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Parts Cleaning fluid

I have been using simple green in my HF ultrasonic parts cleaner. Yesterday I noticed it was talking the protective coating(zinc?) off the hardware i was cleaning. Is there another cleaner/solvent i could be using to clean greasy parts that won’t strip the coating off?

I don’t know about an ultra sonic cleaner, but I got a gallon of parts cleaner mix at NAPA. You mix it with kerosene and does a good job as a solvent. I’ve never had a problem with Simple Green though. Its one of the best cleaners I’ve come across but you may need to dilute it more or soak it less. The only thing I soak for any length of time in it is buffing pads.

They say Diesel fuel will affect zinc also .Now if I cant wipe it acceptably clean , I use brake cleaner or wd 40 ,used to use "Janitor in a drum "old formula worked pretty good on grease ,somethings just dont really require OCD cleaning , some old mechanics in the asbestos heyday would replace the brake says and not disturb the backing plates to any great affect .A little sludge or film simply doesnt bother some things on the other hand dirt is a no no .
Harsh solvents are hard on biology .

My parts cleaner has nothing but 100% mineral spirits in it. I have a separate gallon can of Berryman for cleaning carbs and such. But everything else goes in the larger cleaner and no issues coming out pristine for the last 35+ years…

I would suggest that the Simple Green cleaner is not the problem but the HF ( assuming that stands for Harbor Freight ) equipment.

I’d personally use only a proper cleaning solution. There are a lot of different coatings used on car parts, including chromates, that might be affected by citric acids, so to me it makes sense to use the right stuff.

Zinc (galvanizing) and oxides should not be affected, but I’d rather be safe than sorry.

I bet that ultrasonic cleaner is only meant for water-based products. Time to find a less-aggressive one. How about dish soap?

I believe the ZEP solvent in my parts washer has been in there for over thirty years.

But then, anytime I use any solvent, brake cleaner/carb/throttle body cleaner, it’s applied to the part in the parts washer whenever possible.

So right now there’s an olio of solvents in the parts washer.


I agree that HF does not always have the highest quality stuff, and I make it a rule to never buy anything from them if it spins fast, but I don’t see how a sink with a pump from HF would strip zinc any faster than a sink with a pump from someone else.

Not a sink, an ultrasonic cleaner.

Ultrasonic energy could remove a zinc coating, gut it would have to be debonded first.

Dish soap sounds promising. If that doesn’t work I’ll try the mineral spirits. THANKS!

The parts washers I’ve used have always been filled with mineral spirits.

It’s not a parts washer. It’s an ultrasonic cleaner. @“Bad goat” - only water-based cleaning solutions can be used in most of those, so don’t use mineral spirits.

We use IPA and acetone in ultrasonic cleaners at work. The solvents are placed in a beaker with the parts. Disposal concerns would be the biggest reason to use aqueous cleaners in an ultrasonic bath to me.

The Harbor Freight cleaner is just a tub one dumps the solution and parts into, and the instructions warn against flammable solutions.

Ditch that ultrasonic cleaner and buy a simple parts washer. Mineral spirits never really wears out. I put a drain plug in it before first use if it doesn’t have one so I can siphon off the majority and only dispose of the solids. Then put it right back in there with a couple replacement gallons to offset the loss. It won’t readily evaporate and won’t harm painted or coated surfaces. There are more modern solutions but they cost more and IMO don’t justify the expense. The only reason I drained mine after 10 years was to move it to the new house…still running the same fluid.

I missed the ultrasonic part, but I still don’t see how ultrasonic waves generated by HF’s equipment would strip zinc any more than ultrasonic waves generated by someone else’s equipment.

You put the parts in a cup with the cleaner of your choice, and then you put the cup into the ultrasonic cleaning machine which is partly filled with water. The machine vibrates the water, which vibrates the cup and the cleaner inside. There is no way the manufacturer of the machine has anything to do with the problem of zinc removal. That’s because of some sort of reaction with Simple Green. Try something else.

I discovered Low Odor Mineral Spirits this summer after my wife swooned when entering the garage where I was cleaning bicycle parts in a coffee can of Mineral Spirits. LOMS costs more, seems to clean as well, and puts significantly less VOCs into the air.