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Gap should be between .014" and .030", give or take a bit. Once the gap gets too wide, the clutch becomes flaky.
ok I’m going to try to upload a pic if someone can weigh in. After attaching guages my clutch would cycle on and off so I watched my guages as it would do it (low side) when the clutch would kick on it would be about 40 psi and when the clutch kicked off it was right at 20 so I did a little further investigation and it says the low pressure switch cuts the clutch off at 20 psi so I added some 134a my truck holds 33 oz I believe. anyways I added enough to get it to 25 psi and my clutch stayed engaged and I felt my ac in my truck and it was getting cooler. At the time the outside temp was about 75 degrees so I charged the system to 45 low and 150 high 2 cans 24 oz and my ac was nice and cold and I was happy.. so I unhooked everything shut the truck off waited about 10 mins started it again turned ac to max and clutch isint engaging FML I was happy. It seems like when the truck is nice and hot (warmed up to operating temp) my clutch won’t engage seems like my clutch engages when I first start my truck in the morning but today is the only time it’s been cold after adding refrigerant.
I’ll be measuring the clutch after the truck cools down it does like wider then a business card
ok I’m going to try to upload a pic if someone can weigh in. After attaching guages my clutch would cycle on and off so I watched my guages as it would do it (low side) when the clutch would kick on it would be about 40 psi and when the clutch kicked off it was right at 20 so I did a little further investigation and it says the low pressure switch cuts the clutch off at 20 psi so I added some 134a my truck holds 33 oz I believe. anyways I added enough to get it to 25 psi and my clutch stayed engaged and I felt my ac in my truck and it was getting cooler. At the time the outside temp was about 75 degrees so I charged the system to 45 low and 150 high 2 cans 24 oz and my ac was nice and cold and I was happy.. so I unhooked everything shut the truck off waited about 10 mins started it again turned ac to max and clutch isint engaging FML I was happy. It seems like when the truck is nice and hot (warmed up to operating temp) my clutch won’t engage seems like my clutch engages when I first start my truck in the morning but today is the only time it’s been cold after adding refrigerant.
I’ll be measuring the clutch after the truck cools down it does like wider then a business card
so my biggest feeler guage I have is 0.35 and it slides right in with enough room for maybe a business card is this gap too big to cause clutch to be acting weird? Can I tighten the bolt in the center of the clutch to make the gap slightly smaller or do I have to remove a shim?
That's too wide, you have to remove shims to adjust it. Ideal is .020". You might have to replace the clutch, it may be excessively worn.
okay 2 things out of curiosity can shims be removed without removing the belt and why does the clutch engage when the engine is cool but not after the engine warms up?
True, but an experienced AC guy can use a gauge set to get it close enough. The charge doesn't have to be exact for the system to work just fine. I've been charging my auto and home AC units for 50 years.
I wish it were still that simple. Yeah, it'll work okayish on some units, others, no. I worked with some geothermal Climate Master units a few years back. The charge had to be dead on accurate or they would shut the compressor down. I think it was a little over 3 pounds of 410a. I can usually charge 410a just by holding the liquid line, though I still verify it with a scale or by measuring superheat.
Newer package systems aren't as tolerant as older units of any kind. New units are picky, older systems are like, "you just dropped an engine on me. Who cares?"
Last edited by shadow460; Jun 19, 2021 at 11:07 PM.
I wish it were still that simple. Yeah, it'll work okayish on some units, others, no. I worked with some geothermal Climate Master units a few years back. The charge had to be dead on accurate or they would shut the compressor down. I think it was a little over 3 pounds of 410a. I can usually charge 410a just by holding the liquid line, though I still verify it with a scale or by measuring superheat.
Newer package systems aren't as tolerant as older units of any kind. New units are picky, older systems are like, "you just dropped an engine on me. Who cares?"
One more reason to keep my old reliable truck. The AC in it had a slow leak and it would work with widely varying amounts of refrigerant. I finally found the leak at the compressor connection and put a can of refrigerant with the leak stuff in it and it doesn't leak any more.
My home heat pumps use the 410A. That's interesting. And they work with varying amounts of refrigerant too. After 9 years one quit working because of low refrigerant and the evaporator was replaced. Parts had a 10 yr warranty. Then the other quit working after the warranty. I got hold of some 410a and charged it a couple of years ago and it is still working. My heat pumps have the same connections as cars with R12 so my old gauges worked.
