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I  am restoring this for a friend.  Serial number 2G-85071.  It has a Tecumseh model 2914 A compressor.  The number P91L is on the tag and P91 is on the compressor itself.  I have disassembled and reassembled the unit.  Prior to me working on it, the owner said it was cooling great (despite the dirty condenser and everything else.)  I know nothing about refrigeration, however I thought I would try my hand at it.  So far no luck.  I bough a used Yellow Jacket two stage vacuum pump, changed the oil and did the best I knew how, to pull a vacuum.  Since I have read several postings concerning the 55, I don't feel real good about what I did.  I JB  welded the evaporator coils to the box, then taped them with refrigeration tape.  I really don't think I have a vacuum leak.  I charged the unit with R12.  When I plug it in, you can track the cooling from the front to the back and watch the temperature drop to about the mid 40's then it quits cooling altogether.  I have one can of R12 left, however, I do not want to keep making the same mistake over and over.  If anyone has any suggestions as to how to approach my problem, I would forever be in your debt. THANKS,  SANDBLASTER.

           Sounds like a restriction in the lines. Did you install a new dryer in the system? The original one was pretty small.

No sir, I did not.  Did not even think about it.  It would have been above my pay grade anyway.  The compressor comes on as does the condenser fan.  If I have my lines right, the high side line going to the top of the condenser coil is warm and the low side is cool.  There is frost of the low side line as the cooling coils progress from the front to the back you can feel the tub sides getting very cold. Then in about 15 minutes, it stops cooling.  The compressor and fan continue to run, however the compressor starts to get pretty hot.  To replace the dryer, I would have to take it apart again, right?

          Yes, the line that comes out of the condenser has a mini drier that's getting plugged up.  Cut there and install your new one.
 Do you have any way to recover your freon? 

Yes you will have to take it apart to install the dryer. It sounds like you have ice forming in the capillary tube due to the system not being free of all moisture. Installing a drier and pulling a vacuum to 500 microns or (pull a vacuum for a couple hours) to ensure all moisture is removed from the system. I use a Sporlan CO-32_FM drier with a 3/8 female to 1/4 male adapter for the inlet and a 1/4 female to 3/8 male adapter for the outlet. It keeps installation simple and requires no brazing. Hope this helps.

Or it goes pfffffft.  :Oo:   Welcome to the site... So, you MUST change the filter dryer out whenever you have exposed the original system to atmosphere , especially when you have since you had it apart sitting around disassembled, waiting while you worked on the rest of the machine.

Just curious...You said you changed the oil, what oil came out & what type of oil went back in? Reason being is synthetic refer' oils just LUV to absorb water vapor from the atmosphere (they are very hygroscopic), and it will cause Icing in the capillary line as you have found out.


New Filter dryer.

Deep vacuum.

Check for leaks, (if you don't have regulated dry nitrogen, then use a light charge of cheaper R134a & bubble check [I assume you don't have a sniffer]) Deep vacuum again, recharge system with your R12...good luck & don't volunteer for the bomb squad... ( they're all Blue wires sir! :tounge:  )

Thanks for the information about the dryer.  I found one on e-bay.   If I understand you right, the dryer with adapters, actually fits between the tube coming out of the condenser and the liquid line going to the evaporator.. Johnny G.  I bought  the compressor oil from NAPA.  It said it was wax-free mineral oil for use in are-12 automotive systems.  Let me know if it is the wrong type and what kind I should get. 
Thanks for everyone's patients.

MO (mineral Oil ) is correct.

I have successfully installed the dryer, vacuumed the system and recharged it.  The box is keeping a constant 32 degrees, however it is icing around the top of the box on the inside front and back. As part of the restoration, I put new rubber and a new stainless steel top.  The top is not making a good seal.  Would this cause excessive icing ?, or could it be over charged?  This forum and it's members have made it possible for me to be able to finish an otherwise very frustrating project and I thank you.

It's suppose to .

Yep - mine does the same, especially in the summertime. 

The saga continues.  can I get someone to explain to me how to tweak the cut off point of a thermostat.  I bought a replacement thermostat from fun-tronics for my Ideal 55 and it has two small screw holes on it.  The one on the left says cut out, an arrow with the word cold pointing to the second screw that says cut in. I have placed the sensor end inside the end door, against the wall and even with the temp at below freezing, I the compressor will not cut off.  I places an inline light to indicate when power is going to the compressor and it will not go out.  I had stated in an earlier post that the box was keeping a constant 32 degrees.  That was a little premature.

Cut-out = it turns off when the temperature falls to the low setpoint.

Cut-in = It turns on when the temperature rises to the high setpoint.

How long are you letting it run ? I just put one on my deck and its 100 degrees out and it took a out 4/5 hours to cool down to 40 degrees . It now is running perfectly cutting in an out on the hottest setting (1) about every hour .
These machines will piss you off . Just let it run for a day and see where it's at .
I ran the sensing prob to the first screw on the divider tray and mounted it between the liner and tray .