Air Conditioner Bolt Loose?

[Condoluminum]

On most recent short trip, I noticed front corner of A/C Plastic Diffuser no longer flush with roof, and dropped down almost 1/4".. It was possible to lift it up and there was a lot of play in the front and left side..

After removing the plastic panel, I looked inside and saw the bolt head and washer down about an inch and apparently in the act of falling apart.. (See photo below..) Unit is a Coleman Delta TX on an '88 Excella.. I had a shop remove upper unit and replace gasket two years ago.. Do I have reason to go back and complain to shop, need to find another one or is there an easy way to remove upper cover and replace nut with good locknut? The bolt head is hard to reach between sheet metal of base of unit, and adjacent to heating wires for warm air...

Suggestions or photos showing how to attack problem appreciated...

[Melody Ranch]

I do not think there is a nut at the top of the installation. It should be a nut plate type fastener....your bold goes in from the bottom....and is definitely loose . Tighten it up yourself to prevent leaks and secure it.

[Condoluminum]

Just a quick update and THANKS to Melody Ranch above... The Nut Plate concept is accurate, and with a few more sheet metal screws removed, I was able to get at it with a 9/16ths socket and tighten it back up again.. In the process, discovered that rear one loose by 6 or 8 turns, and front left also not really snug either... Hopefully saved both a future water leak (we can't tell for sure in this part of California until October...) and also a certain hassle trip to a repair shop... I wondered why no lock washers, and will see if they loosen again and perhaps add them if unit comes loose again... Tightening against foam "gasket" I don't believe bolts should be really super tight (high torque..) since odds of compressing/deforming gasket increase.. We'll see...

Thank goodness for this Forum!!

[Wazbro]

If they come lose again try putting some locktite on them (the kind that can be removed).