Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
These should not leak if the studs are sealed and the O'rings are up graded
The head studs that can leak are the ones that the towers slide over and they have a M6 washer and M6 nut. If the stud thread is not sealed with thread lock, oil can weep down the thread to the spark plug area.
After a complete failure to get any oil pressure in my CB750K1 engine after I rebuilt it, a worried query on here sent me off to Boots to buy a tub of generic Petroleum jelly (it doesn't have to be Vaseline by brand).I took the oil pump apart and packed it with the stuff, then tried again. Instant success! Oil appeared in the oil gallery at last, then in the cambox. I believe some old American V8s use the Vaseline technique as a matter of course to get their oil pumps started. The jelly simply dissolves into the oil, and wont damage or block anything. One wonders if Honda did something similar at the factory, I recall reading that they came primed with some sort of fishy oil that had to be replaced before use, the ex Honda workshop guys on here may be able to confirm that.There was also a very sad thread on here from a member who put all his effort and money into a rebuild, then started his CB750 up without checking for oil pressure. the result was a beautiful rebuilt bike with a freshly ruined motor. As I remember it he was too disheartened to pull the engine to do it all again, and sold the bike 'as is' for someone else to fix.
Yes packing the pump with Vaseline is standard practice when building Rover V8 engines so the pump can prime itself Sent from my iPhone using Tapatalk