A/C Diagnostic help

[Mogman]

It is 5/8" ID hose

 

[Tiwaz]

does that make it a 3/4 OD...? or even 1"...?

 

[Mogman]

I would think pretty close to 7/8"

 

[thoner7]

I’m pretty sure there are clamps there already. Holding in the valve that went bad.

 

[Tiwaz]

ok so just to let other people know: After installing the valve depicted in Post #58 in line, WHAT A DIFFERENCE !

 

[thoner7]

I received my valve in the mail. Is it normal for the thing to go past its “full open” and then restrict flow again?
One pic is the max open the valve will actually be. Other pick (less daylight) is when the lever is all the way to open

 

[Tiwaz]

I noticed something very similar to that on mine too.

 

[Thunderbirds]

I received my valve in the mail. Is it normal for the thing to go past its “full open” and then restrict flow again?
One pic is the max open the valve will actually be. Other pick (less daylight) is when the lever is all the way to open

I think it is normal since the push pull cable will only activate the valve a 1/4 turn. Some have a "stop" detent built into the valve, but most do not.

 

[Tiwaz]

I must say: SUBSTANTIAL IMPROVEMENT in the A/C temperature after installing the valve, also I have to say that previously I had disconnected the servo and manually pushed the little lever all the way forward but realize that it DID not slide all the way even gently forced with players, (sometimes that valve gets stuck).

 

[thoner7]

I installed my valve. No cable yet. But it seems to let fluid through, even when shut. I stupidly ordered thenone

At idle, My front ac is only cool while the rear unit is cold.

with any rpm the front begins to heat up real quick while the rear stays cold.

so I’m guessing it’s a bad valve or maybe I installed it backwards??

 

[DREDnot]

I have my original metal cable actuated valve and kept it while I retrofitted my truck to the latest AC system. Just got it charged up today and it blows cold. I checked the valve visually before reinstalling it and after installing it I function tested it to see if it fully blocked hot water flow to the heater core. It has a large range of motion and needs to be fully counterclockwise against the "stop" to be fully closed

 

[Tiwaz]

I installed my valve. No cable yet. But it seems to let fluid through, even when shut. I stupidly ordered thenone

At idle, My front ac is only cool while the rear unit is cold.

with any rpm the front begins to heat up real quick while the rear stays cold.

so I’m guessing it’s a bad valve or maybe I installed it backwards??

If the valve is like the one depicted in #66, there is no right/wrong way to install it, that is the one I have and it either stop the flow or lets it through.... (or anywhere in between) regardless of the "Direction" you installed it in.

 

[thoner7]

It’s the value in my post 66. Maybe it needs to be banded all the way closed? Idk- but as is it doesn’t work. Bought it from rock auto.

 

[DREDnot]

That valve should be turned 180 degrees and mounted on the heater side of that elbow to be oriented properly and to accept the cable correctly. The coolant to the valve/heater should be coming from the crossover assembly (that has the thermostat housing). The coolant from the heater returns to the water pump

 

[DREDnot]

Adjustment is done while the cable knob is pushed in. Slide cable sheath to the left till the arm hits the lower side of the stop. Tighten clamp. Now when you pull the heat knob out it will open the water valve till it hits the upper side of the stop. Notice the "OFF" and "ON" lettering on this original valve.

 

[thoner7]

That valve should be turned 180 degrees and mounted on the heater side of that elbow to be oriented properly and to accept the cable correctly. The coolant to the valve/heater should be coming from the crossover assembly (that has the thermostat housing). The coolant from the heater returns to the water pump

View attachment 946772

View attachment 946773

So are you saying mines on the wrong hose or on the wrong side of the elbow?

I installed it exactly where the other one was, but I’m replacing the newer electric controlled valve with the manual one.

 

[Retiredwarhorses]

So are you saying mines on the wrong hose or on the wrong side of the elbow?

I installed it exactly where the other one was, but I’m replacing the newer electric controlled valve with the manual one.

yes, its in the proper location, you just swap one valve for other…

 

[thoner7]

Well I went to Lowe’s and bought a 3/4” Pex B valve that works perfectly. So the one from rock auto I bought must be defective.
PS Pex A valves are too big. You want Pex B

 

[DREDnot]

So are you saying mines on the wrong hose or on the wrong side of the elbow?

Your location was where the original electric valve was. Fine spot for the actuating wire to reach it but not ideal if you were going to use the cable actuated unit. Then you would need to mount it as in my pics. Your placement is probably best for using the manual handle you went with.

 

[thoner7]

So the last issue I am having with my AC, may not be an issue at all. It pertains to the rear evaporator like in the 1165 and 1151.

It will randomly shut off(stop blowing air) and then start back up again 30 seconds, a minute, some short time later. The front evaporator blows as normal during this time. Also, the rear evaporator doesn’t seem to have a high/low setting like the front. It just blows in what I assume would be high, the whole time.

maybe both of those are normal? I wouldn’t know. Or maybe it’s a safety shutoff for some reason.

if anyone with more knowledge of these trucks could chime in, I’m always very thankful.