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R4 to Sanden Compressor Swap, anyone have part numbers?

aandpman

aandpman

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I'm finally tired of sweltering. Adding freon every spring is not working anymore. The last time I added, using gauges, the low side was up to 70psi and the high side was lower than it needed to be. The diagnostic info I read said that was a pretty good sign that there's at least one bad reed valve in the compressor.

So, I'm starting to research what parts to get to convert over to a sanden compressor. So, hey, what better place to start than with my buds here on CK? I have looked at some of the posts and haven't really found info for my specific application.

I'm hoping someone here has done this exact swap and has info on what brackets, compressor, and condenser to get, and who to get them from.

Here it is:
88K5
350 TBI (stock)
Drivers' side r4 compressor (currently), already converted to R134a by p.o.
Single Vbelt driving it.

For reference, here's a visual:

picture.php
 
FWIW most of the swaps I've seen have been on the passenger side, mine is on the driver's side.
 
Just throwing this out there...

The easiest and most cost-effective swap will be another R-4. Most reviews are positive on the newer AC Delco ones, but bad on brand x reman. People praise the "better MPG" with a Sanden, but that's due in part to it just having less displacement. So to get good cooling with a smaller compressor, you need more efficiency elsewhere. For this, most look for parallel flow condenser, which is good in theory, but in practice the ones you find that fit are (once again) smaller than the original one (less surface area, plus some air goes around it). So instead of the theoretical 15% improvement or whatever, you get like 5% (or a reduction if you don't solve the air flow issue). Our stock condensers are huge.

An AC Delco R-4 is $350? (haven't checked lately). Compare that to a new parallel flow condensor (+brackets), Sanden, new lines, mounting brackets, spacers and hardware and possibly adapter fittings. You're paying a lot more for a system that doesn't work any better and is harder to find replacement parts for. Now if you happen to find a used R-4 that is quiet, you're even further ahead.
 
If your compressor is otherwise working (and not super loud) and just a bad valve or two, why not replace them? I did a thread a while back on tearing one down. In fact, I probably still have the valves in these pictures sitting around. That compressor cooled when it was pulled, too - just noisy.

http://coloradok5.com/forums/showthread.php?t=307840
 
Thanks for the replies..

Mine has been pretty noisy for a long time, so I'd like to address that issue, whatever fix I choose to do.

If the newer R4's are in fact made better, I'd not be opposed to going with one.

As for doing a repair on the existing unit, I don't have any fears of tearing into one...I'm a fairly competent driveway mechanic...heck, I aced airframe and powerplant school and have my FAA A&P license. I'm definitely going to check out your thread on tearing into one. I just hope I can quiet it down. the way I look at it - I'm not losing anything if i tear into it - it's not working that great now, and the worst case is I'd have to replace it, and I was going to do that anyway. If I manage to pull off a fix, I'd be that much ahead finacially anyway.

Gonna take a look at your thread...
 
I'm in the same boat as aandpman.

I have an '88 also, with the 2 "V" belt / 1 "serpentine" type belt and have been looking for '98-'99 5.7 setups in our local pick-a-parts to rob the entire serpentine system (which includes the Sanden compressor).

The nice thing about those year trucks is that the compressor is on the drivers side and alternator on the passenger, so no huge change in wiring. As far as I have researched, the brackets and accessories should bolt right up to our blocks.
 
Blue85 said:
Just throwing this out there...

The easiest and most cost-effective swap will be another R-4. Most reviews are positive on the newer AC Delco ones, but bad on brand x reman. People praise the "better MPG" with a Sanden, but that's due in part to it just having less displacement. So to get good cooling with a smaller compressor, you need more efficiency elsewhere. For this, most look for parallel flow condenser, which is good in theory, but in practice the ones you find that fit are (once again) smaller than the original one (less surface area, plus some air goes around it). So instead of the theoretical 15% improvement or whatever, you get like 5% (or a reduction if you don't solve the air flow issue). Our stock condensers are huge.

