Flushing the Oasis

[newmarokie]

I have decided to flush the Oasis system. I pulled a sample and got it out in the light and it looks like weak coffee. It test to -18F for antifreeze/cooling properties. Using a digital ph probe the ph is 5.5(acidic) and the ph should be 9-9.5(basic). I plan to flush the system with fresh water thoroughly and then blow it out eith air to get the bulk of the water out before reintroducing the coolant. Does this sound about right to everyone?

 

[Richpatty]

Not sure you would want to flush water through....as I would not want any residual water in the system...which would be inevitable. I would think blowing it out might be enough.

 

[Rd1]

I did this once before, not sure about air blow, but here are the instructions I had, and it worked just fine. There was a video for this process, if I find it, will post.


You should drain the tank in the heater completely before purging by siphoning the fluid from the heater directly. Once you do this you don’t have very much of the old fluid left in the system. What ever is left in the lines will get pushed out when you are purging with the new fluid.

When purging, run the fluid from the return hose into a separate bucket until you see the fluid turn from clear/old to the color of the new fluid then put the return hose into the bucket of the new fluid.

To siphon the fluid from the tank in the heater; remove the hose coming from the fitting on top of the heater on the right side. This allows you to push the siphon hose all the way to the bottom of the tank. The fitting on the left does not go to the bottom of the tank and you can’t siphon from this fitting. There is about 8 gallons of fluid in the tank.

 

[Kevin D Pem]

I agree with the above posts! As I understand it, water degrades the fluid.

 

[Rustymayes]

How often does one do the flush? My reservoir in the engine bay is looking a bit wonky. Mine is a 2022 4081 with well under 100 hrs of burner time. The fluid still looks ok but the plastic reservoir looks dirty. I was thinking of at least removing it and washing it out and replenishing.

 

[newmarokie]

I have flushed the Oasis. I blew the system out with low pressure air. You can still hear the fluid in the tank slosh after the blow out. I removed the connection on top and siphoned the tank with a 12v diesel transfer pump. Everything was reassembled and I started filling the system with clean fluid. after 18 gallons, the fluid still hadn't cleaned up. I moved the suction to the return tank and let it circulate for about 20 minutes. The fluid now looks like weak tea. If I started this project with really dark fluid again, I would flush the system with water two or three times and then fill the tank with new fluid. Two to three gallons short of being full I would check the fluid and add concentrate to get the freeze point right. If the fluid looked good, I would omit the water flush, I know my fluid is good but it looks like a darker green ethylene glycol solution.