AC repair/overview on a 30 year old truck

[SAATR]

Compressor - Sanden conversion is preferable, but NEW is the only way to go. No reman.
Condenser - Parallel flow as suggested by 1998_K1500_Sub because they work far better with R134a.
Inspect the rubber AC lines, replace if they aren't up to *****.
New receiver/drier.
New orifice tube.
New low pressure cycling switch.
New high pressure cutout switch, if you keep an R4 compressor. They tend to be difficult to remove from the compressor housing.
R134a conversion fittings
Whatever PAG oil the compressor manufacturer specifies.
AC flush of some kind to purge the evap core.

That should be a good start

 

[351FUN]

Compressor - Sanden conversion is preferable, but NEW is the only way to go. No reman.
Condenser - Parallel flow as suggested by 1998_K1500_Sub because they work far better with R134a.
Inspect the rubber AC lines, replace if they aren't up to *****.
New receiver/drier.
New orifice tube.
New low pressure cycling switch.
New high pressure cutout switch, if you keep an R4 compressor. They tend to be difficult to remove from the compressor housing.
R134a conversion fittings
Whatever PAG oil the compressor manufacturer specifies.
AC flush of some kind to purge the evap core.

That should be a good start

Fantastic post, thank you.

 

[Erin]

I bought an AC Delco from rock auto. It crapped out in a year. Warrantied it for another. It crapped in less than a year, both times the pulley got stiff. They ended up refunding me.

 

[Caman96]

351FUN I tried looking on RockAuto but I don’t have all your Blazer info, like with or without rear AC. Also, just looking around I couldn’t find any GM Genuine compressor’s other than remanufactured which I personally wouldn’t get.

 

[Dariusz Salomon]

I would replace the condenser with a parallel-flow type.

The old R4 compressors tend to be noisy and tend to leak. I would consider a Sanden compressor retrofit. Brackets are available, etc.

The choice is yours.

Good luck!

X2

 

[Caman96]

X2

I just looked on Sanden site and I don’t think they make a compressor for a 92 Blazer. I think it said for 96 and up.

 

[Dariusz Salomon]

I think you missed the part where I said I don't even know all the parts I need to change lmao



That sounds super convenient, didn't even know it was an option.

One shop also said something about the lines needing to be cleaned out, can I just pull them and rinse them or blow them out?

I didn't either when I had to do mine but it's not that complicated-there's only few parts in ac system really unless you have rear ac-I don't know if 2 doors even had them tho. Go to rockauto and put your year/model and it will show a list of parts. Then just do the "id puzzle"-lift the hood and find the parts. Browse the net-read other forums(check silveradis too as ther will be more info but system should be the same mostly).
Shane your system doesn't work at all cause one thing you MUST do is to refill it with DYE-and it will show you where it leaks(get black light torch-easier).
So the course of action imo is:undo all pipe connections-replace seals-get the orifice tube out and check for signs of metal-if none you can get parts that are missing and install-replace dryer even if present-try to get it to run-refill with dye-see where it leaks-replace leaking components and refill-give it a week or 2 for some pipes to die and start leaking-replace and you should be ok.
As to cleaning lines you should do it if you find any signs of previous compressor desintegrating but you may do anyway-flush em-blowing may not be enough.
Hope this helps.

 

[Dariusz Salomon]

I just looked on Sanden site and I don’t think they make a compressor for a 92 Blazer. I think it said for 96 and up.

mhmm-not great as their design is way better

 

[Dariusz Salomon]

I found this tho

 

[Dariusz Salomon]

346002 - 1991-93 GM Truck Sanden AC Compressor Upgrade - Small Block V8

Replace your power-robbing R4 compressor with a Sanden-style compressor upgrade that requires less power to operate, runs smoother, and weighs half as much as the original units.

www.classicindustries.com