An AC Delco R-4 is $350? (haven't checked lately). Compare that to a new parallel flow condensor (+brackets), Sanden, new lines, mounting brackets, spacers and hardware and possibly adapter fittings. You're paying a lot more for a system that doesn't work any better and is harder to find replacement parts for. Now if you happen to find a used R-4 that is quiet, you're even further ahead.
Click to expand...

I agree, with the later AC Delco R4 Compressors. I usually have nothing good to say about R4’s after spending decades of R&Ring failed ones from various GM vehicles but the last several new AC Delco R4’s have been quiet and actually seem to be staying together. You can’t say that for a dime store R4 or even one from Napa these days. Makes me wonder if GM retooled some of the bits and pieces in them as of late. I’m sure the rebuildable pool of old R4 compressors are getting pretty sketchy by now but that sure doesn't stop the dime store parts stores like Autozone from pimping them out (A1 Cardone). Even at that, I’m still more of a fan of the Delphi HT6 compressor but I would probably give a new AC Delco R4 a try if I had a rig that still ran a R4.


B Red Dodge said:
I'm in the same boat as aandpman.

I have an '88 also, with the 2 "V" belt / 1 "serpentine" type belt and have been looking for '98-'99 5.7 setups in our local pick-a-parts to rob the entire serpentine system (which includes the Sanden compressor).

The nice thing about those year trucks is that the compressor is on the drivers side and alternator on the passenger, so no huge change in wiring. As far as I have researched, the brackets and accessories should bolt right up to our blocks.
Click to expand...

Actually, you are talking about the last serpentine belt accessory drive for the old SBC. Those ran from 1996 to 2004 on 4.3, 5.0 and 5.7L engines. Hell, the 4.3L continued to use those same brackets up until 2013. The compressor on those brackets is also Delphi HT6, not a Sanden. As mentioned above, the HT6 is my all-time favorite compressor (well above the overhyped Sanden) where I run them on everything (’78 K10 w/8.1L, ’89 Suburban w/8.1L, ’93 Sportside w/7.4L, and stock Silverado with 8.1L). The 96 and later SBC (and 4.3L) will bolt on to an older SBC but depending on the engine year but there may be a hole or two to be drilled in the cylinder head. No biggie, I did that almost 20 years ago when swapping on serpentine on my old 350 albeit it was a bit nerve racking taking a drill bit to a perfect good cylinder head. Don’t forget the reverse rotation water pump when doing serpentine swaps.

For a SBC, these are the best serpentine brackets and A/C compressor around in my opinion. 1996 and later 5.0, 5.7 and 4.3L's. The alternator that fits these brackets is a good unit too (CS-144) with 124 AMP and 140 AMPS options.
1188134689_577e25664d.jpg
 
I have 90% of the parts needed in my garage to do the same with my 88 burb. Biggest thing you'll need other than the full front set-up for a 96-00 Vortec motor is a water pump from an 88-95 K1500 pick up. It's serpentine but with the water passages like we need for the TBI motor. You could also use the Vortec reverse fan, but I'm changing to electric fans at the same time. I still need to get an adaptor for the alternator, but hopefully sometime later this summer I can get mine done.
 
There is a web site Allen Groves that has a bracket setup for the drivers side and a new Sanden compressor for 180.00. I just replaced my whole system for the second time after many flushes and multiple compressor changes. Found this site after........ Go figure.

One more attempt with an R4.
 
Got my 1989 Suburban's A/C finalized this afternoon after screwing around Napa for weeks to find the right compressor block and all the fittings in order to make the custom hoses for the 8.1L running a HT6 A/C compressor. You don’t even hear this Delphi HT6 run, just a slight click when the clutch first engages just like a new truck. Blowing 54 degrees out the vent today at 98 degrees ambient :waytogo:
18684269204_b1bf808ec8_c.jpg
 
Larry said:
Got my 1989 Suburban's A/C finalized this afternoon after screwing around Napa for weeks to find the right compressor block and all the fittings in order to make the custom hoses for the 8.1L running a HT6 A/C compressor. You don’t even hear this Delphi HT6 run, just a slight click when the clutch first engages just like a new truck. Blowing 54 degrees out the vent today at 98 degrees ambient :waytogo:
18684269204_b1bf808ec8_c.jpg
Click to expand...

oh yeah...something new on my to-do list...:waytogo:
 
I did this same swap to 134a with a Sanden style compressor in my 84 K5 about 6 years ago.

