Oil leaking from cylinder head chrome nut!

How about a dab of sealant?
Steve

Now why didn't I think of that !!!
Great idea, thanks. I've got some RTV gasket so I'll try that.

can't see anything about copper washers in my manual ( but then again, it's a Haynes !!)

Haynes manuals are great - If you 'd bothered to read the fucker the leaking stud fix procedure is also detaled in the Haynes 750/4 manual too:

Page 80 / 43 /1 'refitting cylinder head' (also interestng info on 83 model oilway and head gasket redesign)

Page 48 '/ 19 / 1 'Examinaton and rennovation crankcases and fitting.

Hey, calm down.
You must have a different Haynes manual than me as there's NOTHING about copper washers for the head anywhere.
My haynes manual is for 76_78 models & here's page 36 with the parts for the head.
Have a nice day now.
By the way , I ordered some copper washers yesterday and today they arrived.

You must have a different Haynes manual than me as there's NOTHING about copper washers for the head anywhere.

That's because I don't think there are any. As I tried to point out earlier, the 650 mill oil circuit is quite different form the 900 series most of the guys here are more familiar with. The studs are dry not wet.

Usual oil leakage on these is the oil passage o rings either side of the block. Kawasaki later revised the part number of the oil jets and the head gasket.


I don't see the point in slating Hayne's manuals particularly if you don't apparently have the FSM and updates to make a valid comparison to. Have a nice day.

As Tyrell mentioned, the 650 oils the head via dedicated passages with calibrated, removable restrictor orifices, as shown in the oil flow diagram part #7. That is also how it is done on the 550's. That is different from the large-block motors. They use roller bearing cranks and don't need high pressure at the crank, so they don't need restrictors for feeding the head.
Open it in a new tab to blow it up.
www.dansmc.com/kaw_kz650_oilflow.JPG

It still seems strange to have pressurized oil coming up the stud passage.
Maybe the leakage from the stud nut indicates a broken seal at the head or base, and oil is just routing into the stud passage?
Is it possible the crankcase vent has been blocked off?
I can't see the photo in the first post so I can't see the leak, but is there any chance oil is leaking from elsewhere and pooling at the stud nut?

Z1enterprises do sell orings for 650 studs, but they say it's for the two inner, rear studs.
www.z1enterprises.com/catalog/product/vi...nder-stud-kz650-750/

Here's my missing photo of where my oil is coming from.

Buxvan image:

I'd like to see a front and back view of that area of the head. Your manual should have a flow chart.
Steve

Here's a video of my cylinder head.
Thanks for your replies. ( I fitted copper washers but still leaking from the stupid nut area !!)
You were right, I'm wrong !
Still not a fan of Haynes manuals though.
Will buy a kwaka one when I can find one.
Can't get my video to load so hopefully a few photos.
Also I have noticed what looks like an epoxy resin or something on the fins underneath the nut. Now I'm starting to get worried !

Because that nut was not meant to seal against oil pressure, they may not have machined a "sealable" finish into the part of the head that the nut presses against. Because of that. the copper washer may not be sealing. But even if the copper washer sealed it, there would still be a broken seal somewhere else causing the oil to come up in the first place. This means if the copper washer seals it, the oil is probably going to leak out somewhere else.

The important thing is to be 100% certain that the oil is actually coming from the stud bore. This means ruling out the possibility of it leaking from the valve cover and running down that casting line to the nut boss. Or coming up through a tiny crack somewhere else.

I would probably get a can of engine degreaser and wash the area till it spotless and bone dry. Then let it idle until the first hint of oil showed up and sprinkle some fine graphite dust (pencil lead) or something on it to see where it sticks. I'm always suspicious of the cam end plugs and valve cover gaskets. Even with the best of photos, it's almost impossible to see tiny oil leaks where oil might be traveling from another area. It would be much easier if the oil had some fluorescent die in it or something.

After i take a closer look on the oil flow chart, i am with loudhvx, there must be a little crack in the head casting