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Long A/C Compressor vs. short A/C compressor

Landon730

Active Member
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Location
Greenwood Arkansas
Thread starter #1
I have a 84 6.2 square body with A/C but I can't decide to keep this compressor or get a short smaller one like on the early 6.5. Is there any advantages to the longer one?
 

THEFERMANATOR

FRANKENBURBAN
Staff member
Lead Moderator
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Staff #2
If it was mine, I would do the sanden 507 swap. The harrison pancake compressors are nice for compact installations, but reliability with r-134 hasn't been the best with them. And the early styles are said to be very good, but take up alot of real estate. The Sanden 507 is very reliable, used all over, and is in between the 2 in size. That would be my suggestion if your looking to change.
 

WarWagon

Well it hits on 7 of 8...
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AZ
#3
I wouldn't willingly put a early 6.5 POS R4 "pancake" compressor on anything. Keep what you got or use the suggested even better Sanden 507 because it's light years better than the R4 leakmaster grenade. The R4 was a POS even with the low head pressures and better oil flow of R12. The only way I get a R4 to live beyond the miserable 2 year warranty is to evac and charge the system every year and run alternate refrigerant.
 

Landon730

Active Member
Messages
192
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Location
Greenwood Arkansas
Thread starter #4
I wouldn't willingly put a early 6.5 POS R4 "pancake" compressor on anything. Keep what you got or use the suggested even better Sanden 507 because it's light years better than the R4 leakmaster grenade. The R4 was a POS even with the low head pressures and better oil flow of R12. The only way I get a R4 to live beyond the miserable 2 year warranty is to evac and charge the system every year and run alternate refrigerant.
Ok so my main question is which one gets colder lol? I don't care about real estate, thats not why I wanna change it, just want the one that works better.
 

WarWagon

Well it hits on 7 of 8...
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#5
Sanden 507 or yours and IMO the Sanden is the more modern and efficient unit. The R4 is inefficient turning HP into heat the heat has to be removed from the condenser or the AC doesn't cool well - HP draw be dammed. You want to focus on cooling the condenser to get the AC cold. The engine fan is just that and overheats the condenser till the engine warms up and gets the fan on. Suggesting the 454 aux cooling fan here that comes on with the compressor. Not sure if it fits the OBS of yours - so rig an electric fan to help the AC.

If you want to ice up the evaporator, and I do even in 115+ weather on any less then high fan speed, run alternate hydrocarbon refrigerant. Without adequate condenser airflow even it will struggle. I need a evaporator temp switch to stop the freeze ups because GM regulates temp by pressure. R12/R134a Pressure has this stuff well below freezing before it kicks off. https://www.es-refrigerants.com/pro...6-ounce-can-equivalent-16-oz-134a/details.asp
 

Will L.

Well-Known Member
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Location
Boulder City Nv
#6
I’ll jump on board for the 507. And yes at idle electric fans can help, but I would rather see $ spent on TLTD coating the cooling stack. Here is why:
Think how good ol r12 was then drop in the 134a and it could barely do anything. The “fix” was enlarged condensor by 33%. Exactly the ratio of r12-r134a exchange differences. Then people saw how much the bigger condensor did and added them to factory r134a systems and POW! ice in the face a/c.
Now what ratio does TLTD affect the radiators, cac, etc? 33-35% depends on base material.

No brainer imo. Put in the sanden for the long haul, and just as important coat the dang condensor instead of paint that holds in heat.
 

WarWagon

Well it hits on 7 of 8...
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#8
We really don't have the room on a 1993 to drop in a longer compressor. Swap the accessories brackets to a 96+ with the AC on driver side and maybe.
 

deejaaa

Diesel Beginner
Messages
1,657
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Location
Texas
#9
We really don't have the room on a 1993 to drop in a longer compressor. Swap the accessories brackets to a 96+ with the AC on driver side and maybe.
do ya mean swap brackets from a 96+? i have the complete 96 engine in the shop now with all brackets. would anything else need changing?
 

WarWagon

Well it hits on 7 of 8...
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#10
Yes. Need longer AC hoses - have them made. You have the altonator? Check the clearence on the t stat to AC. The tensioner is critical as the 1993 spring has to take the compressor load where the 1996+ doesn't and is a weaker spring.
 

THEFERMANATOR

FRANKENBURBAN
Staff member
Lead Moderator
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Staff #14
You can run the sanden on the 93, but you have to move it furthur out to clear things. To swap to the 96+, you have to change all the accesories, tstat housing, hoses, try to clear the throttle bracket, and all that. Then you have the infamous belly leaker compressor. The harrison radial compressors aren't horrible, but they just are not holding up anymore.
 

deejaaa

Diesel Beginner
Messages
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465
Location
Texas
#15
Yes. Need longer AC hoses - have them made. You have the altonator? Check the clearence on the t stat to AC. The tensioner is critical as the 1993 spring has to take the compressor load where the 1996+ doesn't and is a weaker spring.
i have everything that was bolted to the engine, except PS pump.
i'll do some reading.
 

Landon730

Active Member
Messages
192
Likes
115
Location
Greenwood Arkansas
Thread starter #16
You can run the sanden on the 93, but you have to move it furthur out to clear things. To swap to the 96+, you have to change all the accesories, tstat housing, hoses, try to clear the throttle bracket, and all that. Then you have the infamous belly leaker compressor. The harrison radial compressors aren't horrible, but they just are not holding up anymore.
Quick question - I can't get the blower to kick on and it looks like it was replaced not long ago. (Truck was last on road in 2008 lol) But anyways I THINK its the control head because the sliders feel pretty loose. Checked with a multimeter and we have voltage to the relay under the hood. Had to run a direct wire from a/c compressor to battery to charge the system. Blows cold air out the floor vent but whenever I use the sliders on the control head nothing changes.
 
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