It is not on the inside it is on the outside of the outer screen. I have tryed the Meguiars with limmited success. Im not sure but could this be reel bad sun fade.
As I look at the unit there are no screws showing on the unit anywere.
Hmm. The 350 must be a friction-fit case, then. Sorry. That's even worse to try and disassemble. You might not be able to swap out screens without serious damage to the housing. Since the fogginess is on the outside, let me ask a couple more questions. I don't want to send you on a wild goose chase, but:
1. Can you scratch the foggy layer at all with your fingernail or thin it out?
2. Does the discoloration feel rough compared to the clear areas?
Based on your answers above I have a couple of ideas that may work:
- If you can scratch the foggy layer off at all or thin it with your fingernail, take a paper towel and soak it in vinegar. Lay the paper towel out on the screen and rub it flat onto the screen so that it is flush against the entire plastic screen. Let it sit for about 10-15 minutes. Remove the paper towel, wipe clean, and repeat if necessary.
- If the surface doesn't scratch but is rough to the touch,
Zymol makes a product called HD Cleanse which is the best fiberglass/paint/plastic restorer I've ever seen. You can find it at some Auto Zone stores and a few other auto parts shops. They just started making a "Screen and Lens Clean" product too but I haven't tried it and it looks like it's pretty much the same thing HD Cleanse. You can try applying it solo and see if it is able to restore the plastic. I've used it on motorcycle helmets and GPS screens with great success in the past. Use it by itself first.
If the above fails, a last resort may be to wet-sand the screen edges using 1500 grit sandpaper, finishing with 2000 grit and buffing to a shine with the HD Cleanse. A friend of mine used it to successfully restore the wind-screens on his 82 Ranger to like-new but it would be a bit trickier on a GPS screen since you can't apply much pressure to buff out the fine scratches that the sandpaper makes. It's a slow process and I'd recommend it only if you really want to spend the time doing it.
Also, I missed your question on reformatting eariler. You can do what's called a "Preset" on the unit which restores everything back to the factory settings but leaves your waypoints intact by doing the following:
"Press the MENU key until the “Preset Sonar and GPS”
label appears. Press the key next to that label. The menu screen
disappears and the LMS-350A returns to the GPS position screen. All
units will be returned to their factory settings."
