More OBA Questions

[Wicked_Sludge]

i dont see how the compressors manage to last for a/c use if they wont hold up to OBA use...the problem would have to be with lubrication...maybe the wrong type of oil?

i dont know....when i finally get off my butt and finish my system i guess ill find out the hard way if i can get my compressor to hold out

 

[Sasquatch_Ryda]

Yea, I dunno, I've tried engine oil, ATF, air tool oil, you name it. All with the same results in the end.

 

[rickcdewitt]

at least the mounting pad for the wimpy sanden model would be easy to make an adapter on that could hold another compressor.but then you'd need to find one with the right serpentine pulley or maybe a serpentine pully for the 2.9l compressor?
-sasquatch, did your serpentine belt get smoked when the pumps seized?they are a little spendy i might just forget about my stock 91 4.0 ac pump right from the get go.

 

[Ranger44]

I think what we'd have trouble with is the "black death". Here's what happens:

These compressors were designed with Teflon coated rings. In time, these rings begin to "shed" which throws Teflon from the compressor into the condenser. This "shedding" begins to collect and trap the system lubricant, which worsens the shedding, and eventually enough of the Teflon is gone to allow the aluminum to rub the cylinder wall. This causes enormous heat to be built up inside the compressor, eventually hot enough to melt the aluminum and seize the compressor.

What you are left with, besides a seized compressor, is a black, gritty, gooey mess inside of the system. This goo, we call "black death", is normally trapped between the high pressure port of the compressor and the high pressure side of the orifice tube, however, it is slightly possible for some of the smaller particles to get through the filter screen, and cause deposits in the low pressure side of the system.

So what we need is to take these compressors apart and inspect the rings, and maybe replace them or find a suitable replacement that doesn't do the same thing.

 

[Wicked_Sludge]

when i had mine apart, i only noticed a very small amount of black goo...and only where there were metal to metal contact points (namely the "crank" and those little flat ball bearing things that the pistons ride on). my rings seemed to be in OK shape and the fit inside their bored was still snug.

so who knows, maybe mine will survive?

i have to think that at least one of the compressors sas has tried came off of a truck that didnt have a failed a/c system though...i mean what are the odds all of his compressors were on their way out when he got ahold of them?

 

[Sasquatch_Ryda]

The first compressor was the original to my truck and it worked fine, I wanted to have OBA more than I wanted AC was all. It died, I replaced it with one from the wreckers, it came off a system that was still charged and holding refrigerant, the one that I have in it now came off of a 92 explorer I bought for parts, the system was not charged, but it seemed fine. It isn't 'seized' but it makes some horrid noises when running even when lubed so I just haven't used the system for a while. I'm going to be trying to to fit the serpentine clutch off of the 4.0L compressor onto the 2.9L style compressor if I can't find a York for the right price. Withe the York I'd either have to find a serpentine clutch for it or put a serpentine pulley with an outer vbelt pulley on my alternator.

 

[Ranger44]

Thinking of an older 2.3 metal bracket or making my own custom bracket and actually using a York compressor or older a/c compressor and/or making a saginaw PS pump fit on this bracket too. We'll see. So much can be done with an imagination and work.

 

[JFA_Spyderman]

Yo,
On mine I use actual compressor oil. Mobil Rarus 427. Mine holds up well with no abnormal sounds. Here is a link. http://www.mobil.com/USA-English/Lubes/PDS/GLXXENINDMOMobil_Rarus_400.asp

 

[abaryth]

OBA Using Sanden Compressor

I welded up the stock holes after cutting off the pipes and just tapped the backside of the manifold using 1/4" NPT Pnufit "push to connect" fittings on all the components.

Tank mounted in the bed.

Engine Compartment.

Lubricator.

Pressure Switch set @ 120psi

Oil separator with spring loaded check valve.