Cylinder head stud spinning!

[Shug1e]

When reinstalling my cylinderhead and tightning all of the bolts to the correct torque setting, one of the four raised studs came loose stripping the thread in the lower engine casing. Due to a valve guide coming loose and climbing the valve stem, i have had to remove my cylinderhead again, a bit of frustrating bad luck! . Does anybody know if there is a way to fix the stripped thread as it still locks in position but does not hold tight enough when torquing the cylinderhead back in place and Is this stud vital since it is not a major oilway to the head?. cheers Shuggie

[emjay]

I'd drill it out and either tap it for a larger bolt or install a heli-coil for the original bolt.

[tfb]

All the studs are vital, whether they include the oilways or not. You must fix it; a Helicoil kit will do the job.

[Shug1e]

Cylinder head stud spinning!

Hello all, was going to take your advice and install a helicoil in the base of the engine block only to find the origional thread holder has split in half so there is nothing to hold the helicoil in place!.. The origional problem was cylinder #4 was burning oil, so was #3 a bit, so i thought maybe a couple of valve seals had come loose or i had damaged piston rings. The valves, guides, seals, barrels, rings turned out to be ok. The spinning stud is out of the 12, is a tall stud close to you, first right from centre. Does anybody know if the slight lack of torque on the right side of the engine would cause a slight leak in barrel#3 and a more major leak in #4 and is there a fix for the base of the stud without removing the engine? cheers Shugie:?

[Suzuki mad]

Any stud not torqued down will allow the head to weap and cause low compression. Depends where it is as to what cylinders it will affect.

If the stud hole has split then your course of action is to strip the whole engine down and take the case to a very good aluminium welder who can build the hole up with weld. Then file it back to to shape to match the original case. After that get it drilled and tapped and all will be right.

Others will suggest another material such as 'metal weld' but its no avaliable in the UK as I know.

Had my crankcase welded up after PO sheared two case bolts off.

Suzuki mad.

[Shug1e]

Cylinder head stud spinning

"your course of action is to strip the whole engine down" ?. Are you called "Suzuki Mad" for a reason?

[Suzuki mad]

YEP!!!!


Started on a A100 via GS425,GS550,GS1000E, GSX1100ESD,GP100U,GSF1200You might think I like Suzuki's.

You could lug the whole bottom half of the engine to a repairers, but save up for a hernia operation before hand.

As I suggested earlier, others may have a less destructive way fo repairing the broken stud hole.

Full removal is my perfered way as i have come to learn that 'bodge jobs' never really last.

Suzuki mad

[SqDancerLynn1]

A competent heliarc ?? welder should be able to fix it without complete dissasembly. cover everything with wet ragsI would bet the stud was overtightened without the correct headbolt Nut/washers