purging lube system with solvent

[madmachinst]

I was thinking of trying to purge out my lube system. I know I should change the restrictors and be done with it. Just someone said try a porta power unit with mineral spirits. Remove the tube from the one shot and put a 1/4" attachment on the porta power and try to shoot mineral spirits through the BP lube system. What can I end up breaking here?

 

[memphisjed]

I was not getting oil to the knee when I got my clone. Always trying simple first I ran a 1/2 bottle of sea foam thru the one shot (a few shots, who is counting?). Works on cars, worked on the mill. Never had to remove lines.

 

[Speedie]

NEVER USE SOLVENT. Best thing to use is pressurized kerosene.

 

[memphisjed]

Kerosene is a solvent.

 

[madmachinst]

would have thought mineral spirits is an oily and milder solvent than kerosene. Memphis Jed, kinda like your idea, just wish Creep came in liquid form would run that through system. Did wonders for my Lathe subspindle.

holy crap Memphis Deep creep is made by seafoam.

 

[AdamC]

If the metering valves are bunged up, I don’t see how mineral spirits with fix them. I think you will just force more pressure against the clogged filters until something gives.

whenever this comes up, I always wonder why the recommendation isn’t to force solvent in the opposite direction. But that would mean disconnecting every line and connecting it to pressure somehow to back flush.

so, having recently rebuilt one of these, I recommend replacing all the valves and any hose that’s questionable. Don’t spend another minute thinking about it. My 50yr old Bijur, works great with the new valves.

 

[M.B. Naegle]

Never tried a porta-power unit, but on a couple of mills I connected a pneumatic line in place of the one-shot pot and left it under pressure until I could hear air whistling out. Fill lines with kerosene or diesel and do it again. Each line does a separate way, so if you're not getting fluid out, then you know there's a problem. I don't know that I would recommend this as a preventative maintenance cleaning so much as a test to see if the system is working and where. If you already know that a line is plugged or otherwise not working, I'd rather take it apart to clear the line as there could be a chip lodged in there or a broken line.

 

[13engines]

During my many machine rebuilds I've looked up and into clogged oil restrictors. I don't remember now where I read or heard, but every time the word was REPLACE.

I don't recall them being terribly expensive. How many does a knee mill have anyway? 6-8??

If you're still nursing an ancient 5 gallon pail of Vactra oil, you might want to switch, as I also remember hearing about the wax in old Vactra being part of the plugging problem. I think it's been removed since. I'm a Shell guy these days.

 

[madmachinst]

I guess no substitute for taking it apart.

 

[johansen]

If the metering valves are bunged up, I don’t see how mineral spirits with fix them.(..)

whenever this comes up, I always wonder why the recommendation isn’t to force solvent in the opposite direction. But that would mean disconnecting every line(...)

The metering units have a one way valve in them that takes a certain amount of force to open, and a filter that clogs up.

You would be better off forcing kerosene through in the normal direction while heating the metering units to 400F.

 

[Dan from Oakland]

Just replace the metering units......... if the lines are plugged at the way surface itself, drill out a few older metering units reinstall them, and then blow solvent thru the system to flush the lines. I have never had any luck trying to unclog a metering unit. A porta power can build up enough pressure to blow lines out of fittings or split plastic lines if you are not careful.

 

[Modelman]

Ditto. I have an injection press with, I think, 55 meter units, most of which were plugged when I bought it second hand. I never had any luck unplugging them. They used a short steel pin in an accurately sized bore to meter the oil, Once the grit gets pushed through the filter, or grit backs up from the bushing running dry, it's all over. Just replace the meter units and while the lines are apart flush them with WD 40 or similar.

 

[Phil in Montana]

1..Best, take it apart, 2.. so so use atf and a porta power pump, You might blow the metering valve apart, but then back to the first choose...Phil

 

[AdamC]

Just a note about valve replacements: I did mine a few years ago and they were about $15/each. Some of the brass flare nuts were cracked, maybe over torqued. That led to replacement of those entire lines.

Depending on your patience for down time, budget etc, I’d either recommend replacing the entire line system or at a minimum, inspecting all your flare nuts before ordering parts.