skysurfer
Full Access Member
- Joined
- Oct 23, 2010
- Posts
- 2,646
- Reaction score
- 2,011
- Location
- west coast
- First Name
- John
- Truck Year
- 1989 Suburban
- Truck Model
- V2500
- Engine Size
- 5.7/TH400/NP241C
I've finished my Sanden compressor install. It was supposed to be exactly what Viktor did with his in this thread (https://www.gmsquarebody.com/threads/r4-to-sanden-whith-stock-ac-lines-for-serpantine.22437/) but I ended up doing a couple of things differently, some by choice and some not. I ordered all of the parts he listed since his '91 and my '89 are essentially the same. This is definitely not a "how to" thread, just my experience with working on ac for the first time.
After removing the R4 compressor, condenser, and related items, I needed to flush out the evaporator and rear ac unit. I have an air compressor with several air drying devices attached so I wasn't concerned about blowing moisture into the ac system. I fabbed up a tool to hold the Supercool A/C Flash Flush but I had to filter the fluid in order to have enough so that I could flush the lines several times in both directions.
I attached a hose to the exit side of the part I was flushing to catch the fluid in a gallon container, then poured the fluid through a household 3 micron rated water filter. With one end of the filter plugged I poured the solvent in the other end and caught the clean solvent in a second container.
The system wasn't contaminated at all. I expected all kinds of carnage considering the R4 compressor sounded like someone dropped a spoon into a garbage disposal, but the orifice tube looked pretty good compared to pics I've seen online. The new tube installed is the reduced size Ferd blue for better cooling.
I really wanted to install a parallel flow condenser after reading about how much more efficient they are compared to the oem unit. After much searching I located a good match size-wise, but the concession was they don't have the pre-formed connection tubes for a drop-in installation. Here's the old and new for comparison.
I had to make mounting brackets, and needed to offset the condenser to one side in order to have room for the plumbing. A scrap piece of 3" aluminum C channel was found at the local steel yard and was the perfect size and thickness after some cutting.
Note in the pic above there's a scrap bit of material temporarily attached to the bottom of the condenser. That gave me the height I wanted and kept the condenser level while I figured out where to drill the holes in the core support for the side brackets.
This next pic shows why I had to offset the condenser. The bottom connection didn't have much room for plumbing but a 90 degree fitting was used to feed the line out the top.
Using one of the Sanden mounting bracket kits available online, I bolted up the compressor and then went to install the factory style hoses I got from Rock Auto. Problem. One of the aluminum lines was hitting the valve cover. I tried rotating the compressor 90 degrees but that made the other line unable to go where it was supposed to. I got around this by removing just the bottom bolts and rotating the compressor up until I had clearance on the valve cover.
I measured the distance between the mounting holes and made short extension brackets to hold the compressor up. Of course even that simple solution wasn't so simple. The bracket kit uses spacers of two specific thicknesses at that location to keep the compressor aligned with the rest of the serpentine components. I had scrap metal the correct thickness for the front one but had to weld two different pieces together in order to get the correct thickness on the back one.
That was a minor side issue caused by the new mounts. The belt I had ordered per Viktor's thread ended up being a little too short. A new belt a couple inches longer made up the difference.
With the compressor and condenser in, the rest was pretty easy. Of course with a Suburban there's work to be done at the back. I had removed the rear expansion valve prior to flushing and connected the lines with a temporary bit of hose.
And while I was there I replaced the o-rings in the lines with the proper r134 ones. Here:
And underneath. I bet it's easy to forget about these ones.
One other problem I had was the compressor cycling switch. Rock Auto shows a certain part number for my year, make, and model, but when you get the part it has the wrong electrical connection. It should have two exposed spade connectors but the one they sent has recessed connectors for a GMT400 series. Typical problem since the trucks changed in '88 but Blazers, Burbs, and Tons carried through to '91. I sent that one back and got one for an '87 burb locally with the right connectors. Wrong part on the left.
Of course, we've all gotten into the situation where you need to hold a nut while you start the bolt but can't quite reach it with more than one finger. I could barely reach it with my middle finger so...
Last task was getting custom lines to connect the condenser. I couldn't just go to a guy and say I need two lines xx length because the fittings have to be clocked a certain way before crimping so they point in the right direction after installation. I ordered the parts online and put the lines together how they needed to be. A Sharpie marked the orientation of each fitting to hose and then a local shop crimped them for me. I told the guy what I was working on and he did the crimping for free. A Chevy guy apparently. With the custom length lines I didn't need the ATC6302 fitting that Viktor used on his installation.
Close tolerance between the upper hose and the core support.
Last order of business was charging. I didn't want to do that part since I don't have a vacuum pump so I took it to my local mechanic. It would have been a good idea to pressurize the system with nitrogen to check for leaks but I would have had to drive into the next county for that service. He pulled vacuum for an hour and it held fine so he went ahead and charged the system. I had added 100cc of oil to the 200 that Sanden put in. I calculated it would take 3.125 lbs. of refrigerant and the actual was 3.23 lbs.
We're still having a bit of a heat wave out on this end of the country and I had this done on a 89 degree day. Temp reading was pretty good considering the truck was sitting idle for 15 minutes when this reading was taken.
