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Which hydraulic fluid is best to use ?

Hi , I just received my brand new yong heng 4500 psi compressor 110 volt that I bought on Amazon with a 4 year warranty! It is not a knock off brand it’s a yong heng . I want to put the best hydraulic fluid in it to prolong the life of the unit . It calls for iso VG46 , AW46 . Also says Mobil 827/829 or equivalent. I want to go more into a synthetic hydraulic fluid . What kind of hydraulic fluid would you recommend to use that may be better than the iso46 . Also would it be possible to use a premix antifreeze that has been chilled instead of water to cool the compressor? I’ve seen videos where water has caused corrosion inside the unit where the water flows to cool the heads . Wouldn’t the premix antifreeze help in the wear and corrosion of the heads instead of water ? 
 
This has been warned against and mentioned so many times. Please do a search on this topic.

DON'T put hydraulic fluid in a small compressor. It's made for hydraulics, not compressors. It stinks up the room when it gets hot. Hydraulic fluid leaves deposits which gum up the insides of your compressor and you'll need rebuilds much more often than if you use a quality non detergent compressor oil made for high pressure compressors. Rarus 827 is overkill, overpriced, and unnecessary.

Go to Filtertechs.com and get Secolube 500. Or buy Royal Purple Synfilm 100. Rarus 827 is $60 a quart for a $300 compressor. Don't waste your money on it.
 
lol oil wont matfer use a namebrand though not some dollar general crap .. the antifreeze is a good idea for the simple reason of corrosion protection at the disadvantage of you got a bucket of goo water laying around all the time ... my opinion, get yourself a can of spray pressure washer protectant and goose it out when your done and forget the bucket of goo water ...
 
This is what I’ve used for a cpl years in mine just keep it clean $8 a quart at a local Napa or other retailers 
85956173-70A9-477D-A1D9-AEC476365089.1616973042.jpeg

 
Edited and Current 12/01/21

Here is my standard post to all things Yong Heng hope it is helpful.

The Yong Heng "Simple" version least expensive does not have a water separator you need one.

If you messed up and got the “Simple” version you can get parts on Aliexpress to add it for <$40 or you can spend much more on a decent water separator and filter.

The "Auto Stop" version shuts off near 3000psi probly not a good thing for most people.

So you likely want the "Hardcover" or "Set Pressure" versions your choice on the 110V or 220V.

The 220V will run approximately 15% faster here in the USA as we run our 220V at 60hz instead of the 50hz found elsewhere. This may or may not be a problem depending on the compressors environment and cooling.

There is now a new Digital version of the Yong Heng out. I know little about it as it has not been around long enough but there is a review available and it looks to be a better unit than the “Set Pressure” model. The poor quality gauge, with the adjustable dial, on the Set Pressure version that failed every few months, has been replaced by a digital readout that gives much more information.

Review on the New Digital unit;



https://www.youtube.com/watch?v=rR0cdENjV8s&ab_channel=TargetForge



New "Smart Digital Version" 110V here

https://www.aliexpress.com/item/32863018900.html

New Digital version 220V

https://www.aliexpress.com/item/32815880523.html?spm=a2g0o.productlist.0.0.2ee360718xbmkY&algo_pvid=20abc6ca-c5fa-4bb8-bdf0-d13897a53109&algo_exp_id=20abc6ca-c5fa-4bb8-bdf0-d13897a53109-25

I am aware that shipping has gone way up and this is no longer the least expensive place to buy the YH but it will show you the different models so you know what to look for elsewhere.

https://www.aliexpress.com/item/32824234795.html?spm=a2g0o.store_home.productList_13760454.subject_2

Amazon now has a decent price and free shipping.

https://www.amazon.com/YONG-HENG/s?k=YONG+HENG

The compressors come with an assortment of o-rings and seals that are the most commonly used. So you should not need a reseal kit anytime soon.

You should check the tightness of all of the fittings and lines when you get it. That will save you from having to replace any seals right away.

