860 gt head leak

[wilis]

Hi from Australia,can anybody advise me on leaking head 860 gt,have just reasembled heads after doing valves and have oil bubling out of rear head,has new o rings,while apart i had tubes rechromed would this add to length of tube and stop head from seating fully.thanks GW

[wdietz186]

What comes to mind is possibly one of the dowel pins is cocked or has a burr that is holding the head off or you have a stud pulling out of the case.Did all the nuts torque up evenly? The bevel tube could be hanging up on the orings that seal it,try spinning it and see if it moves up or down[it is hard but it can be done] I use a pair of pliers with soft jaws. It is always the hardest head to get off that messes up isn't it?

[radecal]

G'day GW,
Is the oil coming from the head joint?
If so, good chance you have pinched one of the o-rings. This happens a lot on the rear head if you are not totally careful.
Probably need to lift of the head a little bit to check the o-rings out.
I use a dab of Hylomar to stick the o-rings in place before dropping the head but have still managed to stuff up on occasion.
Hope this helps.
Regards,

[wilis]

thanks for the help,after checking all possible causes ,oil dowels etc for restrictions,i found that on the suface of the head that the cylinder sleave fit up against had a raised section in aluminium on the area that was leaking,not allowing the head to fully seat,hopfully this was problem, will keep you posted on the outcome. can i run 20w50 oil.thanks again

[wilis]

head back on no leaks,the problem was the raised section on the the side of the head that cylinder sleave fits into.GW