Where can I find a user manual for a kenmore dishwasher model number 665.1687581

I googled your model number and it appears that your request is not unique. A lot of people are looking for that manual. ManageMyHome (Managemyhome.com) is the usual place to look for Kenmore manuals. They also didn't list your model number. However, I googled "Kenmore Dishwasher 6651687" and they show three entries.

Manage My Home - Managemyhome.com

See if one of these isn't your dishwasher -- or at least very close to it.

The other possibility is to look on Sears PartsDirect:

They do show an entry for that model, but they don't show an owner's manual. You might call Sears Parts Direct and ask them (click on "Contact Us").

KENMORE | Model #6651687581 | DISHWASHER | SearsPartsDirect.com

My kenmore ultra wash dishwasher just broke too, I was able to find a REPAIR manual on Ebay for 5 bucks for a pdf file instant download.

His site is: eBay Seller: yuliyag: Computers Networking, Home Garden items on eBay.com

Note: Lots of Kenmore stuff is a Whirpool inside.