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Old 06-16-2018, 10:45 AM   #1
LDO
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AC Help

My 85 C10 has a 305/700R4.

The previous owner had the AC converted to R134. It cools pretty good but the compressor cycles off and on pretty regularly and the belt flaps a little even though it appears tight when I check it.

Is there a fix for this? No idea how the conversion was done or if done correctly. I suspected the freon level might be low but when I put guages on it to verify, it reads a little high when the compressor runs then drops off when it cycles off (a normal indication I would imagine).

Anyone have a fix for the compressor cycling?
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Old 06-16-2018, 03:46 PM   #2
Dead Parrot
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Re: AC Help

It is normal for the compressor to cycle when things are setup correctly. You worry when the vent air is barely cool and it isn't cycling or it comes on for a couple of seconds then goes off for a while.

What are the vent temps with the fan on high?

If yours is a V-belt setup, that long run from the compressor to the PS pump will bounce a little bit.
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Old 06-16-2018, 05:12 PM   #3
LDO
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Re: AC Help

Well, I didn't have a vent temp gauge so I ran down the road about 5 miles to the Napa to pick one up. Driving back doing about 55-60, vent temp never got down below 60F. Pulled into the driveway and popped the hood, compressor was running constantly and making a fast tapping noise, not super loud but still noticeable. I decided to call it a day, have some beers and step into Father's Day Mode.

It gets pretty hot here and with a black interior, I know there is only so much that can be done but it should be colder than that IMO.

Thanks for the advice in advance.
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Old 06-16-2018, 06:33 PM   #4
hatzie
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Re: AC Help

Around 45 degrees vent temps is normal.
Knocking... clutch or compressor?
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Old 06-16-2018, 06:36 PM   #5
LDO
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Re: AC Help

Quote:
Originally Posted by hatzie View Post
Around 45 degrees vent temps is normal.
Knocking... clutch or compressor?
seemed like it was more like a ticking noise coming from the clutch.
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Old 06-16-2018, 10:45 PM   #6
andyh1956
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Re: AC Help

LDO ride down here one weekend & we'll pop the gauges on there & see what's what!
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Old 06-17-2018, 10:40 AM   #7
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Re: AC Help

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Originally Posted by andyh1956 View Post
LDO ride down here one weekend & we'll pop the gauges on there & see what's what!
Thanks man, I appreciate the offer. You are about 2 hours from me. I'll PM you and maybe we can set something up for next week!
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