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quick question on cold a/c mod

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Old 06-08-2017, 01:59 PM
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quick question on cold a/c mod

I got the ranger valve installed and ran the vacuum line into the cab (replaced my water pump and radiator so did this mod while I was at it). Do I have to pull any panels off in the cab to get to the vacuum actuator to tee the vacuum line into? I don't see the same actuator easily accessible like I see in all the pics. I haven't pulled any panels/covers from the front as the write-ups I was using didn't say to pull them. What am I missing?
 
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Old 06-08-2017, 03:23 PM
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I could get access to the connector inside the cab if I were a contortionist, but I am not. I found it quite easy to get access to by removing the glove box, which is a very simple task.

If you cannot find it that way, try and locate the white vacuum line and follow it back toward the middle of the dash in reference to the stereo and A/C controls. If you still cannot find it, post some pictures and we might be able to help you locate it.
 
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Old 06-08-2017, 03:28 PM
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Funny, I bought the parts for this years back and still haven't done this yet. Seems I'll be doing it this year. Question, on the clutch, when I remove this dose it loose freon? I did the spacer two years ago but now it seem to cycle every once and a while. It has freon so that's not the problem. I know Tim just did his, maybe I should PM him.
 
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Old 06-08-2017, 03:30 PM
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Bonanza35, no need to remove the compressor clutch for the max a/c mod. Unless of course your clutch shims need to be adjusted.

Either way, the system does not lose freon when the clutch is removed.
 
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Old 06-08-2017, 04:49 PM
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I did the adjustment already. I could replace just the plate part but I thought I mitt as well do the hole clutch. I know I don't have to do the clutch for the above mod, I just want to make the air work better without changing the compressor if possible. The gap was to open when I did it the first time. It only had one shim in there so when I removed it, it worked fine. It's been two years now and it seems to be doing the same thing again. And I should do the mod at the same time being I've had the parts for years.
 
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Old 06-08-2017, 05:51 PM
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Won't lose anything Chet, but if you do replace everything, be careful on removing the pressed fit backplate thats secured onto the flange of the housing....ad for the ranger valve, if I leave mine on anything but "both settings", it'll retain pressure and leak...weird
 
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Old 06-09-2017, 12:46 PM
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Thanks Tim. I've had that valve for years. Robin first bought that valve up I believe. I think he said the red line works best. I bought this valve from Ford. It was cheap really.
But never installed it.
 
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Old 06-14-2017, 11:10 AM
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Okay, I was able to locate the valve I needed to tap into. It was located pretty close to the intake vent...was thinking it was more behind the control panel so was just looking in the wrong spot.

I did some experimenting yesterday with the temperature drop by engaging the bypass valve. I was running on Max A/C with the windows down to let the cabin be same temp as ambient air. I thought this should better measure the true temp drop across the coil then when using Normal A/C vs. Max. Since in Normal, it's pulling ambient air from outside, I wanted to also pull in ambient temp in Max for a direct comparison. In short, I got a 5F degree drop when bouncing from normal to max so definitely worth the few minutes of trouble to install. Went from ~55 deg to ~50 so not bad.

But on the flip side, the system will randomly go down to 40 degs for a bit and even bounce up to 60 degs for a bit during a long stretch with no differences in driving conditions. So, I probably need to adjust the clutch or maybe even replace the expansion valve. Just one more thing to do...when I have time and patience
 
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Old 06-14-2017, 11:54 AM
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With your system cycling as you describe, it sounds (to me) like the air gap on your clutch is too wide. If you have any remaining clutch shims in place, you might be able to remove some or all of them and regain steady performance.

Also, just getting down to 50°F is not extremely sporty at all. When I did mine some 6-7 years ago, it went down from 55°F to 42°F, and will even still hit 40°F or below in the cooler seasons, and I've put over 100K miles on the truck since the shim removal and Ranger valve mod. You may be a either tad light OR a tad heavy on Freon (added any recently?), or you may actually have a bad proportioning valve.

Still, I would work on the clutch air gap issue first as it's the cheapest route to take from where you are (unless you have excess Freon and can simply bleed off any excess).
 
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Old 06-19-2017, 08:24 AM
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This weekend I found some time to pull the center bolt in the a/c clutch to remove a shim but there were no shims to remove. Hmmm....not what I was hoping to find. What's the air gap supposed to be between clutch/pulley?

So before I go assuming I need a new clutch/compressor/etc., I'll double check my freon pressures. I added a couple cans about a month ago to get my low pressure above 50 but the second can took it above 65/300psi (lo/hi) so I recovered one can's worth of freon. Haven't played with these pressures yet. Assuming 95 ambient with 40% humidity (standard this time of year in Austin), what pressures should I get at 2000 rpm? Does it matter if 2k rpm or 700rpm at idle? Trying to understand if I have worn reed valves in the compressor or gunked up expansion valve or something else. Since I bought the truck with 220K on it, who knows what's in the a/c system...
 

Last edited by LCA078; 06-19-2017 at 08:30 AM. Reason: added question about air gap
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