Stuck Cam Cap bolt

Regarding the torque values - the Kawasaki Service Manual states "All of the values are for use with dry solvent-cleaned threads." If the threads or fasteners have oil or other liquid on them all bets are off. Ed

if you go with an 8mm replacement, use a button head bolt so you have clearance for the cover.

The main reason the bolts are stripped in the head is overtorquing the bolts

Our process is to cover the cam closest to the cap being tightened with a clean folded shop towel for cushioning, then use the heel of a palm to press down hard on the cam while at the same time tightening the cam cap bolts. That removes much of the load from the threads. Two people make that part of the job easier; one to press, the other to run the ratchet. Once snug, tighten to spec.

Thank you very much men. It's this kind of specialized knowledge sharing that made me a $ supporter of this site.

Now, when I bought this the seller had had the top end freshly done on it. But to me it was too noisy. Evidently the mechanic who did the work blew out the threads on two of the 4 cam cap bolts and tried to shortcut his way out the damage. The noise in the top was loudest right there. But that guy would have had to have been a member of this site to tap into others experience to avoid what happened, because you won't find this kinda chit in the book.

And, although I'm not a Professional Thread Repairer, I do play one on television....

Seriously though, I've repaired wayyy more damaged threads and broken bolts in 40 years than I expected or wanted too. And I find I still have more to learn.

Good stuff here guys. Thanks again.

Another big cause of stripped bolt holes is sealant in valve cover holes or oil in cam cap holes. The sealant or liquid won't compress, but also will not feel solid. It will feel squishy, so you will think you need to apply more torque. But the threads will just strip out very easily. I use a pick and whatever else I can to get every last thing out of the bolt holes.

Pulling down the cams into position using the threads puts a lot of stress on the aluminum threads. Using vice grips and clamping the cams down into the bearings before installing the caps saves the day although it's difficult if not impossible on some bikes for the intake cams. Regarding stripped threads, I'd use helicoils. Timeserts are better for things like spark plug threads but helicoils are a good option for cam caps.

Just my cents worth here, rather than go to inserts go for a stepped stud system 8x1.25mm down to 6mm, i done this to all sixteen on a head 14 years ago and it is still running around, it also allows you to keep the locating dowels, getting the cams in is a little tight but easy enough to do.