The early teething problems with the pistons was taken care of years back so, they are very seldom a problem these days either.

Make sure you fill it with oil before you fire it up and after you do any werq to it that requires draining the oil.

Make sure you have the water reservoir plumbed and the pump turned on before you start the unit.

ISO 46 may no longer be recommended although I used it for a year without failure. I am currently using the Husky Brand Synthetic or synthetic blend oil, found at Home Depot, for two years now without a problem. Top it off to the red circle in the sight glass. This oil is clear so you can see when it gets contaminated.

https://www.homedepot.com/p/Husky-16-oz-100-Full-Synthetic-Compressor-Oil-018-0083H/300135698

I have heard of several compressors being badly damaged or destroyed by detonation. I would have to agree with heavy-impacts conclusion of low flashpoint oil getting past the rings of the first stage piston and into the second stage cylinder where it is ignited by high compression. So, using a high flashpoint oil, specifically made for high compression compressors, is likely the best insurance against this. This oil was suggested in another thread. It is a bit spendy but a quart will do three of your likely yearly changes so it’s not that bad.

https://filtertechs.com/shop/oil-media/compressor-oil/cl-581812-lq/

Never start them under pressure. I should have put this in here sooner.

Give them a dedicated 15amp outlet 20 would be better. They draw a bit of juice on startup especially the brand new ones. Don’t Use an extension cord unless it is short and has an honest 15+ amp rating. Preferably 12ga wire so you will not have problems.

Don't push your air fill past the compressor’s spec which is 4350psi. A little less is usually better than the max, and the Yong Heng should last for years unless you get a bad one. I do not fill past 4200psi as when I do, all too often, I blow a burst disc. This may not happen on the first or second fill but soon thereafter it will.

I actually found a restriction in my Tuxing filter that was causing the ruptured burst discs. I can now fill to 4350 or so without problems.

I did my first oil change at about an hour, it was extremely dark colored. I went far longer, between changes, after that.

I now have two YH compressors bought the second as a backup for the first as I fergot to turn on the coolant pump several times and overheated the first until it smoked. It did not like it but it continued to run just fine. Still I did not trust it after that. I added a switched outlet, to the system, so it turns the pump on before the compressor will power up to keep me from doing that from now on.

The second one, my back up unit, died in about two months bad QC from the factory. Cost me $12 for a new second stage piston and an hours’ time to replace it. Then to add insult to injury I fergot to put oil in, the latest unit after I put it back together, and ran it for several minutes without any. So, I filled it with oil and it fired up and somehow still werqs fine a year later. A testament to the oil it had in it before. The #1 unit that, I was worried about cuz I overheated it so many times, just kept on filling my guns and tanks till I got #2 repaired. The #1 unit got retired because it had the weak old style piston in it. I will replace that someday and have another good compressor.

The temperature sensor only measures head temperature so running it much over 20-30 minutes can overheat the motor and other parts even if ice is used in the coolant. Ice or a container of it, in the coolant, is a good idea especially if you are like me and do not use the full five gallons of water as suggested in the manual.

Keep your water supply level with the compressor to be kind to the pump and assure a good supply of coolant goes through the compressor.

I recently started using this Red Line water treatment after I noticed algae growth in my 2.5 gallon water bucket every few months. It seems to have stopped or significantly slowed the algae growth. I will know more in a few months.

Three months has gone by with no discernable algae growth so the water treatment werqs for that long anyway.

https://www.autozone.com/antifreeze-radiator-additives-and-windshield-wash-fluid/coolant-water-wetter-additive/red-line-water-wetter-super-coolant-12oz/486218_0_0

Keep your moisture filters, guns and tanks being filled above the compressor to help keep the moisture out.

Purge the system of moisture, using the screw valves on both sides of the compressor, for a couple of seconds every five minutes while in use.

Change out your small YH filter every twenty minutes and set the old one out to dry and reuse later.

