Flushing Synthetic Hydraulic Oil to Replace with ISO 32

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I have a fluid coupling that currently has Fyrquel 220 in it. This is a synthetic phosphate ester fluid.

I want to replace this with a Shell Tellus 32, which is an ISO 32 oil.

I am under the impression that these two fluids are not compatible. How do I flush the synthetic prior to refilling with the ISO 32?

6/21/1012:00 PM

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robertcMember

The fyrquel complicets life.

It's going to leave residual phosphorous if you are not very thorough.

Which is not, by itself a problem.

I would start with a thorough wipedown of tanks, etc and then do a high speed flush with at least 10 system volumes of the new oil.

10 just popped into my mind, no idea if that is the RIGHT # or not, it's just what I would start with.

Disposal is gonna be an issue if you have just created hazardous waste by mixing.

Of course, a call to ICL (supresta) might be useful too

6/21/1012:46 PM

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erictr6Level 2 - 51 to 100 posts

Ted, They are definitly not compatible. Why are you changing from Fyrquel 220 fire resistant fluid to a mineral oil?

6/22/104:53 AM

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hussamadeniMember

Hi,

Fryquel 220, is a Fire resistant Hydraulic oil and would have been recommended for a "specific purpose." It is a PE - Phosphate Ester and probably hygroscopic as well.

As Robert, has indicated, it would leave residual phosphate and multiple flushing necessary. In the presence of moisture will form weak phosphoric acid and thus prone to rusting and corrosion. Will damage sophisticated systems like "Moog" valves.

How do you justify changing to a different category of oil?

Hussam

10/13/1011:49 PM

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