I've just cleaned out the sump of a mill machine of around 10 gallons of coolant. Should I be worried about bacterial infection?

The only reason I'm asking is that the coolant had been lying in there for about 5 years and I noticed some kit in a nearby drawer which are basicaly culture slides to test for bacteria that you're meant to incubate for 24 hours at 30 deg C for 48 hours.

Once I get it clean (hopefuly in the next hour) I'll stick an aerating pump in the sump so that the anerobic thingies dun multiply, but how concerned should I be about this? is it a real health hazard or just crap?

How often should I be changing the coolant totaly please?

The testing things, if it helps, mentions Bacteria, Yeast and Fungis and has a 5 scale comparison for Slight, Moderate and Heavy infection.

Oh, the machine was left in this state by my predecessor and I wasn't too worried about coolant since I mostly machine plastics and ally, but I got this stainless job to do now and I assume I need coolant cos everyone says you do.

As long as you don't have any open wounds and used reasonable protection i.e gloves, I think you should be ok. Just be sure to get scrubbed when you're finished. I have done similar in the past and not suffered.

Coolant will usually last about a year I think? But I don't know of many companies that change coolant in a machine yearly due to the cost of disposal. It usually gets done when it really needs it. It also depends how often it is being used. If it is left to sit, then the bacteria gets a chance to grow.

Hi:
The way lubricant of the machine ends up in the sump.The bacteria in the cutting fluid thrive on the lack of oxygen. I've gone through this before.
1. If you envision using coolant more often, invest in a skimmer, to remove the tramp oil.
2. There are lots of coolants out there that are excellent at combatting this issue. 2 companies/products that we deal with are Fuchs ecoccool and Trimsol. The Trimsol is a really good all arount coolant, that is exceptionally good for it's longevity.I run a Test and Eval shop where sometimes a month or 2 go by without using a particular machine.
We check the coolant (make sure to top it up) once or twice a month.

regards

I've used regular household bleach, about 2 cups for 10 gallons.
It will kill anything in the sump and get rid of the stinkies.
I've never had a problem doing this.
Just be careful you don't get any on your clothes.

CC

One of my old working mates got really bad from coolant. Keep the tank clean!
CC:s tips is new to me, got to try it out!

--S

Gat a cheap aquarium pump and air stone. I put one on a timer and run it 1/2 hour per day to keep coolant aired out. I also run a skimmer off the same timer.

Then coolant lasts forever, just add new when low.

Karl