[attrezzop]

I'm looking for a liquid with a neutral ph that is typically non-conductive and won't react with polished aluminum, silver, gold, or lead. It needs to be about as viscous as water and the ability to evaporate. The ability to act as a solvent is undesirable but tolerable provided it won't react with the metals above. The more inert the better.

Distilled water won't work because as it absorbs salts or dissolves minerals it becomes conductive.

The goal is to use this liquid as a cleaning aid. Squirt the liquid onto a material to use it more like a physical brush to forcefully remove contaminates. Solutions for further cleaning will be selected depending on their need.

Cleap and commonly available, are of course, desirable but not required.

Any suggestions?

[Arkcon]

OK, this is kinda a hard problem to work with, so lets go point by point and try to get to the bottom of it:

I'm looking for a liquid with a neutral ph

OK, that's a clear, cogent, statement ...

that is typically non-conductive

annnnd, now, we've gone and left Earth chemistry behind.  Something non-conductive, that is non-ionic, won't have a measurable pH.  Not by pH meter, or reaction with indicator, or other acid/base reaction.  So, gasoline, or alcohol, or diethyl ether don't have a pH, or are pH neutral

and won't react with polished aluminum, silver, gold, or lead.

Ok, virtually nothing reacts with gold, and very few things react with silver.  Lead is pretty non-reactive too.  And aluminum is pretty non-reactive to common substances.

It needs to be about as viscous as water and the ability to evaporate. The ability to act as a solvent is undesirable but tolerable provided it won't react with the metals above. The more inert the better.

Distilled water won't work because as it absorbs salts or dissolves minerals it becomes conductive.

The goal is to use this liquid as a cleaning aid. Squirt the liquid onto a material to use it more like a physical brush to forcefully remove contaminates. Solutions for further cleaning will be selected depending on their need.

Why not use water?  Its non-reactive to all these metals, and as you flush, you'll dilute away the salts until its non conductive.  It evaporates reasonably well, its inexpensive and easy to source.

Are you using this to was something that is powered on?  You left that bit off, and that's what makes water a bad choice.  Can you not power down before washing?  Do you have any reason not to use alcohol, or ether, or petroleum distillate?

Cleap and commonly available, are of course, desirable but not required.

Any suggestions?

[Intanjir]

If you would use this to spray clean something then you probably need it to be quite cheap indeed. Beside this the requirement that it evaporate is a bit dangerous. Volatile organic solvents are in general large occupational and environmental concerns. I agree with Arkcon, water is probably the best choice for the bulk of the fluid.

Perhaps the conductivity can be sufficiently reduced by mixing with other solvents. Acetone comes to mind, being miscible with water but not sufficiently polar to dissolve most salts. Wikipedia lists the solubility of NaCl in acetone as 6 orders of magnitude lower than in water. A water/acetone mixture should be relatively effective at preventing or at least slowing the advent of conductivity from the dissolution of ionic compounds.

Acetone is fairly benign as far as volatile organics go and they exempted it from the VOC regulation to encourage its use over more noxious VOCs. However it very rapidly evaporates and can be a concern if enough was used in an enclosed space. However flammability and evaporation should be reduced some by being mixed with water.

Another idea would be to sequester the particular anions that encourage dissolution. Hydroxides are a lot less soluble then chlorides. It makes sense then to try to exchange chloride ions for hydroxide ions.
Alternatively one could just try and sequester both cations and anions, much as they do for making deionized water. A pH neutral mixture of suitable cationic and anionic polymers could perhaps be made to sequester smaller ions and yet not themselves appreciably conduct given their large size. However they wouldn't evaporate, and would need to be washed off if their trace contamination was a concern.

Anyways I kind of doubt any of this would be necessary. You are not working with particularly soluble metals.