We suddenly have a yellow green tint on our Sony SXRD widescreen projection television. We were unable to change the hue when adjusting the controls. Is the monitor going bad and if so is that a major expense where it is cheaper to buy a new tv?

Sorry to hear this, but your optical block has failed. Sony replaced a ton of these under warranty and then extended the warranty on these SXRD sets so they could replace many more. They even replaced the sets with LCD sets after a class action law suite. This was a "black eye" for Sony TVs and they stopped making the SXRD sets. Your set is vintage 2006 and there is no longer a warranty. You could replace the optical block with a rebuilt one, but the cost would be about the same as getting a new 60" LCD. I would suggest you do the latter.

I have a older 2006 SXRD rear projection TV. I had the same problem after the TV warmed up this yellow tint started in the corner and crawled its way down the TV. It turned out that Sony had a recall on the optic block of the TV. If you replaced the Lamp and adjusted the color this kinda sounds like the same problem. Here is a link explaining it. In this article it shows up as a green haze and blob, but in my TV it manifested as a yellow tint.
http://www.avsforum.com/avs-vb/showthread.php?t=1086180

You have a light engine problem and you may be able to get sony to fix it for free. Go here and read throughly.
http://sites.google.com/site/sonylcdrptvproblems/

Hi,yes if you get a blue hue is has to do with the optical block .You can find it here : http://www.discount-merchant.com/SONY-1-867-732-14-Light-Engine-w-Color-Wheel-p/1158118.htm?Click=48173 maybe youcan find instructions on ebay.

Called them today and they set up appt for installation of the required part. They admitted a "known problem" and were straight forward about offering to take care of the problem, No fight necessary. Have the model and serial number ready off the back of the set.Call them ASAP

bad light engine call sony and see if your tv is one on the extended warranty list.

This may be due to Optical block. Click the link below to review Certain 2006 Model Year SXRD Television Extended Warranty Information - Optical Block

http://esupport.sony.com/US/perl/news-item.pl?news_id=277&mdl=KDS50A2000

Since you have eliminated the bulb, you must now carefully and meticulously clean the optics and lenses in front of the bulb.

http://www.breakitdownblog.com/class-action-lawsuit-against-sony-for-green-haze-or-green-blob-sxrd-problem/

Component Video Jack was loose.