A couple of months ago , someone posted that the inside dometic tempature rose a few degrees just before the frig kicked in for cooling. I think this is the added heat from the burner on high. Because of this ,I suggest a aluminum flashing material between the cooling fins and the rear of the dometic. Like a heat shield on a muffler.Just a small break in air space is all that is needed(thats all your gonna get).

Also a sheet of fiberglass insulation on top of the frig.

Sounds like removel and a regooping of the aluminum evaperator may help you. It just wiggles off. Be careful of the thermistat probe that is behind the plate.

Radio shack has a thermal heat sink compound in a tube that will work(1 tube).When the plate is reattached, be careful that the plate is not pressed on directly over the left end of the balck pipe. This end cap is of a larger diameter than the rest to the pipe, and it will cause the plate to not seat properly.However, this end (where ice is made) is also the coldest part of the black pipe. Place the plate as close to the end cap as possiable.About 1/4 inch away from the end.Capture as much"cold' as possiable.

The heat inside the frig is conducted into the aluminum fins and back to the black pipe. The actual place where the metal to metal contact of the balck pipe and aluminum plate is made , is about 1/2 inch wide, and 9 inches long.It is the aluminum extrusion flang. 90 percent of the heat removed from the inside of the frig , goes through this small area.The remaining heat is conducted through any extra surface area on the black pipe that is not covered by the plate flang.This is why proper contact of the two pieces is critical.The origional green mastic can dry and crack. Any air gaps that result, reduce this contact area.Air gaps,no mater how small,result in air to metal heat transfer.It is 1/25 as efficent as metal to metal or water to metal, heat transfer.When your talking about 4.5 sq.inches of surface area, any bubbles are too many bubbles.

Look at the automatic transmission cooler in the radiator of an american car .It is puney. This is because of the efficent heat transfer of water to metal,and fluid to fluid. The radiater that this cooler is mounted in uses air to metal, and needs to be as large as it is. Another water to metal device is the oil cooler on the vanagon diesel or 2.1. Dont underestimate it.

The contact area of the two components , in the frig, may(dont know for sure) actually be increased by adding a fillet of a thermal compound of some kind on each side of the 1/2 inch area.Perhaps a heat sink mastic of some kind. I wasnt successful in finding a good material last winter.What I tried, drooped and smeared. Perhaps a layer of some material can be added on the bottom edge,with the frig installed by using your finger to apply it.

Also, the door sealing needs to be checked ,some way.

When you burp it, tap the pipes with a rubber hammer every few hours or so.

Type in "manometer" in yahoo, and find instructions for making and using a manometer($2). Check our regulater pressure.

The brass orifice will almost oxidise closed in 25 years.Rubbing alcohol will not not not remove this oxidation, and you are wasitng your time with it. I borrowed a tiny bit of battery acid and diluted it 4 to one. I attached a rubber hose to the orifice and let it drip through. With the manometer, I compared it with a new brass orifice. It matched in the ammount of time it took a collum of water to rise 11 inches.Previously, with a alcohol bath, I got no change.The collum of water took much longer to rise to 11 inches.Now,you can rinse it in alcohol when the acid has done its thing. A ruby orifice in late vanagons is different, and may not clog as easily. Rubbing alcohol mahy help it. Ruby orifice,$80.

Dont toss your dometic or trash it verbally till you do these maintianance proceedures.Toss it my way if you need to vent. It will work better. It is rare that a ammonia circut actually gets clogged. Many blame the bad dometic preformance on this.