I have a cat 314 that the climate control system and the AC compressor function but there is no air coming out of the vents on any setting. Is there any kind of procedure out there from the cat to diagnose this issue? If not, does anyone have a wiring diagram for this machine? Machine Serial# PCA00905
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Blower motor itself most likely failed. It's under the seat pedestal.
207-0112 $640 from Caterpillar APAIR is where I got mine. Remove seat. Remove floor mat. Remove pedestal. Remove all phillips screws above blower motor. Remove shell. Replace blower.
Is removing the seat pedestal relatively easy or is it a job? I don't have to take out the left and right consoles or anything right?
It is a total PITA. Position the machine so that you can stand on the track directly in front of the cab. Seat comes out easy as does the floor mat. I also remove the lower windshield and the travel levers and pedals. The pedestal needs unbolted from the floor pan, but, the pedestal has the suspension and armrests. Its been a little while since I did one, but, I support the suspension and armrest assembly upward with two ratchet binders attached to the door hinge (upper) and, iirc, a coat hook in the rear corner, after separating from the pedestal. Both my 314CLCR & 321CLCR are the same, and I've done them both. The hvac box, fortunately, has a two piece upper housing, and only the cover above the blower motor needs removed. Perhaps someone on here can dig up the Cat instructions?
Mind you, the above is for a 308C, but, it all looks right.
That looks like one hell of a job
5 hours the first time (my 321clcr) 3 hours the second time (my 314clcr) Dirt accumulated over side duct bolts and rear pedestal bolts impede quite a bit.
Do you remember if that is the power for the blower motor? Because with my multimeter I'm only getting .7 volts to it no matter what fan speed I set it too. Hmmmmm
^
#8 is blower resistor (control assy in caterpillarese) 229-9139
You can always apply 24v (or even 12v) directly to the blower to test it.
Blower motor turned on when we applied 12v to it so it's not getting power from the other side of the plug. Any idea where that runs to?
My gut says to check all fuses. IIRC, I had to replace fuse panel on my 314CLCR for rot. Made rain shield and cover for replacement one. I think we need schematic now. That I don't currently have access to.
Fuse #1
We've done that procedure to replace the blower motor on our 321DL - not fun, not fun at all. Thanks for sharing the knowledge and instructions HYM.
Well I am very embarrassed to admit that it was fuse #1 LOL. Now I just have a problem of something squealing if I turn the compressor on
That one's easier. AC compressor is on its own dedicated belt. Belt has idler pulley with jack screw. Remove cover under belt drive end of engine. Reach up and check belt tension (engine off, of course). To adjust, loosen nut in middle of idler pulley by 1/2-3/4 of a turn (17or19mm wrench). Then turn jack screw (12mm) CW until suitable tension is achieved. Tighten pulley nut. But, not only check tension, but also belt condition, and, most importantly, spin idler pulley, listening for noise or rumble. The bearing is a 620S on most, and can also be purchased as a bearing only from Caterpillar. Just pressed in and snap ringed. In my experience, the belt needs tightened every other oil change, and the bearing, every 5-7k hours.
No you're lucky if that's all it was. I'm no mechanic but check the obvious - A/C belt and tensioner. ON EDIT - Ha HYM beat me to a post by a few seconds.
Why would I have to loosen the pulley in order to tighten the belt with the jack screw?
Because I said so Well, that, and that's how Mitsubishi designed it.
Alright well thank you for all your help I greatly appreciate it
I've seen lots of those compressors frozen up on Cat excavators. That might be a possibility as to why the fuse was blown and that belt is squealing. The other problem I've seen lots of is the area around the blower packed with dirt and debris from the filters not being changed from time to time. The squirrel cages get locked up and then blow the fuses or burn out the motor. I think heymccall means to loosen the pulley mount bolts so it can move in the slots as you adjust the screw to tighten the belt. The screw only pulls the wheel, the mount bolts hold the wheel in place.
I must have really good luck because all I had to do is tighten the belt on the compressor and it stopped squealing and the AC blows ice cold now. I'm happy