Thread: NS Oscar I - Can’t turn the steam knob

Sounds like the valve has stuck (maybe caused by formation of a vacuum). Try opening the valve before turning the machine on when you get home, and leave it that way while the machine warms up.

Originally Posted by Barry O'Speedwagon

Sounds like the valve has stuck (maybe caused by formation of a vacuum). Try opening the valve before turning the machine on when you get home, and leave it that way while the machine warms up.

Awesome thanks Barry. I’ll keep you updated on whether or not I can turn the knob when I get home. If the knob still won’t move when I try, what’s my best move? Open her up and undo the steam valve or something?

So update: steam knob is still completely stuck. I will take the top off and have a look at what’s going on with that valve.

Originally Posted by ultralightmeme

So update: steam knob is still completely stuck. I will take the top off and have a look at what’s going on with that valve.

Are you able to take the knob itself off on this machine? I'm guessing not.

Originally Posted by Barry O'Speedwagon

Are you able to take the knob itself off on this machine? I'm guessing not.

Does taking the knob off normally require a pair of pliers? Because my hands can’t get the knob off

Originally Posted by ultralightmeme

Does taking the knob off normally require a pair of pliers? Because my hands can’t get the knob off

I don't know how it works on an Oscar. Better off waiting til someone more familiar with this specific machine chimes in.

Can you confirm that the knob won't turn in either direction?

Just found this, doesn't tell you much other than others must have experienced similar and the solution may be a new valve.


"My steam knob has always been hard to turn, gets very tight and sometimes gets stuck on or off. Now, it just turns freely, does not tighten or stop and does not control the steam wand, so I can not froth milk or set the steam wand to leak when warming my machine up. Is this simply a matter of ordering a new knob and replacing the plastic part, or is it more complex? Is this a common problem for the Oscar? Thanks!

Posted by Anonymous on Dec 21, 2012
1 Answer
You need to replace the steam valve"

Why not give Jetblack espresso a call, they carry the Oscar, and may be able to help

• (Call us on (02) 9452 6470 (Sydney Store) or 1300 747 873)

Elektros show the part (I think) and it seems the knob pulls straight off. It may be grub screw retained on the side, or a screw in the middle.
Screenshot_20190430-180922.jpg

Pulls straight off.. surely?
Screenshot_20190430-181626.jpg

So eventually after pulling everything apart including my hair, I got frustrated, used my wrench on the knob to breaking point and just forced it, and damn it, it actually worked. Unfortunately I have huge marks dug right into the knob now. I still have no idea how it got jammed so hard.

Time to look into a lever mod for this thing...

Originally Posted by Jackster

Pulls straight off.. surely?
Screenshot_20190430-181626.jpg

I’ll try yank it off and let you know if that’s the case haha

So new seals, seats, spindles and knobs are available...