A/C System Help!!!

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jfkelley

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have an 1976 K10 Scottsdale 4X4, The A/C has been retrofitted it blows Semi Cold when Idling , But if I give it gas while sitting still the blower speeds up and blows cold, Also when you drive it you can hear it start blowing harder and its gets cold..A/C has been charged , All Ducts been inspected and are good..Do I need a new Clutch fan or Blower Motor ? Maybe one out of an 1994 Truck?..Plus the A/C Blows Max regardless what setting you have it on...Its HOT in Oklahoma Everyday way over in the 100’s today...Any Help or Advice would help ...Thanks !
 

HotRodPC

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Sounds like you might have more of a voltage issue. If the blower speeds up when you rev the engine, your voltage may be dropping at idle. By retrofit, do you mean converted to R134A freon? That might be part of the problem too. From what I hear, the R134a requires a higher pressure and maybe the compessor isn't putting that higher pressure out at lower rpms.
 

HotRodPC

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What rpm are you idling at? Auto or manual trans? Maybe bump the idle up a 100-200rpm for the summer. If you're at 500 rpm now, 700 won't be to bad.
 

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Make sure the condensor isn't obstructed with dirt, etc. and is able to flow fresh air across the fins.
 

jfkelley

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I have an 1976 K10 Scottsdale 4X4, The A/C has been retrofitted it blows Semi Cold when Idling , But if I give it gas while sitting still the blower speeds up and blows cold, Also when you drive it you can hear it start blowing harder and its gets colder..A/C has been charged , All Ducts been inspected and are good..Do I need a new Clutch fan or Blower Motor ? Maybe one out of an 1994 Truck?..Plus the A/C Blows Max regardless what setting you have it on low medium ..Its HOT in Oklahoma right now 118 today...Any Help or Advice would help ...Thanks !
 

dvdswan

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To test your fan clutch, engine off, cold, and depending what the temp is outside (i.e. below 40* or above 100* the fan should turn with good resistance). Engine off and the engine is warmed up and 118* outside the fan should not turn at all.
 

HotRodPC

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Make sure the condensor isn't obstructed with dirt, etc. and is able to flow fresh air across the fins.
Yes, that too.
 

Rusty Nail

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Sounds like you might have more of a voltage issue. If the blower speeds up when you rev the engine, your voltage may be dropping at idle. By retrofit, do you mean converted to R134A freon? That might be part of the problem too. From what I hear, the R134a requires a higher pressure and maybe the compessor isn't putting that higher pressure out at lower rpms.

My thought substituted VACUUM for Hotrod's voltage issue. Increased engine speed reduces available inches of travel? Some ****. Is it blowing equally side to side or?

$525+or- to fix mine. That's the bar cuz I was seein about mine yesterday. :(
How much YOU got to spend? lol? Hot AF! :flamingdevil:
 

jfkelley

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Thanks for all the replies ..No Baseball tourney this weekend , So I will try everyone suggestions & report back my findings
 

jfkelley

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Sounds like you might have more of a voltage issue. If the blower speeds up when you rev the engine, your voltage may be dropping at idle. By retrofit, do you mean converted to R134A freon? That might be part of the problem too. From what I hear, the R134a requires a higher pressure and maybe the compessor isn't putting that higher pressure out at lower rpms.


Yes sir I was meaning R134A
 

jfkelley

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I took a video of the AC Compressor with A/C going Belt flopping around

1st pic is at Idle with A/C on
2nd Pic is driving with A/C on

You must be registered for see images attach


You must be registered for see images attach
 

jfkelley

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Please check your grounds as well including the battery posts. Bad ones can cause those symptoms
Please check your grounds as well including the battery posts. Bad ones can cause those symptoms


Check all the grounds I could find and cleaned them with wire brush and reinstalled and no change in AC ..Do I need a Bigger Alternator ?
 

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