metal shavings in orifice tube

prof_chaos on Tue August 07, 2012 12:59 PM

Year: 1998
Make: Audi
Model: A6
Engine Size: 2.8
Refrigerant Type: R134a

Hi I'm a new user here. I am trying to fix the ac on my Audi after the compressor seized. I have a new compressor coming but I thought I should check for metal shavings/debris and I found some on the orifice tube:

Now I am wondering if it's ok to just flush the lines and replace the compressor, and maybe the condenser too, or do I need to replace everything? The evaporator in this car is very hard to get to so it's a huge job if I have to do that. But from reading up on the subject a lot of sources say if you have metal shavings it could ruin the new compressor and condenser, and therefore everything has to be replaced. It doesn't look that bad to me but I don't really know what the inside of the evaporator is like. Apparently it's a parallel flow evap and can't be flushed effectively.

Any advice on this would be greatly appreciated - would you risk just flushing the lines and installing a new compressor, and keeping the evaporator?

Cussboy on Tue August 07, 2012 2:35 PM

Disclaimer: I'm NOT an expert.

If it was mine, I'd backflush backwards with solvent from the orifice tube to where the compressor attachment is. Then blow out/dry off the solvent. The O.T. should've prevented particles from passing on to the evaporator.

However, if your condenser is the parallel type, then extremely difficult to flush/clean, as solvent will just go the path of least resistance, so in that case I think you better do new condenser too.

prof_chaos on Tue August 07, 2012 2:43 PM

Cool, thanks. Yes the condenser is parallel, but they are not that expensive and they are easy to replace on this car. I am pretty sure I'll replace it since it must have some metal in there if the o.t looks like this. The evaporator was my real concern since it is also parallel and so can't be flushed properly. Hopefully not much debris has gotten in there.

bueller on Tue August 07, 2012 7:17 PM

In our shop, that would require a full compressor job (compressor, drier/accumulator, OT, condenser, and full flush). We wouldn't warranty it unless it was done correctly.

prof_chaos on Tue August 07, 2012 7:56 PM

Quote
In our shop, that would require a full compressor job (compressor, drier/accumulator, OT, condenser, and full flush). We wouldn't warranty it unless it was done correctly.

Yep I am planning to do all that - what about the evaporator? Would you replace that? That is the only thing I don't know about. Everything else is being replaced, except the lines, which I will flush.

iceman2555 on Tue August 07, 2012 9:35 PM

Since you are performing the repair yourself and considering that the evaporator in this vehicle may be a multi-pass unit, why not change the unit. The system would then be restored to OE specifications and should give you many years of service.
The photo does indicate a bit of lubricant break down...the discoloration of the lube on the orifice tube. Total removal of this contaminate should be seriously considered. It may not be possible to adequately flush this from the evap. Also when compressor are 'dry' and the metal shavings begin to appear this normally indicates lubricant flow problems. The evaporator is a main source of lubricant storage when this occurs. The majority of the lubricant for this system will be in the evaporator.
Good luck!!!

-------------------------
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Thomas Jefferson

prof_chaos on Tue August 07, 2012 9:50 PM

Quote
Originally posted by: iceman2555
Since you are performing the repair yourself and considering that the evaporator in this vehicle may be a multi-pass unit, why not change the unit. The system would then be restored to OE specifications and should give you many years of service.

The photo does indicate a bit of lubricant break down...the discoloration of the lube on the orifice tube. Total removal of this contaminate should be seriously considered. It may not be possible to adequately flush this from the evap. Also when compressor are 'dry' and the metal shavings begin to appear this normally indicates lubricant flow problems. The evaporator is a main source of lubricant storage when this occurs. The majority of the lubricant for this system will be in the evaporator.

Good luck!!!

Thanks...There certainly is some discolored oil in the evap, I noticed this when I pulled the inlet line.

The only reason for not wanting to replace the evaporator is that it's a huge job on this car to get to it. All the other work I had planned (compressor, condenser etc.) is trivial by comparison. I will try flushing it and see what comes out. I'll consider replacing it depending on how that goes.