At the time, the Sanden compressor's were really expensive, and I was on a Pizza delivery guy budget, so I went with a Chinese knockoff Sanden from Nostalgic AC.

I don't remember how much it ran me, and I can't find the invoice anymore, but I remember it was significantly cheaper than a real Sanden at the time.

Looks like the relevant # on my Compressor was a CO4628C, which crosses out to a Sanden 709 style compressor.

I then used:
AC Delco 156960 Condenser
FOUR SEASONS 33190 A/C Accumulator
FOUR SEASONS 26739 A/C System O-Ring & Gasket Kit
FOUR SEASONS 38623 A/C Orifice Tube

All from Rock Auto. I had custom hoses made at my local EVCO House of Hose, which ran me about $50 if I recall.


I custom macgyvered a rig to support the compressor using a combination of the original R4 mounting hardware, and some bar stock I had laying around.




This was in the early days of my learning how to fabricate, and at the time, I had little more in the way of tools then you typical hand stuff and a small vice, so forgive the quality of the work.


I drove the truck to a local shop and had them evacuate the system and charge it with 134a, and I haven't touched it since.

the AC still blows super cold, and it drops to within 80% of max cooling within 5 minutes usually. The compressor is absolutely silent, at least as far as I can tell (the truck does have a glasspack on it after all :D ) All I can hear is a small click when the clutch engages. If it wasn't for the slight RPM drop, and the (small but noticeable) loss of power on my POS 305, I wouldn't even be able to tell it was engaged.

Thanks to my terrible rig job (i hate even looking at it, it galls me to even post it here) the belt has had an occasional squeal on start and higher rpm since day one, but its occasional, and I don't drive with the AC on enough for it to really bother me. When I am by myself, I usually leave it off to save gas and power, since my weak-sauce 305 needs every last horse just to move this beast. I really only fixed the AC for the benefit of passengers...

If someone makes a bracket to just slap this style of compressor in, I would do it in a heartbeat. Not worth rigging it up like I did.



My memory is telling me that there was something I had to do with the pressure switch, but damned if I can remember the details now. I don't show it in my electronic receipts as having been replaced, but something is nagging me that I did something with it. :dunno:


Good luck with your conversion :waytogo:
 
The pressure switch on the accumulator?

I'm thinking you swapped it for a 134a switch. There's also an adjustment screw in it to fine tune the compressor start/stop pressure.
 
I just got done doing an R4 to Sanden on my '91. Its a passenger side mount style, so my parts list below maybe different.

* Sanden SD5H14 (ebay, genuine, new in box, $150)
* R4-to-Sanden conversion Bracket from Nostalgic AC ($88)
* Gates belt K060988 ($15)
* Parallel-Flow R134a Condenser from RockAuto ($160 - i think ...)
* New custom A/C hoses - $100
* Discharge/Recharge R134a & labor from AC shop - $100. They also updated the pressure switch so my electric fans would come on. That was included in the labor.

I am extremely glad I did this. Temps coming out of the vents are around 56-59F. Also I don't feel the engine being dragged down.

Good luck!

IMG_0584.JPG

IMG_0591.JPG

IMG_0593.JPG
 
i'm running a Sanden 508 on a Holley bracket for my 5.3L. They make kits for older engines also. Like Larry's HT-6, you don't hear a thing, just the clutch click when you turn it on, it also uses a lot less power than an R4 compressor.
8271d44784693a01e705079a61a87125.jpg
 
muddysub said:
i'm running a Sanden 508 on a Holley bracket for my 5.3L. They make kits for older engines also. Like Larry's HT-6, you don't hear a thing, just the clutch click when you turn it on, it also uses a lot less power than an R4 compressor.
8271d44784693a01e705079a61a87125.jpg
Click to expand...

That looks great! Definitley the cats meow for a Gen III engine! :waytogo:
 
aandpman said:
FWIW most of the swaps I've seen have been on the passenger side, mine is on the driver's side.
Click to expand...

How's the project coming? And I'm also subscribed
 
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