How much Freon in a SB Truck

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oneluckypops

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ok fellers, I have gotten all the A/c **** put on the truck, I got new hoses made for it yesterday and am geeting ready to go suck it down and charge it up. I have not been able to find any specs for these trucks on the internet. Does anyone know what the Freon Capacity is in these trucks? I cant remeber for sure but i was thinking it was like 3.5 pounds of R12.

Can someone verify if there tags are still readable on your trucks?
 

bucket

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IIRC, my Burbs hold 4.5, lol.

Your stuff ain't stock, I'd start with 2.5 and see what the pressure readings are. Then bump it up in small increments until the pressures are good and it's coldest out the vents.

Edit: It holds 5.25! I didn't remember it being that much. I went out to look at the '84 C10, then realized the wife took it out to go searching yard sales.
 
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skysurfer

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You going with R12 or R134?
 

oneluckypops

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you would be correct bucket, it defintly isnt stock form. I was just hoping for a Reference number from another truck. Im betting mine will be around 2 to 2 1/4 pounds.

The compressor is an HT6 which is designed for 134a freon.
 

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The factory spec is 56 ounces.

On a fully evacuated system I usually dump in four 12 oz cans. But, because the capacity was specified for R-12 - not 134a, I trickle the last one in.

The system seems to work best with more like 50 ounces. If you're using gauges look for about 33 psi on the low side. Thats on an 80 degree day - with the cab cooled down, buttoned up and the vent on recirc.

But if everything is right, and you don't overcharge, this system can get damn CHILLY. It's easy to get a dash vent discharge temp of 42 F, even on a 90 degree day.

Be sure:

All moisture and non-condensables removed (pull down to 29.5" and hold overnight)

Orifice screens (inlet and outlet) are clear

Heat exchangers clean - (condenser and evap flushed internally and fins blown out)

Blend door function. Able to fully stroke hot to cold - and seal flexible/intact
 
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HotRodPC

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On these Freon amounts, if you use R134A, aren't you supposed to use about 20% less if the specs are for R12? I've heard to use less R134A due to higher pressure. And is this 33psi you speak of Chengy, is that the same for R12 and R134A ?
 

HotRodPC

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Hey Pops, so does the HT6 look and mount similar to an HR6? I've got the HR6 or the DR6 on my 454, and the 350 has the Pancakce R4 I do beleive.
 

oneluckypops

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Hey Pops, so does the HT6 look and mount similar to an HR6? I've got the HR6 or the DR6 on my 454, and the 350 has the Pancakce R4 I do beleive.

No the Vortecs use the serpentine setup which the compressor (HT6) sits on top of the powersteering pump bracket and bolts straight down with 4 bolts.


134a in these should actually be around 25-30% less then R12. But with that said I ran into a snag when I charged mine and havent felt like ******* with it anymore lol. I think I only have about 2-2.5 cans in mine right now. High pressure cut out switch is compressor mounted, which is held in with a snapring. I thought it was in the groove but evidently it wasnt cause after I got 1 can in it it blowed the switch out of the compressor and I lost all the freon that i just put in it lol. I didnt have enough freon to fill it totally so it is being ran low right now. YA YA YA I know, but hey times hard to come bye right now. Sucks to with 120 degree heat indexs.
 

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