Add a better filter if needed to be sure more moisture and any oil smell is removed from the system. Many of us use this Tuxing three media filter although, if you feel the need, you can change media types at any time.

https://www.aliexpress.com/item/32891898253.html

A smaller one will probly do for some in fairly dry climates.

https://www.aliexpress.com/item/4000960926898.html?spm=a2g0s.9042311.0.0.2a034c4dL0nrJU

Possibly a filter similar one of these, in addition to your desiccant filter, if humidity is high in your area and your desiccant filters have to be replaced often.

https://www.ebay.com/itm/30MPa-High-Pressure-Air-Filter-Oil-Water-Separator-For-Air-Pump-Air-Tank/402600939671?hash=item5dbce2d097:g:pRoAAOSwy41f00pY

https://www.aliexpress.com/item/33032569946.html?spm=a2g0o.productlist.0.0.56fc60ccm8gTGq&ad_pvid=20210607072408105818162084010006558357_1&s=p

Bleed the pressure before you turn the unit off and let it run a few seconds to get the better part of the moisture out of the system. I have found that I blow less burst discs if I bleed before shutting down so I do this religiously.

Let the coolant pump run for a few minutes after shutdown to cool things off.

I run the compressor in my 65 degree basement with humidity levels between 55 and 65%. Your purging times, filter and cooling requirements may be different than mine if your humidity levels and temperatures are not the same.

Just Yong Heng Info

In the manual the recommended amount of water in the reservoir is 5gal. Good for ten to twelve minutes or so of runtime depending on your compressors environment before you will need to shutdown to avoid an overheat.

Adding frozen milk jugs or ice will get you a couple more minutes of use before you need to shutdown to keep it from overheating. I shutdown at 60C and let the pump continue to run to cool things down.

Distilled water is not a good thing to use as it will eventually cause pitting in the aluminum parts exposed to the water.

Plain filtered water will cool better than water with antifreeze added. If you want less corrosion use Water Wetter. It will cool better than plain filtered water and give you some protection from corrosion as well. Although in my testing using watered down antifreeze 80% water 20% antifreeze vs Water Wetter I did not see too much of a difference.

Too much filter volume will cause one to have less fill time before the required shutdown so it will take longer to fill. But then again you will need to use the appropriate filter for the environment you are in. So, those in higher humidity areas will naturally have a bigger filter and less filling time.

You can use one way valves and shutoffs to keep the pressure in the larger filters to keep fill times shorter and lengthen the life of some compressors that have short lifespans.

I have needed a couple of these ferrules over the past three years as they sometimes do not survive once you have removed and reinstalled the high pressure stainless line.

There are other sizes on the other lines but this is the only one I have had fail on me.

6mm ferrules

https://www.belmetric.com/6mm-outer-hosebrdiameter-c-1041_1131_1143/



Here is some Information on the radiator install.

https://www.airgunnation.com/topic/yet-another-yong-heng-mod/?referrer=1

Here is a video on how to fill a SCBA tank.



https://www.youtube.com/watch?time_continue=157&v=_grx5p_R8D4&feature=emb_title




 
This has been warned against and mentioned so many times. Please do a search on this topic.

DON'T put hydraulic fluid in a small compressor. It's made for hydraulics, not compressors. It stinks up the room when it gets hot. Hydraulic fluid leaves deposits which gum up the insides of your compressor and you'll need rebuilds much more often than if you use a quality non detergent compressor oil made for high pressure compressors. Rarus 827 is overkill, overpriced, and unnecessary.

Go to Filtertechs.com and get Secolube 500. Or buy Royal Purple Synfilm 100. Rarus 827 is $60 a quart for a $300 compressor. Don't waste your money on it.

👍

That info is right on, disregard at your peril. I used top end mobile iso 46 in a Yong heng and it broke within a year. It will turn all green, it will stink and carbon everything up in the top end. Use real high pressure compressor oil.
 
