Howdy gentlemen,

I searched the forum and didn't see this issue. It's a no-brainer for a pro.

I have an old Whirlpool dishwasher (1991? 1996?? - serial number ends in 19916) that works like a champ despite being fed a steady diet of very hard well water.

The rubber diaphram ("nozzle cap" ??) on the lower spray arm has taken a beating from the hard water and I'd like to replace it.

Does it require a special tool or just a strong wrist? My well water tends to act like cement, so is there a danger that too much elbow grease will break something?

Thanks!!!!!!

Thanks for your response Gene.

A couple of followup questions:

1. the parts diagram shows a washer/bearing between the lower spray arm and nozzle cap (see attached image). Should I replace that too?

2. I use undiluted white vinegar around my house to remove hard water deposits (diluted vinegar is worthless). However, plumbers have warned me not to use it in places like the dishwasher or toilet tank because it will eat away rubber washers and seals. (And it will - I've seen it happen on my faucets!) Are you saying it's safe to use in my dishwasher tub?

Thanks!

You can also use Dishwasher Magic. It works well, but more expensive than vinegar.