Kioti NX AC Compressor replacement - Is there oil in the new compressor? - Also - Clean your evaporator!

[Overtaxed]

Well, not too thrilled I have to do this, but I'm about done replacing the compressor in my NX. I can't really blame Kioti, I lost compression and think I got dirt in the system. For those with an NX, look up, above the fuel tank and make sure your lines are well secured! Mine fell onto the tank and then, many hours later, finally gave way after the friction wore a hole in the elbow. Simple problem, expensive fix. Good news is that changing the compressor and condenser is pretty easy, just need a few extensions and elbow fittings on a ratchet. The manual says you have to remove the DPF, you don't as long as you have enough flex in your wrench setup to get around it.

Because I need to clean out the lines, I had to open the roof to get at the expansion valve. While I was up there, I decided to open up and look at the evaporator. OMG. What a mess, while I think the cause of this was what I described above, the evaporator was so dirty I cannot believe it worked at all. Although it's not mentioned anywhere in the manual, this should certainly be a job that's on the list to look at occasionally. It's also kind of a tough job, you have to pull off the roof, then, rather than take everything apart, I pulled the fans off to come at it from the back. I have the stuff to clean coils/evaporators, so I just sprayed in it and then gently sprayed water in to clean everything up. This is where your drains are, so all the sludge made its way to the floor. But man, did it need it, what a mess up there.

Finally, I chatted with my dealer this AM and we're not sure if there is oil in the new compressor. Typically there is, but, I'd like to double check before I flush everything and pull a vacuum. Last thing I want is to do this job again! Anyone know if Kioti ships their compressor pre-filled with oil?

 

[Overtaxed]

Well, I THINK I have my answer. I called Kioti, they didn't know, but said they'd research it. They did and called my dealer. The dealer called me and net/net, sounds like it has the "right" amount of oil in it already, shouldn't be adding any.

Not exactly confidence inspiring though. AC systems have pretty specific requirements for oil, they are supposed to have 8oz, or 10oz, not "some", or "about a 1/2 a cup". A lot of auto AC compressors tell you, right on the label, how much oil they put in. Then you can look at the manual, figure out what else you're replacing (dryer/evap/hoses/etc) and determine how much more you may need to add. The answer I really wanted was "We put 8oz in before we shipped it" because then I could figure out how much oil I may need to add for the other components I changed.

 

[Overtaxed]

Updating this for anyone else in the situation, the initial answer was wrong. The compressor does not have the full load of oil in it. It has "some" for shipping from the factory. Not a definitive amount. Kioti recommended 4oz of oil added which.. Well, doesn't make any sense. The total system capacity on my tractor, per the service manual, is 100G. 4OZ is more than that; and I didn't replace the entire system (there some oil in each component of the system, the lines, the evap/condenser, etc). So adding more than the full system load when you're only replacing the compressor is... Well, it's wrong, or the manual is wrong. And there is "some" oil in the compressor from the factory, making a 4OZ load even more suspect.

Pretty annoying. AC systems really want to have the "right" amount of oil. 1oz in either direction, while not the end of the world, is still 25%+ under or over charged. So to do this right, you really need to know exactly how much oil they put into the compressor in the factory, "some" isn't super helpful.

Anyway, I added 2oz of oil to the system today. I figure that's about as close as I can get, I know the compressor had some oil in it, and I didn't flush the evaporator, so I know there was some there too. Should be pretty close to the ~3.75oz that the system requires. Everything is running well, but it really bugs me that I don't have the exact correct amount of oil in there. These systems can be sensitive, you don't need it within a gram, but it would be nice to be within an oz. And, worst of all, if you're off, you won't know it until the compressor gives out (again), there's typically no warning signs when you mischarge with oil.

I'm probably overthinking it, but my family has a long history of working in industrial refrigeration, when something needs 10.35lbs of Freon, you don't put in 10 or 10.5 lbs, you put in 10.35. Systems last longer, work better and more efficiently when they are correctly charged.

 

[Threepoint]

Overtaxed, thanks for your write-up on this.

I'll be checking my compressor lines on my 8 y/o NX tomorrow. Just in case.

 

[MinnesotaEric]

Look on eBay. I just saw a new Kioti compressor for $239. New Genuine OEM A/C Compressor for Kubota / Landini / Kioti / Massey Ferguson RQ | eBay

 

[AdamB]

Overtaxed,

Where did you find the refrigerant type and capacity? I have to replace my doowan dv9 a/c compressor and the only thing I see is it takes PAG205A oil. No refrigerant type or capacity.