bought some new ones but found in arrival in the post found they are only plated (or "flashed") mild steel.

Matt