No "argument" from me, I have had possibly, all types of problem using these type of wood stabilization vacuum system, may provoke. From overfilling with oil to underfill, chamber too full (no much space to foam), from oil going into the chamber/juice (loss of Power) to juice being sucked into the pump and everything in between, I had a little bit of everything, most happened in the beginning but, not all...!
The oil I have been using for awhile is a redish colour (the same as a weak wine), and after clogging up the pump with some experimental liquids for dying, such as Methylated Spirits (please. do never use this stuff to dilute a dye and try pull full vacuum to colour your wood, bad idea).
Certain liquids when they get mixed, they tend to react in very strange ways, becoming "gouey" is the most typical, cleaning the pump thoroughly, is not a pleasant job...!
My pump starting to make that "rattling" noise, long ago, and there are no broken or loose parts in it, the noise comes and goes, I notice that, the harder the pump is working (chamber very full (16lt capacity) and after it reached its maximum vacuum, sometimes (not always) trying to maintain that full vacuum, the pump starts to rattle.
It does it with fresh oil, oil with water in it, oil with little use and with oil used a lot so, decided to not be concerned of how many times the oil was used but, remove as much water from the oil, before each time I need to start the pump and make sure, I have the oil level between the high and low.
The air here has lots of moisture so, is inevitable that water will form in the oil, most of our type of pumps have a little screw with an O'ring as the "bleeding" point, those are nasty to hold on to when you want to unscrew enough to let the water come out, the screw is just too short and fall down while the pump sump contents keep running out, by the time you find the screw and try to put it back into the hole (never seems to fit...), you lost the water and most if not all the oil, creating a big mess, in the mean time..>!
I resolved this by getting a threaded rod with the same thread as the screw with a plastic knob to make it easy to handle. The thread rod is about 1", using a 1mm drill bit I drilled a "vent" hole from the centre of the road (the end that screws first into the sump), in an angle (about 60°) to come out about 1/2 from the rod end, this way, when you want to remove the water out of the oil (always after the pump has been untouched for some hours so that the water can settle on the bottom) you simple unscrew the knob until the water starts coming out you still have plenty of threaded rod inside the sump so, it never comes out when you least wanted).
Tilt the pump at 45° from the end where the bleeding knob is and you will see the water coming out clear, and it will continue to do so until all water is out and the oil starts to come out. At this point you screw the knob back into place making sure an good O'ring is there to seal the knob properly. At this point, the oil can show a little lower than normal (always let some oil run out after the water comes out) so, you top up right to the level you had before.
I don't have a specific time or a number of goes before I completely drain the whole oil and replace with new, I do this about twice each year, and I do stabilize a lot. By allowing a bit of oil come out when draining the water, and replacing it with new oil, you are basically, replenishing the older oil and bringing back some of the new oil properties, allowing "things" to keep going, and working normally...!
Making a hole that small in the threaded rod, is not easy however, the greater difficulty, is not to brake the small drill bit, before the hole is through, this is here 95% of times the drill bit will snap so, if you get a few nuts that fit right, in the rod, covering well, the area where you planned the drill bit to exit, you not only wont brake the bit but, you have the nuts to use to mount in a vice to secure the whole thing...!
It works for me, obviously...!:wink::biggrin:
Cheers
George
