Stinky coolant

[Straydog]

Hello all, we have 15 various different CNC machines and we are using Valcool vp-800p-275b coolant in all of them, only 2 of our machines the coolant starts to stink within 2 weeks after changing it. We've power washed the reservoirs rinsed with bleach water and still in no time starts to stink again. We are only running 5-8 hour days so the coolant isn't always moving like some shops. Has anyone had this problem and are there some additives that help with this or will bleach taps hurt anything to add?

 

[john.k]

Phenol is the traditional cure for bacterial growth.......by the way ,stinky coolant can be dangerous if mist is breathed,or if hands get infected by the 50 different pathogens you are breeding there.

 

[William Lynn]

Same two machines? Are these two getting water from a different source than the rest? Could you have spitters running these machines or be located close to an aisle way and someone is dumping leftover beverages? I have personally seen all of this done.

 

[Machinist Joe]

Had a similar problem at a shop I was at and it ended up being a fungus. Blaser kept taking samples and testing them saying there was nothing wrong but the smell, no bacteria. they finally figured it out when they saw a thin slimy film on the coolant. they said they don't normally test for fungus you have to ask for it. we gave them the boot and switched coolant.

 

[john.k]

The only machines with coolant were stinky,I swapped over to washing soda ,nothing can grow in alkali.

 

[Mtndew]

Go to your local pet store and get some cheap aquarium bubblers and drop them in the tanks, it will keep the coolant oxygenated and moving.

 

[Straydog]

Phenol is the traditional cure for bacterial growth.......by the way ,stinky coolant can be dangerous if mist is breathed,or if hands get infected by the 50 different pathogens you are breeding there.

Thanks I will look into the Phenol! I appreciate the warning as well!

 

[john.k]

Better check with the maker of your coolant if phenol is OK to mix .

 

[DouglasJRizzo]

A few things to mind:

If it's the same two machines, make sure that there are no hydraulic leaks. Leaky hoses can contaminate coolant fast.
Hygiene - I *really* hate to say this, but make sure employees aren't spitting or urinating into the tanks or dumping coffee/soda etc. At dad's shop, we had a large Daito saw that the coolant would turn bad in a week and the corrosion was unreal. A mystery until I caught the jack-wagon operator peeing in the tanks and spitting in them as well. Gross. After I kicked him to the curb, I cleaned it with sump cleaner, then hot water/steam and bleach.

 

[Straydog]

Same two machines? Are these two getting water from a different source than the rest? Could you have spitters running these machines or be located close to an aisle way and someone is dumping leftover beverages? I have personally seen all of this done.

Water source is the same, they are by the main isle and same operator for both machines which I have accused him of pissing in them Lol!

 

[Straydog]

Better check with the maker of your coolant if phenol is OK to mix .

I will thanks!

 

[Straydog]

A few things to mind:

If it's the same two machines, make sure that there are no hydraulic leaks. Leaky hoses can contaminate coolant fast.
Hygiene - I *really* hate to say this, but make sure employees aren't spitting or urinating into the tanks or dumping coffee/soda etc. At dad's shop, we had a large Daito saw that the coolant would turn bad in a week and the corrosion was unreal. A mystery until I caught the jack-wagon operator peeing in the tanks and spitting in them as well. Gross. After I kicked him to the curb, I cleaned it with sump cleaner, then hot water/steam and bleach.

No leaks just way oil to skim off, but I will have to keep an eye on him because it's the same operator for both machines!

 

[Straydog]

The only machines with coolant were stinky,I swapped over to washing soda ,nothing can grow in alkali.

Thanks John we may have to consider that!

 

[Straydog]

Go to your local pet store and get some cheap aquarium bubblers and drop them in the tanks, it will keep the coolant oxygenated and moving.

That's a good idea! We've thought that these 2 had less circulation than the other machines! Thanks!

 

[Mtndew]

That's a good idea! We've thought that these 2 had less circulation than the other machines! Thanks!

We have a few of them on our Okuma machines and it has worked wonders.

 

[MrWhoopee]

Oil skimmers and bubblers. The growth is usually anerobic bacteria, oil on the surface cuts off the oxygen. Nothing repels the wife more than the smell of rancid coolant. Reclaimed oil from the skimmers is great chainsaw bar oil.

 

[Bill D]

Would adding a zinc anode bar prevent biologicals from growing? Even just dropping in some old galvanized pipe cutoffs.
Bill D

 

[john.k]

I got shocking sores on my hands and wrists from stinky coolant.....like blind boils ......one time I got pneumonia when I was doing a lot of internal grinding,with lots of coolant fog from the high RPM spindle......and I always had at least one infected fingernail all the time.........Its too hot here to wear rubber gloves,they fill with sweat .

 

[john.k]

Copper is a better biocide than zinc.....dont know if it would work

 

[Blaser Swisslube]

We agree with other user comments that an oil skimmer and/or an aquarium bubbler would work. In general when tramp oil is the issue, we recommend try using a shop vac to remove tramp oil on top of coolant, ideally weekly. Hold the shop vac about 1 inch above the surface to remove the tramp oil. If you can, add an antibacterial agent to remove any bacteria that might be present, rinse well, and refill with new coolant at proper concentration.