Quoted:
CM, I wish I could buy you a six pac of beer and 500 rounds of SA surplus so you could show me how to change the cooling liquid on my Magnavox, fix the one convergence adjuster that is stuck and how to clean the dust off of the back of the electrical stuff in the back without getting zapped.
I did manage to clean the lenses and the mirror and I sealed up the interior with flat black duct tape.
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Maggotboxes are pretty easy to change the coolant on.
Just remember to ground the anode lead to the chassis, using a LONG screwdriver, after unplugging the unit and before trying to disconnect the anode cap!
If you understood that, you're going to make it through the fluid change just fine.
First, unplug the unit. Then, take the lower back panel off. You will then be able to look and determine if the upper back panel (the big one) needs to come off, as well.
Heck with it. Take it off anyway because the rear mirror probably needs a good cleaning in any event. That'll help the picture quality out noticeably.
The tube and projection lens assemblies are secured to the chassis with four bolts. Note carefully the orientation of the tube, the mount, and the lenses. Mark them or take pictures if needed, because you can reassemble the unit incorrectly and then nothing will work right. The cables won't reach the connectors and the expansion chamber will be on the wrong side.
Remove the anode lead from the HV splitter block by twisting the cap and pulling the lead out. (On most maggotboxes, that's all there is to it. If it doesn't come out easily, DON'T pull harder!) Keep your distance from the open end of the anode lead because it's in need of discharging. Discharge it only to the metal chassis frame, with a long screwdriver shaft. Screwdriver to frame FIRST, end of lead to screwdriver shaft SECOND. Discharge it several times over the next minute to be sure it's dead.
Disconnect all the cables and the ground straps.
Carefully pull the CRT/lens assembly out of the projector, being extremely cautious so as not to knock the connector end of the tube on anything. If you break that glass, you're hosed. New tube time. Money.
You now have the tube assembly out of the projector.
Got a plastic drain pan handy? You'll need it.
Unscrew the white plastic reservoir and drain the tube assembly into the pan.
Remove the four bolts that hold the lens assembly to the frame that the CRT is mounted in. The lens can now be separated from the CRT, and here comes some more fluid dripping out.
Using WINDEX and not some other brand of glass cleaner, (because you need ammonia and some other brands don't have ammonia in them), thoroughly douse and wash out all the lens surfaces and the interior of the coolant cell.
Be very thorough and let it dry totally before attempting reassembly. Even go so far as to rinse out the white plastic reservoir.
The gasket MAY be reusable, but it's better by far to buy new gaskets from your Magnavox service center. And if you're dealing with those idiots, get some of THEIR coolant fluid while you're at it, too.
The job really isn't all that tough. It's an evening's work to do two tubes if you take your time and haven't done it before.
Stay cautious. Don't bugger the neck of the tube!
CJ
Assembly is the reverse procedure.