I have a 289C and the ac isn't blowing cold. My mechanic friend recycled and replaced the Freon to the correct specs on the tag. The compressor is engaging off and on with the switch. I'm thinking it's some sort of blending switch that swaps it from hot to cold. He said the low side line was cold. The heat works fine. Is there a fuse I need to check and if so where would it's location be since this one has a few? Anybody have this issue before that can help?
How cold is it where you are? If its very cold the low pressure switch is probably not letting the compressor run. Or there is an ambient temp switch not letting it work.
It may be that the heater valve is not shutting off the flow of hot coolant to the heater. Cat has had some problems with the valves not sealing off completely. This will cut down the ac efficiency. Check the heater hoses at the engine. Or as close to the heater as you can. They should both be fairly cool if there is no flow. If there are shutoff taps on the engine for the heater hoses shut them off temporarily.
Move north, it almost hit 10* today. The fuse for the A/C condensor fans blows a lot, 20 amp fuse inside cab. Check that and make sure the condensor is clean, its a PITA to clean on those machines. The heater valves cause issues also, if coolant is running through the core you will never get heat. The valve is attached to core, have to lift cab and remove plate that covers cores to get to it. Clean out heater core and A/C evaporator while there as well, it will help a lot. Cat doesn't list the heater valve seperate IIRC or they get a lot of money for it, but its a red dot part and you can get it through red dot dealers for less than $100. It's an electric valve. You can always just put a mechanical one back by the motor which will work better anyways.
So basically the valve is something that prevents flow thru the motor? If you have or can take a pic of what I need to look for or the valve itself and post it that would help out a lot. I assume that is what works when you slide the knob from hot to cold? I'm sure it'll be highly visible if not, I'm not a mechanic but I know my way around a engine. If you have access to a manual one that has been put on an engine also I would like to see it. Just weighing options so I can take the best route. And when u say red dot is that the name of the website I can get the part from? We've been having a spike of bad weather lately so I plan on trying to knock all of this out when we have another nice warm day
Where would or what side/area would I look for the heater hoses if I'm facing the engine from the rear?
I've had the issue since Summer so it was hot at the time. No need to run the air this time of year but I just want to get a jump on it before the warm weather comes back around.
You're not going to see a lot if you are looking at the engine compartment from the rear. The heater is buried under the floor of the machine and as posted previously you will need to first raise the cab then lift the floor plates in order to even get at it. The first illustration shows the heater lines, the second shows the heater assembly itself. The valve that controls the coolant flow is #7 at the bottom LH side of the illustration - the RH side as the heater sits in the machine.
Ok it took me looking at it a couple of times to understand it. So the one to the right is the actual plate that I have to lift and I should be able to have access directly to it like that? Also on what number or close to it on the right one do u think there is a shut off because that looks like it's behind the seat without easy access? And does that assembly with the valve attached to it just come out of that box completely?
Have you had the cab up on your machine? The right picture with the "A" and "B" is under the cab in front of the drive motors, nothing behind seat. Its not even attached to the cab, it seperates when you lift the cab on the C series. Flip the cab up first. Then you will need a Torx (want to say a T30) and a 10mm to remove number 11 and then number 3. 11 holds the HVAC up off the base of machine, 3 is the cover. The heater valve is on the right side of the machine between chaincase and HVAC box where coolant lines come into HVAC box. This is what you will see with cab up, (on a 262C2 machine though) red arrow is pointing to the plate you need to remove. Yellow circle is approximate area of valve, its not visible in this picture. The pink arrow is the air inlet and the blue one is the air to the cab. Keep debris out of these when cleaning. Here's another picture, yellow arrow is HVAC box that sits in belly, blue arrow is plate, red circle is blowers, green arrows point to Evap and Heater core.
Make sure the gaskets where it all mates are good. A lot of air loss and dirt intrusion happens there. Did yall float that machine dually?