I think everything turned out ok. The acid test will be seeing if it still blows cold next summer.
After removing the R4 compressor, condenser, and related items, I needed to flush out the evaporator and rear ac unit. I have an air compressor with several air drying devices attached so I wasn't concerned about blowing moisture into the ac system. I fabbed up a tool to hold the Supercool A/C Flash Flush but I had to filter the fluid in order to have enough so that I could flush the lines several times in both directions.
You must be registered for see images attach
I attached a hose to the exit side of the part I was flushing to catch the fluid in a gallon container, then poured the fluid through a household 3 micron rated water filter. With one end of the filter plugged I poured the solvent in the other end and caught the clean solvent in a second container.
You must be registered for see images attach
The system wasn't contaminated at all. I expected all kinds of carnage considering the R4 compressor sounded like someone dropped a spoon into a garbage disposal, but the orifice tube looked pretty good compared to pics I've seen online. The new tube installed is the reduced size Ferd blue for better cooling.
You must be registered for see images attach
I really wanted to install a parallel flow condenser after reading about how much more efficient they are compared to the oem unit. After much searching I located a good match size-wise, but the concession was they don't have the pre-formed connection tubes for a drop-in installation. Here's the old and new for comparison.
You must be registered for see images attach
I had to make mounting brackets, and needed to offset the condenser to one side in order to have room for the plumbing. A scrap piece of 3" aluminum C channel was found at the local steel yard and was the perfect size and thickness after some cutting.
You must be registered for see images attach
You must be registered for see images attach
Note in the pic above there's a scrap bit of material temporarily attached to the bottom of the condenser. That gave me the height I wanted and kept the condenser level while I figured out where to drill the holes in the core support for the side brackets.
This next pic shows why I had to offset the condenser. The bottom connection didn't have much room for plumbing but a 90 degree fitting was used to feed the line out the top.
You must be registered for see images attach
Using one of the Sanden mounting bracket kits available online, I bolted up the compressor and then went to install the factory style hoses I got from Rock Auto. Problem. One of the aluminum lines was hitting the valve cover. I tried rotating the compressor 90 degrees but that made the other line unable to go where it was supposed to. I got around this by removing just the bottom bolts and rotating the compressor up until I had clearance on the valve cover.
You must be registered for see images attach
I measured the distance between the mounting holes and made short extension brackets to hold the compressor up. Of course even that simple solution wasn't so simple. The bracket kit uses spacers of two specific thicknesses at that location to keep the compressor aligned with the rest of the serpentine components. I had scrap metal the correct thickness for the front one but had to weld two different pieces together in order to get the correct thickness on the back one.
You must be registered for see images attach
You must be registered for see images attach
That was a minor side issue caused by the new mounts. The belt I had ordered per Viktor's thread ended up being a little too short. A new belt a couple inches longer made up the difference.
With the compressor and condenser in, the rest was pretty easy. Of course with a Suburban there's work to be done at the back. I had removed the rear expansion valve prior to flushing and connected the lines with a temporary bit of hose.
You must be registered for see images attach
And while I was there I replaced the o-rings in the lines with the proper r134 ones. Here:
You must be registered for see images attach
And underneath. I bet it's easy to forget about these ones.
You must be registered for see images attach
One other problem I had was the compressor cycling switch. Rock Auto shows a certain part number for my year, make, and model, but when you get the part it has the wrong electrical connection. It should have two exposed spade connectors but the one they sent has recessed connectors for a GMT400 series. Typical problem since the trucks changed in '88 but Blazers, Burbs, and Tons carried through to '91. I sent that one back and got one for an '87 burb locally with the right connectors. Wrong part on the left.
You must be registered for see images attach
Of course, we've all gotten into the situation where you need to hold a nut while you start the bolt but can't quite reach it with more than one finger. I could barely reach it with my middle finger so...
You must be registered for see images attach
Last task was getting custom lines to connect the condenser. I couldn't just go to a guy and say I need two lines xx length because the fittings have to be clocked a certain way before crimping so they point in the right direction after installation. I ordered the parts online and put the lines together how they needed to be. A Sharpie marked the orientation of each fitting to hose and then a local shop crimped them for me. I told the guy what I was working on and he did the crimping for free. A Chevy guy apparently. With the custom length lines I didn't need the ATC6302 fitting that Viktor used on his installation.
Close tolerance between the upper hose and the core support.
You must be registered for see images attach
You must be registered for see images attach
Last order of business was charging. I didn't want to do that part since I don't have a vacuum pump so I took it to my local mechanic. It would have been a good idea to pressurize the system with nitrogen to check for leaks but I would have had to drive into the next county for that service. He pulled vacuum for an hour and it held fine so he went ahead and charged the system. I had added 100cc of oil to the 200 that Sanden put in. I calculated it would take 3.125 lbs. of refrigerant and the actual was 3.23 lbs.
We're still having a bit of a heat wave out on this end of the country and I had this done on a 89 degree day. Temp reading was pretty good considering the truck was sitting idle for 15 minutes when this reading was taken.
You must be registered for see images attach
I think everything turned out ok. The acid test will be seeing if it still blows cold next summer.
