Hydraulic fluid venting - Jinma 284

[RonMar]

My problem is the wrong fluid was used in the machine and its foaming, previous owner used ATF instead of hydraulic fliud and every once in a while itll spit pink foamy pepto bismol out that spout.

ATF IS hydraulic fluid... It might be a little thin for this application though. You might be leaking air into the suction side piping that is helping create the foam. On mine, there was a pipe union right where the supply line to the pump comes out of the reservoir. That union was loose and would allow air to be injested into the system when running causing foam and jerking operation. The union had only the barest hint of fluid around it though. Pressurizing the system at the filler with compressed air will show it as a leak plain enough.

Once that union got snugged down, no more foam...

 

[SPIKER]

ATF IS hydraulic fluid... It might be a little thin for this application though. ...

Mentioned this prior that ATF was a good choice for colder climates. I had forgot about the pressurizing the hyd tank thru the vent and looking for leak in the suction line tho

 

[jbrukardt]

ATF IS hydraulic fluid... It might be a little thin for this application though. You might be leaking air into the suction side piping that is helping create the foam. On mine, there was a pipe union right where the supply line to the pump comes out of the reservoir. That union was loose and would allow air to be injested into the system when running causing foam and jerking operation. The union had only the barest hint of fluid around it though. Pressurizing the system at the filler with compressed air will show it as a leak plain enough.

Once that union got snugged down, no more foam...

interesting. No risk of damaging anything by pressuring the filler? How much pressure did you put on it, just a couple of pounds with a loose fitting or did you lock it down with a mashup of fitting that fit a compressor tube into the filler tube threads?

 

[RonMar]

It shouldn't take much, you should be able to apply enough with a rubber nozzled air gun tip squirted against the vent hole in the filler cap. I don't think you can apply too much pressure that way...