air conditioner parts

Im working on a 5740c Montana tractor and need a little help. The ac condenser has a hole in it and I need to locate a new one. Does anyone know of a company to buy these aftermarket so I don't have to go to the dealer. The only name I can find on the system is Korea climate control and that is on the compressor. Also what will cause the high side to go so high it will blow the condenser. Possibly the expansion valve? The unit has a site glass and about the time it cleared up the condenser blew. The unit was starting to only slightly cool

Just had a neighbor trade one off because he had no air and has been waiting on the part you are needing since March. He had about the same thing you had happen. Carried it to a shade tree mechanic and they shot some Freon in it. Blew it up and could never get the parts. He took a beating on it but got rid of it.

Chances are the system was overcharged. I'm guessing this was originally R12, converted to 134.

Trying to charge 134 with a sight glass will overcharge it. You have to charge with gauges and charts.

Also lack of air flow through the condenser will cause high pressure, as will kinked or restricted lines. While it's open, remove the expansion valve/orifice, replace if in doubt, replace the filter dryer, flush the system with aerosol flush, check for blockage.

As for finding a replacement condenser, try some vintage automotive ac suppliers. They can work from measurements and fitting size. Probably be much cheaper than the dealer.

No the unit has not been converted and no the unit was not overcharged.

Your finding out two things:

1) Charging a AC system without weighting the Freon can easily result in it getting the system over charged. Regardless of what your saying the high side going sky high right when the sight glass clears means too much Freon. Some of these systems are real touchy on this. A tenth of a lbs. can be the difference.

2) The lesser brands of tractors do not have good parts support. The Montana tractors have been made by several manufactures and under several brand names. Parts support and dealer support is spotty at the best.

Can it be brazed shut? I fixed a lot of condensers on older Deere combines were people would open them to clean out dust and would break the end off.

Over charged will blow something apart.

This might help. Scroll to FIG. 10-9
http://partsformontanatractors.com/files/Montana_Parts_5740.pdf

Well I was going to look at the parts description, but the download was over 300 pages and I pay by the gigabyte so no joy. These tractors were produced in 2005 so they came using refrigerant A134.

Depending on the dimensions it is sometimes possible to fit another make of condenser to your tractor and there are adapter fittings available to help do this. It all depends on the evaporator. Just guessing. Is this condenser one of the parallel type which are usually very thin or is it a serpentine type where the tube is one continuous serial type which are usually larger and more stout?

As others have said possible overcharge.Also high head pressure is caused by poor air flow thru the condenser-either the fan not turning or turning too slow,stopped up fins,something blocking the grill.Not as likely would be a restriction BEFORE the expansion valve.If it has a drier and expansion valve,maybe the drier.If has an orifice tube and accumulator,maybe a clogged line.The whole system may require a flush.Mark

Measure it and see if there's something else that would fit. It will likely be difficult to source the OE part.
You say the system wasn't overcharged, but by the sounds of it, you were trying to charge it based off of the sight glass, which doesn't work with R134A. You can charge it with pressures and a chart, but you need a proper gauge set for that. There should have been a high pressure safety switch, unless you bypassed it to force it to run. The expansion valve(TXV) won't cause this either, because in a properly charged system, if the TXV is plugged, and no refrigerant passes through it, the low side will go into vacuum, which will turn the pump off with the low pressure switch, Even if it didn't turn the pump off, the pump will have nothing left to pump, and pressure will level off. If it was overcharged, and the TXV was plugged, or even if it wasn't, the high side pressure would keep on climbing as long as the pump was on.

dale r,
It looks like the tractor was brought to you with the AC not working is this correct?
I presume you vacuumed the system before you charged it or did it still have some R134A in it?

Do you have any pics of the condenser?

I think that the tractor was made LS a division of Hyundai and later LS merged? was bought? etc. and sold tractors through LS Montana, Farmtrac, Longtrac and various other entities. I don't have a list of the ones similar to yours, but it is possible that some of the A/C systems used similar condensers.

For instance, there was an LS model called the LS Neo N60. This tractor has the same Mitsubishi engine as the 5740 and it weighs almost the same and looks the same except for the color scheme.

Going by your description of the problem, it appears that it was indeed overcharged.
If this was designed as a 134a system, it should have a low and a high pressure switch. The low pressure switch prevents the system from operating if the charge is too low. The high pressure switch keeps the head pressure from going too high. This is because a 134a system will go very high very quickly under some conditions.
Not likely to be able to braze or otherwise repair the condenser since it is made of aluminum.
As others have said, the sight glass is not to be used for charging.

There are several things that will cause a system to have poor performance. Low charge is probably the most common. Overcharge will also cause a lack of cooling. The refrigerant needs to have room to expand when it changes state to gas in the evaporator. Another possible cause is too much oil in the system. Excess oil takes up the space that the refrigerant needs to go from liquid to gas to liquid as it goes through the system. A bad expansion valve commonly leads to overcharging. Start out with poor cooling performance which leads to adding refrigerant which leads to overcharging. Another possible problem is air in the system. A refrigeration system works by the refrigerant changing states from gas to liquid and back to gas over and over. Air is not compressible to a liquid in this environment so it will interfere with the operation of the system. Moisture is another possible cause of poor performance. It is very important to evacuate the system before attempting to recharge it. This is to remove the moisture and air in the system. And, every time a system is opened, it WILL get air and moisture into it. This can only be properly removed with a good vacuum pump. Failure to evacuate usually results in poor performance and early failure of compressors and expansion valves.

you might check with apairinc.com 800-806-5312 i don't see your tractor listed but i have sent them one off a tractor abd thy built me one be worth a try

Ran the part # and found this. Grab holt yer shorts.
http://store.montana-tractors.com/a1865081.html