Difference Between Aeration and Cavitation

[@bradball9065]

By far the best explanation I've seen! Thanks

[@hpt08]

Very useful for understanding the source of noise in my transmission!

[@edm9760]

What would cause a New Holland TC-18 tractor with a hydrostatic drive system to make erratic high pitched noises when cold, then go away when it warms up? It does not even make the noise when it is above about 60 degrees outside. It sounds like aeration but it goes away when warm like cavitation. Been doing this for 3 years now, I think I may have to change the hydrostatic fluid and see if that helps, I do not remember if the hydro fluid has ever been changed. Thanks for any input. Good video, very informative.

[@Gpmhydraulic]

Thank you for the kind comments! It can often be hard to tell the subtle difference in the sound of the two, particularly on mobile equipment. Changing the fluid certainly can't hurt, and if there is any water in your oil, it can make some strange sounds when it cavitates. A heater for your reservoir is not very expensive. If the sound goes away once the fluid is warm, I think it would be warranted.

[@vivekpandey841]

Sir solenoid valve ma malfunction kyo huta hai

[@gemma6472]

Thanks for your good work.. but I want to explain about oil smoke comes out from suction tank..why?

[@Gpmhydraulic]

Smoke? Or vapor? Vapor often forms in a reservoir as a result of water in the oil evaporating as the system heats up. You need to flush your system with a filter that can remove water. Keep it out using a desiccant breather. Smoke, on the other hand, is another matter. Something is threatening combustion of the oil and should be addressed immediately!

[@Musadiqbaig]

Hi sir good information i have problems with variables displacement pump, its sound during high pressure, even we replace new pump same type replace section hoses clamps too, still same pls help

[@Gpmhydraulic]

Well, assuming it's a steady sound, that would mean the pump is cavitating still. There has to be some obstruction in the suction line (or perhaps too small of a line). Also, make sure the RPM of the drive motor is within the specs of the pump. Check oil temperature - cold oil will do it, or the wrong oil (too high viscosity). Hope this helps!

[@PikeSlayer69]

Awsome thanks!

[@marekesz]

The dude maybe knows what he is talking about, but in the era of multimedia, on YT actually just talking about how should it sound or how should it look like is so weak... And the dude just can't wait to go have a leak (or maybe too much coffee in the morning) my eyes hurt from following him on the screen... Or maybe his trousers are burning - there's some kind of smoke behind... Anyway - the best he could do was taking the filter to his hand from the table and putting it back even without explaining what should we look for in this image... National experts... Pfff...

[@pharshal2007]

hi i am having trouble with a hydraulic pump.It's pressure sometimes becomes zero & when i restart the pump, pressure will get back to normal.

[@Gpmhydraulic]

Is this a fixed or variable displacement pump? If it is a variable displacement, pressure compensating pump, I would first check the compensator valve. They often behave in this fashion because of a pilot orifice in the valve spool. Cleaning this orifice usually corrects it. If it is a fixed displacement pump, the system relief valve is probably the issue. Hope this helps!

[@pharshal2007]

Hi thanks for the help it was compensator valve problem.I forgot to reply sooner .

[@HectorsCarAudio1]

Great video , great info 👍🏻

[@Gpmhydraulic]

Thank you for your kind comment!

[@vivekpandey841]

Nice

[@Gpmhydraulic]

Thank you!

[@vivekpandey841]

Sir my new fixed displacement van pump but sound creat

[@harrisonfowler4461]

I have a John Deere 318 and I believe the charge pump is cavitating. The tractor is very simple so there are no gauges or anything. The suction hose is 30 years old, but it's about a 3/4" hose. I've included a link to a video of it. Could you tell me what you think that noise is? This was in a relatively cold (40*) environment at a low idle. kzbin.info/www/bejne/p5qneYKLbN52bbM

[@Gpmhydraulic]

Hi Harrison - thanks for your comment! The sound in the video you shared seems pretty steady to me, and I hear no extraneous sounds that are usually heard during aeration so I believe it is cavitating. Since it was cold out, chances are good that the oil viscosity was simply too high. Did it stop making the noise once the system came up to normal operating temperature? If not, check the suction line for collapse or blockage and, if there is a suction strainer in the tank, check to be sure it is clean. Hope this helps!

[@harrisonfowler4461]

GPM Hydraulic Consulting thanks for getting back to me! This is the best description of cavitation I've seen on KZbin or anywhere else I've read. Nothing extraneous, just straight to the point. So thank you for that. It does quiet down once it's up to temp, but never goes away completely. I will be checking the suction hose. Also, I've had a few Deere enthusiast suggest that my filter (although new) could be airlocked because I didn't put oil in the filter before I put it on the transmission. Thoughts?

[@Gpmhydraulic]

Depends upon where in the system the filter is placed. If it's a suction filter, that's entirely possible. If it's a pressure or return line filter, it would be unlikely to contribute to the cavitation (though it is a good idea to fill the filter with oil prior to installation).

[@harrisonfowler4461]

GPM Hydraulic Consulting I think it actually is a suction filter just because of how simple the trans is. There's a suction hose from the bottom of the differential up to the bottom of where the filter screws on. Then the charge pump is on the top of the filter. The filter screws in horizontally, so I will do my best to get as much fluid in there as I can. I'll let you know how it goes.

[@harrisonfowler4461]

GPM Hydraulic Consulting I ran it for a good while. Heated up the oil. It's quieter. I also drained all the fluid out and it's full of tiny tiny bubbles. Not foamed. The suction hose at the bottom was perfectly clean and clean.

[@thelight888]

Awesome

[@vart7767]

Great video !

[@JackWeeks]

Thank you!

[@opieshomeshop]

Sorry Chris but you don't make me feel too confident about your company.