Page 1 of 1
#1 Cylinder head bolts
Posted: Fri Jan 30, 2009 1:49 pm
by RichardF
Hello All
I have about 6 cylinder head nuts that when unscrewed are unscrewing the cylinder head studs. Clearly they are stuck. I have tried a heat gun (maybe not long enough?) on the nut and also vice and molegrips on the stud shaft all to no avail. Any suggestions welcomed before I just go and buy 6 new cylinder studs.
Thanks in advance.
Richard
#2
Posted: Fri Jan 30, 2009 7:34 pm
by kingzetts
I had the same problem with 2 studs recently. I put the nut in the vice and used a heavy-duty stud extractor on the stud and they both came out pretty easily although I needed to use a pretty long handle on the socket on the extractor. The beauty of this type of extractor is the more you turn it the tighter it grips, so it will either get the stud out of the nut or snap the stud.
There was no damage to the studs in my case so I am re-using them, but to be fair head studs and nuts are not expensive and it would probably be cheaper to buy new ones than buy a heavy duty extractor if you can't borrow one.

#3
Posted: Fri Jan 30, 2009 7:41 pm
by RichardF
Thanks for that advice, I had resigned to the fact that it would probably cheaper to buy new studs.
#4
Posted: Sun Feb 01, 2009 11:44 am
by christopher storey
Richard : I don't really want to be a prophet of doom, but the domed nuts are likely to be the least of your troubles, assuming this to be a long stud ( 5 core plug ) engine . What happens is that as the studs unscrew, unless the block is absolutely dry , all sorts of liquid crud flows into the recess in the block into which the stud screws. The result is that when you try to screw the new stud in, you get a hydraulic lock, or if there is enough crap in there, a mechanical blockage as well
You may be lucky trying to suck /blow this out with a tube down the stud hole , but the best solution is to take the core plugs out and thoroughly clean out the stud recess . Even then you can experience a failure of the stud to seat, and I have sometimes had to mill a slot down the side of the stud thread, or grind the boss off the bottom, to get it to seat properly
#5
Posted: Mon Feb 02, 2009 3:23 pm
by RichardF
Hi Chris
Thanks for the info, I will indeed get a straw and try and suck out any crap.
Richard