Flush hydraulics with diesel fuel?

[RalphVa]

Someone mentioned using a "slightly lower viscosity" fluid. That's diesel, folks. It's next lower boiling on the boiling point tree. The hydraulic fluid seems to be 5w oil, which is sent to the diesel pool if it is not used for oil manufacture.

If you really have water, flushing with diesel makes sense. Not sure just how you'd do it though. Need something that would connect with those fittings to the FEL. It'd flush with diesel, flow with air and then fill with hydraulic fluid. But you'd have to have the fitting the interfaces with those connectors on the FEL.

ULSD is actually pretty good stuff now, probably much better as far as not having any reactive compounds in it at all. The hydraulic fluid is very highly refined, too, but unless you got some that is water white, it'll probably have more contaminates than ULSD.

Ralph

 

[ishiboo]

Someone mentioned using a "slightly lower viscosity" fluid. That's diesel, folks. It's next lower boiling on the boiling point tree. The hydraulic fluid seems to be 5w oil, which is sent to the diesel pool if it is not used for oil manufacture.

If you really have water, flushing with diesel makes sense. Not sure just how you'd do it though. Need something that would connect with those fittings to the FEL. It'd flush with diesel, flow with air and then fill with hydraulic fluid. But you'd have to have the fitting the interfaces with those connectors on the FEL.

ULSD is actually pretty good stuff now, probably much better as far as not having any reactive compounds in it at all. The hydraulic fluid is very highly refined, too, but unless you got some that is water white, it'll probably have more contaminates than ULSD.

Ralph

No. Diesel is a MUCH lower viscosity fluid. I'm sure the poster meant a slightly lower viscosity HYDRAULIC fluid.

I'm not quite sure why you think flushing with diesel "makes sense". Diesel is not hydrophilic, so when you fill up your system this MUCH lighter weight oil stays in the same places as the water would. It's also not hydraulic fluid and provides MUCH less lubricity.

Drain a new sample of hydraulic fluid and send it in for analysis if the water test does not give you the answer you need. If it's still high in water content, check all places water could potentially get in, drain completely with the fluid HOT (work it baby!), and replace with fresh new fluid.

Though... I believe the MINIMAL amount of potentially trapped water from the last flush is diluted to the point where it's not relevant, and there are other problems at hand.