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247b Needs Help

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What year is your 247b? Mine is a B2 series (2007) and there is no power loss when I use the A/C as it is run with electric motors, just electricity from the alternator is required. You might have a clogged fuel filter.

I have a little experience with the 247, and lots of experience with pump failure! If I was you, I would stop running it right now. First thing you should do is check the cooling fan speed. I have a feeling the fan is turning too slow. So to do that, you and a buddy should start the thing and check how fast the fan is spinning. Should be around the speed of an electric fan of a car or just slower. If its turning too slow, you'll need to buy a pressure gauge, hose, and a quick connect setup that threads into the housing of the hydrostatic pump, and check your "charge pressure". Charge pressure is very important, if its too low you will destroy your hydrostatic pump, and that is a $3000 dollar kiss you don't want. Charge pressure should be 450PSI give or take 20PSI. The charge pump controls all work tool movement, cooling fan, and oil supply to the hydrostatic pump. The hydrostatic pump controls the drive function of the machine. The drive pressure is 5600PSI, so be careful not to test the wrong port. If you don't have a service manual now is a good time. Best $500 bucks I ever spent. Let us know what you found and I'll try to post some pictures of my pressure tap locations. Oh, and don't buy a gauge that will read 6000PSI to test a 450 pound port. A gauge isn't accurate until 60% of its capacity.

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Thank you for your response. I'm not dumb, but I'm not a mechanic so stay with me. The fan speed seems to be fine by visual inspection. Is pump failure common with a 2006 247B? I grew up with Case wheeled machines and am new to Cat and tracks. It's been a learning curve, and not a good one. I had to run some Napa universal hydraulic oil, do you think this might be some of the problem? As far as moving the machine, everything is fine until the A/C is on, nothing else affects it. I was thinking maybe something in the valve body. Where did you find your shop manual? Thanks again, Lost

The cooling fan speed can be turned up, there is a jamb nut and threaded shaft on the motor just below the in/out hoses. Loosen the nut and stick an Allen key into the shaft and turn it so the fan speeds up and tighten the nut again, holding the thread shaft still while tightening. I wonder if Cat switched from a belt-driven A/C compressor to the new style they have now in 2007, the B2 series? If so, it's got to be the compressor.

I'm sorry, I don't think I'll be much help. My manual doesn't have any info on different years of tractors. My a/c runs off a belt from the motor, just like a car. Is your a/c compressor run off something different? I don't think pump failures are too common with Cat. but I bought mine with a failure just around the corner. After rebuilding the pump I was very worried about the oil to use. I searched the internet for a week and thought that the CAT. "HYDO" was the only safe option. So I went to the local cat store and the parts guy there said that my machine used regular hydraulic oil "AW22". So I bought it from my local parts supplier. I would have used NAPA but they were too expensive. When I got the oil delivered I read the label and it stated it passed the Vickers 35VQ25 test. Apparently this is an important test. My cat has run good ever since. I bought my service manual at the local cat store and a parts manual. Together they were $509 Canadian, so you might get it cheaper? Sorry I'm not much help, but I would like to know the problem when you find it.

If you have an A/C run off the engine with a belt, then the A/C pump is shot, that's the problem you are having with the slowdown, even if the cold air isn't as cold as it used to be is a warning sign. If it was hydraulic causing the issue, it would have done something really bad a long time ago. The current B series have an electric motor that runs the whole A/C show, no more belts.

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