dk55 ac questions

   / dk55 ac questions #21  
I have done some work on the DK55 air conditioning in the past and I can offer you a little help. Had a 55 freezing up a few years ago and had gone through all the cleaning processes in the cab with same results. There were no air bubbles in the receiver dryer sight glass, so I discharged the system. I removed the receiver dryer and found rusty contamination inside of the connecting lines. It life span had been used up, so I replaced it. Upon talking to a factory rep., he advised to replace the expansion valve also because the contamination could of partial plugged it. I added a few oz. of lube oil to the compressor, evact the system and charged with the proper amount of freon. The customer said the air was running alot colder, then when he had purchased the tractor from me new. Hope this helps, trac
 
   / dk55 ac questions
  • Thread Starter
#22  
Ok so ive switched relays around and found no change, in that both relays still function. so ill try the uncharge and recharge system next and ill look into those parts "Trac" is talkiing about this sight windo is on top of the dryer right so that is were the bubbles will appear? any way the tractor is 7 years old and might not have an electrical problem just old freeon that needs changed.
is the expansion valve located after the dryer in this picture part number 2
 
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   / dk55 ac questions #24  
The expansion valve is normally between the dryer and the evaporator. That should be #2-valve B. I'm not sure what #1-valve A is. Perhaps TRAC can shed some light on what both valves are. Replace the receiver/drier if you are going to open the system. The old freon should be recaptured into a recycling machine and the prescribed amount installed. You will also need to add refrigerant oil specific to your system. Each componet holds a certain amount of oil that needs to be replenished and the manufacturer will usually list the amount in the service manual. It is important to evacuate the system before recharging to remove any moisture. I would expect to see some bubbles in the sight glass, even on a fully charge system. If you do not see any bubbles it may be overcharged and cooling will be diminished.
 
   / dk55 ac questions
  • Thread Starter
#25  
i wont try this job myself. i dont have the tools or the experiance to do it but ill have the new parts ready for who ever i hire to do it.
 
   / dk55 ac questions #26  
Looks like the switch wires are NOT connected to the switch screwed into canister with the rusted threads in one of your pictures. If that item is your receiver/dryer I would replace it. One of the other pics shows the amount of compressor oil necessary to be added on a recharge, and the type of oil to use. You need to have all the new parts ready for use before opening the system lines to reduce excess moisture from entering into the lines. Once opened after draining out the old freon for recycling the new parts can be installed. Find out if you should be using pipe dope or teflon tape on the threaded items like expansion valve and receiver dryer- a competent ac/tech will know what is being used these days.
Once a vacuum is drawn and it holds for the required time to verify no leaks in the system then it is time to add freon and oil to the system.
Then you can check temperature at your cab vents with a thermometer, and flow of freon at the evaporator/canister sight glass. Note max temp and ambient temp for future reference so you will know when the system is not producing.
One other thing you may be experiencing is a bad compressor clutch if the relays and switches are all working correctly. I'd call Paige tractor and have them determine which parts you need for your system instead of guessing which parts to buy- that could be costly if you get incorrect non-returnable ones.
 
   / dk55 ac questions #27  
Find out if you should be using pipe dope or teflon tape on the threaded items like expansion valve and receiver dryer- a competent ac/tech will know what is being used these days.

Thread sealant is not necessary. Lines and fittings use o-rings and should be replaced.
 
   / dk55 ac questions
  • Thread Starter
#28  
sic10844, thats why i made pictures i would have never noticed that sticker telling what type and how much oil to use thanks for pointing that out. I disconected the wire on the dryer to take the picture.
 
   / dk55 ac questions #29  
sic10844, thats why i made pictures i would have never noticed that sticker telling what type and how much oil to use thanks for pointing that out. I disconected the wire on the dryer to take the picture.

You're welcome!:D
 
   / dk55 ac questions #30  
On this type of system of a tractor, the manufacture is more concerned about high pressure. The switch on the dryer is set to shut off the compressor at a certain pressure well below blowing out the sight glass . I have seen this happen so, never bypass this switch. Pressures can run 100psi + outside ambient temps. It's best to hire an expert to do this work so, it is done correctly. As previously stated, you will need a receiver dryer, orings. I like to use 134A with the dye in it on older tractors, so leaks can be spotted in the future.
 

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