How do I open it to clean up - Jack Lalanne Power Juicer (Stainless Steel)

This depends on the juicer you have.

Search for the directions booklet online of the model number and type of juicer you have.

There is one model that requires a key to open. See this video at 1:25 in. Jay Kordich Power Grind Pro Juicer Review Part 3 Cleaning the Juicer
If you have the model not made with the key, you hold down the silver button on the side (NOT the power button lol) while pushing down with your hands flat on top of the orange rim part and turning it to the left. You'll feel it start to unlock and unscrew.
Voila :)

Assuming you are dropping down the metal arm, removing the plunger and the rear pulp collector: everything unscrews from there. Hope you did this immediately following the juicing as it gets sticky and can be hard to open if you waited until it dried. When you get to the screen, it opens with a red tool they provide to unscrew it. Hope this helps.

open the blade? you mean get it out for cleaning? just pop it out by putting a knife or back of a spoon under it and gently pry it up in a few places. works like a charm, been doing it for 5 yrs

I did some research here on Fixya and this is what another expert had to say.........pull the metal bar forward and down to open up into the blade compartment. your juicer should have come with a handle type key wrench thing that you stick on top of the blades into holes to unscrew blade holder, while unscrewing that hold the blade still.
Hope this helps you......best wishes.

http://www.powerjuicer.com/customer-manuals.html

This is the site to download Jack Lalanne's Power Juicer Manuals of all models which include troubleshooting guide, user instructions, cleaning and opening machine.

Hi there: have the same problem, go to www.powerjuicer.com/pdf/classic.pdf.
you will need the crescent tool which I do not have as yet but two screwdrivers work, be careful.

There should be a lug nut in the center that loosens so you can take the blade, basket & outer basket out to clean.

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