Dustin Sayer
Member
I have replaced orifice tube, drier, cleaned out evaporator and condenser. new filters vacuumed out system and new refringent still cant get the vent temp to go below 60 degrees
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Cat D4XL AC help
- Thread starter Dustin Sayer
- Start date
Dustin-
Would be more than happy to advise, please respond with the following information.
-Machine serial number prefix
-AC pressures (high side and low side) at idle and high idle
-Ambient air temperature
-A little bit of history leading up to this issue
-How much R134a was put in the system during recharge
Would be more than happy to advise, please respond with the following information.
-Machine serial number prefix
-AC pressures (high side and low side) at idle and high idle
-Ambient air temperature
-A little bit of history leading up to this issue
-How much R134a was put in the system during recharge
Dustin Sayer
Member
Hello and thank you. the ser number prefix is kmm
low side pressure is 50 at idle high side is 250. I have not checked at high idle
ambient temp 90 degrees
the ac would blow cold in the morning when the ambient temp is around 70 degrees, but once it got past 80 outside the vent temp would be lucky to get below 70, so i put new filters in cleaned the condenser and evaporator. Both fans are working, Compressor is working and still the same results. So I replaced the drier and orifice tube, vacuum out the system and added 3lbs of freon. Now vent temp is a consistent 60 degrees so it's a bit better but I checked vent temp of our other machine's (one being same model and year dozer) all are blowing between 40 and 45 degrees out the vent
heymccall
Senior Member
Where'd the 3# spec come from?
The pressures and the "3#" sound very high.
The pressures and the "3#" sound very high.
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Spec is 2.9Lb per sis web.
Dustin Sayer
Member
call cat and thats what they told me
Mark250
Senior Member
- Joined
- Aug 30, 2015
- Messages
- 1,243
- Location
- victoria,Australia
- Occupation
- heavy equipment technician
check that the heater control is working correctly
turn off the heater taps on the engine to confirm
turn off the heater taps on the engine to confirm
Dustin Sayer
Member
ill look into this. do you know where the taps are located?
CM1995
Administrator
- Joined
- Jan 21, 2007
- Messages
- 13,375
- Location
- Alabama
- Occupation
- Running what I brung and taking what I win
I really have nothing to offer in this discussion except it makes a big difference in the A/C with the heater valves off on our D5G and 953C. Sometimes I'll forget to turn the valves off when the weather turns warm and think we have an A/C problem.
Dustin Sayer
Member
Blend door seems to be working fine
heymccall
Senior Member
I, personally, think the charge level is too high.
I just replaced a compressor on a 314ELCR, and the machine sticker for charge amount was different than the book. The book was higher.
I'd like to see no more than 40 psi on the low side, at idle, on an 80° day. At fast idle, when I don't have a charge spec, I try to make sure it doesn't drop below 25psi on the low side.
All of my late model Cats do have a charge amount sticker somewhere on them.
Any chance of throwing the gauges on the twin machine you have?
I just replaced a compressor on a 314ELCR, and the machine sticker for charge amount was different than the book. The book was higher.
I'd like to see no more than 40 psi on the low side, at idle, on an 80° day. At fast idle, when I don't have a charge spec, I try to make sure it doesn't drop below 25psi on the low side.
All of my late model Cats do have a charge amount sticker somewhere on them.
Any chance of throwing the gauges on the twin machine you have?
Nige
Senior Member
As ahart mentioned above there are no heater shutoff valves I can see on your machine, just two spigots for the heater line connections. See illustrations below. however I suggest that you check those locations physically just to make certain.
However as a test why not try crimping one or other of the heater lines from the connections at the engine to the cab using a pair of vice grips. That will stop the flow of hot coolant from the engine totally. If the A/C then performs correctly you should start looking at the operation of the electric heater valve located in the heater assembly as mentioned by Mark250 in Post #7 above.
However as a test why not try crimping one or other of the heater lines from the connections at the engine to the cab using a pair of vice grips. That will stop the flow of hot coolant from the engine totally. If the A/C then performs correctly you should start looking at the operation of the electric heater valve located in the heater assembly as mentioned by Mark250 in Post #7 above.
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heymccall
Senior Member
50psi on the low side will never cool sufficiently.
Dustin Sayer
Member
Off
idle
High idle
idle
High idleDustin Sayer
Member
42 in the morning after lunch 72-75
1466IH
Senior Member
Does that machine have the condenser on back of cab like a track loader. Have seen lots of 953,63, & 73's with bad fans cause lots of issues.