AC Confusion-Need Help

[projectmidnight74]

Afternoon/Evening everyone,

I havea 74 c10. Rebuilt the Small Block 350 and changed it to a vbelt kit for style points. Also changed the ac compressor to the B series or, shallow/round unit and relocated it from the driver to the passenger side. Here is where the problems began. I didn't buy a kit that had all the hoses needed to get everything back to where it needed to be originally. We are having issues figuring out how to attack this new problem. I already have new condenser on the way that is the same as the original that was in it 35 years ago, this new compressor has us with a short line running to the driver side to connect to the condenser. What hose do I need to get, or do I simply make a steel extension to go from the condenser to the needed area of connection. Would that cause a pressure issue. And if I need to attach a diagram I am working on one now. Please help.

 

[Bextreme04]

Afternoon/Evening everyone,

I havea 74 c10. Rebuilt the Small Block 350 and changed it to a vbelt kit for style points. Also changed the ac compressor to the B series or, shallow/round unit and relocated it from the driver to the passenger side. Here is where the problems began. I didn't buy a kit that had all the hoses needed to get everything back to where it needed to be originally. We are having issues figuring out how to attack this new problem. I already have new condenser on the way that is the same as the original that was in it 35 years ago, this new compressor has us with a short line running to the driver side to connect to the condenser. What hose do I need to get, or do I simply make a steel extension to go from the condenser to the needed area of connection. Would that cause a pressure issue. And if I need to attach a diagram I am working on one now. Please help.

Did it originally have one of the long A-4 compressors? Why did you switch to a passenger side mounting?

You will likely need to get a hose kit from one of the companies like Vintage air and then have a local hydraulic hose company crimp the end fittings on them once you have cut the hoses to the right length.

 

[projectmidnight74]

Hope this helps.

 

[projectmidnight74]

Did it originally have one of the long A-4 compressors? Why did you switch to a passenger side mounting?

You will likely need to get a hose kit from one of the companies like Vintage air and then have a local hydraulic hose company crimp the end fittings on them once you have cut the hoses to the right length.

I believe it did, but me being excited and not checking ANYTHING, I thought this was going to be an easier process going with a new one. Here I am now, a year in on a 6 month project and beginning to hate it lol.

 

[Bextreme04]

I believe it did, but me being excited and not checking ANYTHING, I thought this was going to be an easier process going with a new one. Here I am now, a year in on a 6 month project and beginning to hate it lol.

Yep, you should have kept that. You can buy brand new manifold/lines for the A4 and everything would have bolted up just like stock. You can get rebuild kits for the compressor for about $25 and it's pretty easy to do. If you still have it, I'd go back to the stock setup and stop worrying about this custom mess.

 

[projectmidnight74]

Yep, you should have kept that. You can buy brand new manifold/lines for the A4 and everything would have bolted up just like stock. You can get rebuild kits for the compressor for about $25 and it's pretty easy to do. If you still have it, I'd go back to the stock setup and stop worrying about this custom mess.

Yeah, unfortunately, its gone. So could I use a steel line adapter to get me that extra foot needed or do I need to do a kit and do it that way.

 

[sidschev]

sounds like its a custom job all the way man..your gunna have to cut hoses and have the ends crimped on.......

 

[75gmck25]

The big compressor in the picture is the long, heavy A6, and the smaller pancake compressor is the R4. Both are generally not too reliable.

I’ve never seen the compressor mounted on a squarebody on the passenger side. Where is the alternator mounted?

Extending the compressor lines should not cause problems. However, getting the right ends on all the fittings can be a challenge because most use o-rings, but there may be some variations. There is an A/C supply house in Phoenix (Ackits.com) and one in Fort Worth (oldairproducts.com) that probably have everything you need.

On a ‘74 you also probably have a TXV (thermal expansion valve) instead of a simple orifice valve with cycling compressor. I’ve never seen a TXV in the wild, since in ‘75 (my truck) they switched to using an orifice valve.

 

[projectmidnight74]

Update and I will attach pics. Everything is running and doing great. But I still have the ac hotwired. The HPCO switch did not work for the connection that we have. On the accumulator, the switch will not thread on as it is a little too tight. Is there a another switch I can use to get this thing to cycle. I am ok with doing it manually but, I would love for it to work as advertised. What switch should I be looking for here gents. Pics attached.

 

[projectmidnight74]

Pics

 

[sublimeobs]

See if this link to RockAuto works. The link is for an '84, but should be fine. Note that there are two types - Low Pressure Cut Off (LPCO) and High Pressure Cut Off (HPCO). The one you're looking for on the Accumulator is the LPCO switch.

You're past this, but if anyone else is looking - coldhose.com is a good source for AC hose and fittings.