Humdinger👍👍 https://filtertechs.com/shop/oil-media/compressor-oil/cl-581812-lq/ is a true diester synthetic 👍, the royal purple has 3 different bases, one of which is a hydrocarbon the other is an ester and a poly. which will work also. I look at the msds sheets

I have the Amsoil for a china compressor, then I bought a Coltri compressor, so I ordered a bottle of Ultrachem Chemlube 751ahead of time for it. Well the compressor came with a bottle of Coltri ST755 oil.

My point is use a good oil. read more about oil bases here

https://blog.amsoil.com/are-all-synthetic-oil-groups-the-same-group-iii-vs-iv-vs-v/
 
I’ve had YH compressors for over 4 years and never had either of my two fail. I watch these debates on oil and can’t help but laugh a little. Putting $60 oil in one of these is like putting premium gas in a Wizzard lawnmower and expecting it to turn into a Bugatti Veyron. The crankshaft connection to the driveshaft is metal on metal, and these are simple crude machines. They work wonderfully well but, putting anything better than a strait 30w non-detergent oil into one is expensive wishful thinking. Put some money into a good oil/water separator and change your oil often with something cheap.
 
I’ve had YH compressors for over 4 years and never had either of my two fail. I watch these debates on oil and can’t help but laugh a little. Putting $60 oil in one of these is like putting premium gas in a Wizzard lawnmower and expecting it to turn into a Bugatti Veyron. The crankshaft connection to the driveshaft is metal on metal, and these are simple crude machines. They work wonderfully well but, putting anything better than a strait 30w non-detergent oil into one is expensive wishful thinking. Put some money into a good oil/water separator and change your oil often with something cheap.

Proper oil is only 64 + shipping a Gallon. from Nuvair, Not 6 bucks a quart. Royal purple is just a few dollars less and is NOT designed for HP hair compressors. Period. If you don't believe it, call Royal Purple and talk to an engineer. 



Knife
 
I’m not saying anything about how much an oil costs or which is rated for what use. The piston rod connection is an aluminum alloy and the crankshaft is steel, no bearings. In the parts of the world where these are common place items they just use a 30w non-detergent oil and change it often. I change mine about every hour of actual running time. Easy to do and has kept mine working perfectly for over 4 years. Go ahead and pour the $$$ stuff in, just don’t expect it to perform some sort of miracle. Kinda like cars; more frequent oil changes are a better investment than expensive oil.
 
I’m not saying anything about how much an oil costs or which is rated for what use. The piston rod connection is an aluminum alloy and the crankshaft is steel, no bearings. In the parts of the world where these are common place items they just use a 30w non-detergent oil and change it often. I change mine about every hour of actual running time. Easy to do and has kept mine working perfectly for over 4 years. Go ahead and pour the $$$ stuff in, just don’t expect it to perform some sort of miracle. Kinda like cars; more frequent oil changes are a better investment than expensive oil.

Everyone has an opinion. And IMO, new users should listen to this one at their own peril. The oil lubing the rod/crank isn't the issue. Any motor oil would probably work as well as possible for that. The combustibility of the oil if it gets into the higher pressure stream is the issue, along with potential coking of the oil in the HP head due to heat. I change mine frequently but use quality HPA lube. Many others have suggested similar. But feel free to take your chances.
 
OIL-0024-QT-XL1.1617028217.jpg


Had a gallon of this left over from my Bauer dive compressor days. Been using it since the second oil change. First used the recommended iso 46. That oil came out dark, looking dirty/cooked after a short amount of time. The Bauer oil never comes out looking like that iso 46 did...

Some might not realize the extreme heat of compression generated in the YH. This heat cokes and carbons up the hottest parts of a YH, and most all HPA compressors. A build up of this coked up carbon under the reed valve will cause slow pressure build up and finally not able to build the correct pressure with valve being help partially open by coking deposits.... Unless the oil being used is specifically designed to avoid this type coking, it will happen eventually from oil blowby getting coked in the upper cylinder valve area. Over filling oil will make this happen much faster.

