M20 exhaust stud replacement

[mark_i]

i just removed the M20B25 exhaust manifold and 7 of the 12 studs came out of the head.

What is the recommendation to remove the copper nut and return the studs without damaging threads or the head...

Thanks in advance

[mark_i]

just did a zone search... 3 pages of stufff going back to 2006...

looks like the plan is to by replacement studs and copper nuts.

[Brianmoooore]

Unless they are 'as new', I'd remove the other five studs and bin them all along with the nuts.
If they are suitable for reuse, then run a thread cleaning nut (or die) along the thread you can see, drop them in WD40 for a day, screw two ordinary nuts onto the thread that should be in the head, use two spanners to lock them against each other, then, holding the inner of the two nuts with a spanner, unscrew the copper nut from the other end.
Use the same 'two nut' method to remove the remaining studs from the head.

[mark_i]

thanks Brian

for peace of mind, i'll buy a set of new studs and nuts. the exposed stud threads look and feel corroded.

[clipper]

Make very, very sure that the new studs are fully wound into the head before torquing up the manifold.

Sounds like basic information, but I had one stud that didn´t wind right in for some reason and when I torqued the maifold it pulled the stud out of the head

[mark_i]

thanks for the advice... with the new studs i will double check they are fully wound into the head before mounting the exhaust manifold.