Float it? As in loose it in the drink? Nope, that's just how it looks under there after a couple months. That machine does all of the bedding with a side shooter so a lot of dust gets everywhere. Traded it for a 262D last year and they stay much cleaner, still collects a lot of junk but not near as much.
Ok those pics were very informative and now I know exactly what to look for. I have had it up once to fill hydro fluid and redo the freon but didn't really pay much attention to anything else, looks exactly like mine tho if I remember correctly. I'm gonna get me some torx tools to have them ready, I think I'll be able to pop it up tomorrow and see what I'm working with. First off I guess I should allow the machine to run for say 15 minutes to allow it to warm up to check the temp of those 2 lines right? You also said that if coolant is running thru the core I wouldn't get heat but not having ac is my issue. I'm going to check that 20 amp fuse also before that process.
Ok I just checked the fuse and that was good so I'll go on to the under cab method next tomorrow. Some thing I noticed also that I wasn't sure I shared but its pretty much blowing hot in ac mode. I found that to be strange cause I know that it should be lukewarm at best even if the Freon is low. Sounding more like you said about that valve not opening to allow the coolant to flow properly as the cause?
The problem is actually the heater valve not closing completely and keeping the heat on. I think this was a missprint in a previous post that is confusing. You definitely want to stop all heater coolant flow to get the best ac.
Yeah I typed that wrong, haven't thought about A/Cool awhile. If coolant is flowing through heater core you will not get any cold air. Do you have a hose pinch tool? Pinch one of the heater lines off and see if the AC starts to work.
Ok I'm just now believe it or not getting enough time to fool with this thing. I took pics of it while it's broke down since mine looks a lil different than the pics u posted. I see there is a red and blue hose near where u were talking about and I was wondering if this was the lines u were talking about closing off? Let me know if these are good and if I need to take a pic of something else. Also show me that part you were talking about I need to replace. And where could I put a shut off valve if all else fails?
I'm messing up with trying to post these pics
Ok I think my problem is the valve because the line I'm pointing at is ice cold and sweating. The other hose at the top is hot and the one on the bottom is very hot and I can feel the fluid flowing thru it so I'm sure it's not cut off. My question now is which hose do I need to splice and put a valve on? Also is there a specific type or style of valve you recommend or prefer?
Don't have an older C/C2 machine anymore to show you the part. I believe it may be Cat P/N 328-3317. I know it says the red dot part number right on it though and was only $90 through them. You can splice in a simple ball valve to stop the coolant flow to heater core. This was the standard for many many years.
Yea I think I'm going to try the ball joint method. I got one today and after talking to Cat here locally he said I could put in on either of the hoses under the plate or the one that runs to the thermostat housing. Is that correct?
I'd put it in the engine compartment so its easy to get to especially if you have some big weather fluctuations like we see to here, you will want to be able to turn it on and off easily. If I am seeing things right and remember correctly, you can just thread the 90* adapter out of the thermostat housing and thread a valve like this in, then attach hose to it. Probably the best way to do it, then you don't have to worry about supporting the weight of the ball valve. Not a huge deal if you just splice in the valve though either.
That's exactly what I'm looking for. Where did you get that set up from because I think it'll look better than what I bought for it? And I won't have to hold it stable while turning it on and off.
How much would you charge to send me those parts or where exactly can I get it from?
Here is a link, get the number for the one you need/want and look around. http://www.grainger.com/category/truck-valves/shut-off-valves/plumbing/ecatalog/N-mxv?bc=y
I put the second one in my Dodge heater lines. The valve quit working right after I replaced the dash and that was no fun!
I just wanted to thank everyone that responded to my post, it was very helpful and I now have ice cold air blowing now thanks to u guys. Much appreciated!
Proof that this is one of THE Best and Friendliest Forums, and Full of Good Folks that I have been around _ Great to hear it worked out so well!!
You'll just have to remember to open the valve in winter or your *** is gonna freeze ...... in fact you might be well advised to open & close the valve every once in a while just so that it's not seized up when you need to move it.
Lol ok good advise and I'll surely take heed to it, thanks