If anyone has taken apart a turbo compressor they can see the same coking build up that extreme heat causes.

As for the coolant use, well, use it if ya want but imo its not needed unless you're operating in freezing temps. Imo a much better choice is a water wetter that contains anti corrosion additives. More than likely the white deposits you see in ther utube vids calling that corroision is incorrect, thats mineral build up, very common in cooling systems when using a tap water with minerals. I use distilled with water wetter, and had no build up of any thing

jmo
 
Opinions are like butt holes. Everyone's got one. I agree totally with bandg and acs. I respectfully disagree with Air-Nashville for reasons reiterated by bandg and acs in their posts.

If an owner uses the proper type of oil, they don't need to compensate for improper oil usage by changing their oil every hour of run time. That's a PITA and a waste of money as well as false economy. The point isn't that the bearing wear on the crank to piston connection isn't improved by buying the correct type of oil. As stated above in my post above, bandg, and acs, it's the oil residue buildup that destroys the high pressure piston rings and burns leaving the check valves caked with carbon and unable to function. The damage occurs in the high pressure side, not in the crankcase. I rebuilt an Air Venturi for a friend who was using non detergent compressor oil intended for low pressure shop compressors. He also overfilled which aggravated the problem even further. I now regret not having taken photos to show the ecomony oil devotees what happens when heat and the wrong oil are combined.

Knife, you should check out Filltertechs.com. Compressor specific oils and cheaper than Nuvair. The Anderol 750 equivalent oil which Alkins specify and oils specifically made for each brand at prices from $15-20 per quart when purchased by the gallon.

Unfortunately, we will keep seeing "my compressor died" by owners who insist on following the hydraulic fluid #46 mantra or other bargain hunter alternatives. It's all great stuff until your compressor craps out on you.
 
I have done a bit of research on the benefits of, or not, of purpose-made compressor oils. I was told by the technical dept. of a performance-orientated and quality product oil company here in Australia, that the only substantial benefit of using synthetic base oil as compared to the mineral base is the extended change intervals 4000 hours against 2500 hours. They said that there was no significant difference in the flashpoint temperatures. The carbon and piston failures are caused by oil vapor finding its way past the first stage piston rings and past the cyclone trap into the high-pressure chamber and dieseling. The only way to minimize this is to not overfill and run on a level surface. So-called HPA lubricants sold by or recommended by the dive compressor companies use a nontoxic base as to not poison their customers. They are no less prone to detonation than any other quality oils. I see reports of I used this oil and turned a funny colour and broke my pump but they never mention what caused the breakage. Probably because ignorance was the real reason. AIR- Nashville's analogy is sort of valid. I would say it's like wearing a $500 helmet on a $5 head.
 
did I not say the exact same thing as bandg and scs, only a LOT sooner. I just checked the site you listed. Same price as the Nuvair by the gal. I will add them to my list. 

Thank You Humdinger.



I rally have to check my post and learn and try to understand just why people don't pay attention to my post when it is said by another and is then noticed. Odd!! 

I have writtenthis in MANT post on Many forums and most seems to go by unnoticed. Even by you. I feel like I'm beating my head against a wall. 



I have posted the pic of what Royal Purple or any other improper oil does to the valve and piston many times. Here it is yet again. The carbon
cdt4Z4r carbon from improper oil.1617066500.jpg
n build up can be easily seen where it both caked on the piston and under the reed valve. this allows back pressure back into the cylinder making pumping very difficult from the back pressure, and the carbon acts like a sandpaper in the cylinder.

cdt4Z4r carbon from improper oil 2.1617066479.jpg

 
I have done a bit of research on the benefits of, or not, of purpose-made compressor oils. I was told by the technical dept. of a performance-orientated and quality product oil company here in Australia, that the only substantial benefit of using synthetic base oil as compared to the mineral base is the extended change intervals 4000 hours against 2500 hours. They said that there was no significant difference in the flashpoint temperatures. The carbon and piston failures are caused by oil vapor finding its way past the first stage piston rings and past the cyclone trap into the high-pressure chamber and dieseling. The only way to minimize this is to not overfill and run on a level surface. So-called HPA lubricants sold by or recommended by the dive compressor companies use a nontoxic base as to not poison their customers. They are no less prone to detonation than any other quality oils. I see reports of I used this oil and turned a funny colour and broke my pump but they never mention what caused the breakage. Probably because ignorance was the real reason. AIR- Nashville's analogy is sort of valid. I would say it's like wearing a $500 helmet on a $5 head.

