Bissell Lift-Off Deep Cleaner - Tank yellowing

[niclonnic]

I've owned this deep cleaner for over 5 years, and have just discovered this issue today.

Today I went to clean up some cat vomit stains using this machine in portable mode, and I found something peculiar. When I removed the clean water tank to fill it up, I noticed that it was starting to turn yellow around the back and sides!

Now, I clean this machine thoroughly after each use and let everything air dry before storage. I have no idea how this happened.

Is this a normal occurrence with Bissell machines, or just wet vacuums in general?

I am uploading a couple pics below, taken with my phone, an iPhone 6s Plus. The yellowing doesn't really show up with its camera, but it's a lot more pronounced in person.

 

[carolinaguy1996]

Reminds me of some retro game systems with crap plastic.

 

[niclonnic]

OK...

What do retro game systems have to do with this? I'm talking about a carpet cleaning machine here.

 

[carolinaguy1996]

Calm your jets down...

I was making a comparison.

 

[hvrvaclvr]

Must be common with wet vacuums, my Floormate's clean water tank has yellowed. and all of my rug scrubbers (portable and uprights) have done this too.

 

[tseg]

I wonder if it is like the oxidation that occurs to acrylic car headlights over time turning them yellow and cloudy? Maybe the various compounds to 'refresh' those headlights would work here?

 

[carolinaguy1996]

You can de-yellow it, I'm sure.

 

[niclonnic]

Huh...

This yellowing issue hasn't happened to the other wet vacuums we've owned. This Bissell is the first to do it.

I wonder how it's possible to de-yellow the tank on my Bissell?