Help upgrading the AC on a 1985 C20 6.2L

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5akman

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My son just purchased a low mile 6.2l out of an airport tug to replace his original 6.2 of unknown condition. He has factory air on the original engine. We damaged the AC condenser when we pulled the engine out so that got me thinking about upgrading the AC system since we have to now replace the condenser. I've read about using larger pumps and a parallel flow condenser? Any suggestions as we live where is it routinely over 100 degrees in the summer and he does lots of in town, stop and go driving so AC is mandatory!

thanks!
 

asltrfl

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Let me get this right, this is your "Son's truck"? It's over 100F. in the Summer? Just a guess, but it's a 1984 with a small-block. Stop-and-go driving? Well R-12 is out of the question, unless you live in Mexico. 134-A? Good stuff indeed! But maybe do like the rest of us when we were young...roll the damn windows down, give that small-block some respect, and learn that life, like one's first wife, ain't easy (or maybe she was, like mine).

Sorry, but I and my siblings grew up in Lake Havasu, AZ. Where it was 115+F. all Summer long, every Summer. My daddy told us if we wanted A/C in our cars we better get better educated, find a better job, or marry a rich spouse, and buy a brand new car every few years.

He taught us that A/C is the weakest link, the most prone to fail, and the compressor is one of the most expensive to fix components in an automobile, short of trans, heads, or engine. So guess what, I went to Auto Mechanic School in Phoenix...because I wanted Air Conditioning in my Cars/trucks. Daddy was a Mechanic, son is a mechanic.

Fast forward to today. I moved away from AZ, went north to the Mountains of Utah. And now when my "Tea-cup kids" whine about how hot it is when it's 84F. and their A/C doesn't work, I tell them "roll the damn windows down, respect that small-block Chevy, and thank God you don't have to saddle a horse every time your Facebook friends want to meet at Starbucks". Really?
 

5akman

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Nope, 1985 C20 6.2l diesel from factory and 6.2l to this day. Since the pull out engine is going in and we banged up the compressor pulling the old engine out, it makes sense to upgrade the existing AC components at this time.

Feel free to ramble on, I don't give a sh*t about your tea cup kids, if my son wants to upgrade and has the money to do so, that's his prerogative. I was looking for info on compressors, condensers etc, not your life lessons.
 

1987 GMC Jimmy

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What’s the compressor situation now? A6? R4? I don’t know what’s typical for diesels. People on here rave about doing the conversion to Sanden style compressors, which axial compressors are known to be better than radials anyway. I would think the conversion would be real easy from an A6 to a Sanden, and if you have the right bracket, almost as easy for R4 to Sanden. Also, IIRC, the blue Ford o-tube is better for city-heavy, stop and go driving. Some variants are better for highway conditions, which I think the white o-tube that’s likely in there excels in personally. Another personal thought is that I’d avoid parallel flow condensers and stick with the older design because of the problems that people have reported when flushing them, especially if there’s trash or compressor metal lodged in them. Hopefully others will chime in with other ideas. I think @yevgenievich knows a lot more about the Sanden stuff.
 

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Nope, 1985 C20 6.2l diesel from factory and 6.2l to this day. Since the pull out engine is going in and we banged up the compressor pulling the old engine out, it makes sense to upgrade the existing AC components at this time.

Feel free to ramble on, I don't give a sh*t about your tea cup kids, if my son wants to upgrade and has the money to do so, that's his prerogative. I was looking for info on compressors, condensers etc, not your life lessons.
It appears a lot of this could have been avoided by simply reading your original post or even the title! I can’t help with your upgrade but I wish you luck with it.
 

5akman

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What’s the compressor situation now? A6? R4? I don’t know what’s typical for diesels. People on here rave about doing the conversion to Sanden style compressors, which axial compressors are known to be better than radials anyway. I would think the conversion would be real easy from an A6 to a Sanden, and if you have the right bracket, almost as easy for R4 to Sanden. Also, IIRC, the blue Ford o-tube is better for city-heavy, stop and go driving. Some variants are better for highway conditions, which I think the white o-tube that’s likely in there excels in personally. Another personal thought is that I’d avoid parallel flow condensers and stick with the older design because of the problems that people have reported when flushing them, especially if there’s trash or compressor metal lodged in them. Hopefully others will chime in with other ideas. I think @yevgenievich knows a lot more about the Sanden stuff.

Compressor is a Harrison General Motors 443 /J639 R12 unit. Never heard of that brand
 
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Blue Ox

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Honestly the factory systems in these trucks kicked @$$. Providing you can still find R12. If you restored the factory system you could hang meat in the cab.
 

5akman

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Honestly the factory systems in these trucks kicked @$$. Providing you can still find R12. If you restored the factory system you could hang meat in the cab.

I hadn't heard that and my son just recently bought the truck and the AC didn't have any freon in it so we couldn't test the temp. I'll check with the local AC shop and see if they have some R12 kicking around...
 

asltrfl

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So sorry, my post came out totally wrong. No wonder my kids hate me, avoid me like the plague, and believe that socialism is somehow connected to facebook. Again, Forgive me. Sorry
 

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DBarre

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Sounds like it would be the A6. It might be good to look into the Sanden upgrade. Check the A/C section of the forum for the thread.
 

82Diesel

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Honestly the factory systems in these trucks kicked @$$. Providing you can still find R12. If you restored the factory system you could hang meat in the cab.

You can buy R-12 on eBay still.
 

yevgenievich

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Sanden retrofits work well, new hoses, parallel flow condenser and blue orifice tube can be a good combo. But for a single cab truck, original condenser usually enough.
 

5akman

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Sanden retrofits work well, new hoses, parallel flow condenser and blue orifice tube can be a good combo. But for a single cab truck, original condenser usually enough.

So could he do the Sanden upgrade minus the condensor?
 

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