It is apparent that you have never researched the listed flashpoints of any of the different oil yourself, but rather rely on yet another second hand source. They are easily found. The statement you give above could not possibly be further from the truth. Members Follow his wisdom at your peril. 



Research us your friend!



Knife
 
It is apparent that you have never researched the listed flashpoints of any of the different oil yourself, but rather rely on yet another second hand source. They are easily found. The statement you give above could not possibly be further from the truth. Members Follow his wisdom at your peril. 



Research us your friend!



Yeah, I suppose you're right. The second-hand source that I quoted was only one of the technicians at Penrite oil that I spoke to on the phone. The pictures that you are using as an example are not unequivocal evidence of the wrong oil being used, only that some serious detonation has occurred and blown past the sealing washer on the top of the pencil piston. It may have been caused by wrong oil level, unlevel running, insufficient sealing of the oil rings on the first stage piston, or a combination of the above. The same thing may have happened with any oil, given the same conditions. The example that you use is not even a Yong Heng machine rather a Vevor that uses a different sealing method than composite rings of the YH. I know that the principals are the same but I thought that it was worth pointing out for accuracy's sake. I like many others have had a successful run of my compressor ( four years ) using generic mineral-based compressor oil bought from an auto-parts store and only changed once after the initial break-in period. The colour of the oil in the sump of a combustion engine means nothing about its condition, but with no combustion, there shouldn't be anything that would stain the oil other than moisture or powdered aluminium. My four-year-old oil is as clean as a whistle. If my machine was to fail tomorrow I would consider that to be a good run. Whether it was worth repairing would depend on what failed but I'm fairly confident that it won't be the big end. Too much research can lead to confusion and sleepless nights. Keep on banging.😁
 
Just learned something. I was always taught about the 4 things to never discuss, as it brings on confrontation-

1. Religion preferences

2. Political preferences 

3. Sexual preferences

4. Wages

i am now adding pcp compressor oils to this list.

hey, if oil is oil, and it didn’t matter, then let’s all use 3 in 1 in our vehicles!

All kidding aside, I agree with doing the research and soak in from “a reliable source” , use what is spec’d per a trusted manufacturer, and lastly buy the best you can afford. Heck, treat that compressor like you would that Daystate you purchased! 

What cracks me up is no one thinks twice about putting on an $800 to a $1K scope on a pcp, but thinks HPA compressor oil at $80 to $100 a gallon is too much!

ive always approached this hobby as the compressor being the lifeblood of it all. Guns, scopes, and anything thereafter are useless without the air.
 
Just learned something. I was always taught about the 4 things to never discuss, as it brings on confrontation-

1. Religion preferences

2. Political preferences 

3. Sexual preferences

4. Wages

i am now adding pcp compressor oils to this list.

hey, if oil is oil, and it didn’t matter, then let’s all use 3 in 1 in our vehicles!

All kidding aside, I agree with doing the research and soak in from “a reliable source” , use what is spec’d per a trusted manufacturer, and lastly buy the best you can afford. Heck, treat that compressor like you would that Daystate you purchased! 

What cracks me up is no one thinks twice about putting on an $800 to a $1K scope on a pcp, but thinks HPA compressor oil at $80 to $100 a gallon is too much!

ive always approached this hobby as the compressor being the lifeblood of it all. Guns, scopes, and anything thereafter are useless without the air.

Very level headed view, as usual. Hope you are recovering well.