CRT Coolant: Who would've thunk of that?

We bought our rear projection TV (RPTV) several years ago, and since we moved (temporarily) to Denver, each time I went home I noticed that this TV is getting dimmer, redder, and the pictures looked terrible. The videos are really hazy, cloudy, and bright objects have this halo effect. See the pictures below. I got these pictures from the internet and cropped it, but mine looked just like it.


The last time I was home (early October), I took the back of the RPTV apart thinking that maybe the lens on each of the CRT guns (red, green and blue) are dusty after all these years. Sure enough, when I got to the lenses, they are covered with a fine layer of dust. I cleaned that up, and put everything back together. The TV picture looked much better than before, but it was nowhere near what it looked like when it was newer. Look at the pictures below after someone else did his coolant work. I hope to be able to do this too soon.


A few days ago, I decided to google "cloudy picture in rear projection TV". The result surprised me. I was thinking that maybe my cathode ray tubes (CRTs) may need to be replaced. But as it turned out this is a typical symptoms of CRT coolant getting contaminated, and the coolant developed growth that looked like algae. Who would have thought that a rear projection TV have coolants, and this coolant turned opaque because of some unknown growth?

Evidently, on this vintage of RPTV with CRT-based lamps, as opposed to liquid crystal display (LCD) projection TV, there are liquid coolants (ethylene glycol) in each of the CRT color guns that resides between the CRT face and the lens. This coolant protects the CRT from overheating and burning the phosphor coating. Ethylene glycol is the same basic liquid used in your car's radiator to cool the engine. For RPTV, the coolant is the clear variety. Someone explained that the coolant, in the presence of heat and contact with the metals that contained the liquid started to develop algae like substance, and thus changed the liquid from clear to opaque. Another interesting fact is that in almost all cases, the blue CRT coolant is the worse followed by the green CRT. The red, according to these folks, almost always is least affected. Thus the prevalent reddish color. So, after reading these articles and checking procedures on how to do it, I decided that I am going to try to correct this problem. I found an electronic supplier that charged about 9-10 dollars a a bottle plus about $9 in shipping. Then I found on eBay a seller that will sell me 3 bottles for $25, with free shipping. It is now being shipped directly to Rockwall, and I hope to be able to work on it during the Thanksgiving break. I will try to remember to take a picture of before and after.