Air compressor in cold weather

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Hi, this isn't really my first post. For some reason I couldn't get into my old account, and even the "forgot password" code didn't work.

Anyway, I am having troubles with my air compressor. Our old one has about an 8 gallon tank and a 2 hp motor, and it has lived outside for 15 years or better. It has not given any trouble even in the cold. I just got a 21 gallon tank 2.5 hp motor compressor from harbor freight and it wont even turn over in the cold. It was -6 F yesterday, which isn't cold at all by Minnesota standards. I even went as far as plugging it in right to the outlet without an extension cord, drained all the air, and left the valve open. Even then, it would just lope a couple times and the overload on the motor would trip. It is full of some mystery harbor freight oil right now, but even the synthetic sae 30 compressor oil I picked up is pretty thick. The manual states sae 10 is fine in the winter, however, I cannot find sae 10 non-detergent to save my life. I have heard of some regular motor oils like mobil 1 being used (not sure why mobil 1 would be more like non-detergent than any other brand
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). The manual clearly states to not use detergent motor oil of any kind. If mobil 1 is safe to use, do you think 0w-20 would be a good substitute for sae 10? I was also thinking of type F ATF. Compared to Mercon, it is low in detergents, and is similar to a 10w.

This compressor worked like a charm indoors, but it probably only has about 1/2 of run time. It says to change the break in oil after an hour.
 
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Could be it needs to break in more. Could you also have ice in it somewhere?
 
Personally, I don't see the need for non- detergent oil in air compressors. Mine is 30 years old and i use it a lot in the summer, and a fair amount in the winter, and have NEVER used non detergent oil in it. Book called for 10/40 and that is what I use. Of course, It never gets used in temps lower than about +20f. It is a cambell Hausfeld 2 cyl cast iron belt driven compressor with a 20 gal tank and a 3 hp motor. If I was using in below zero temps, I would probably use 0/20 or no heavier than 5/30 which is what I use in my snow blower. (5hp tecumseh)

BUT, if you really want sone 10 wt. non detergent, try a farm supply store.
 
There is no way it has ice in it. It sat idle for a day and then I moved it outside. I am fine with using motor oil, I just don't see why the manual states not to. Something about valve deposits. If I change the oil twice a year, why would it be a problem? As for the ATF, is there any issue in that? I don't have anything lighter than 5w30 (which still feels thick), but I have tons of type F and it seems like a great choice in these temps. I guess the better question is will it cause seal problems?
 
Motor oils and air compressors don't work together nicely. Motor oil additives can leave deposits on compressor valves, and compressors don't get the oil as hot as engines so the additive packages may not work as effectively. Also compressors put a lot of water vapor into the crankcase, and the condensed water needs to stay separate from the compressor oil and go to the bottom of the sump rather than turn the oil into a nasty emulsion.

I think online ordering is going to be your friend in getting a better oil (not that it will be able to save a POS Hazard Fraught compressor /motor combo). Royal Purple Synfilm 10 or Synfilm 22 might be a good starting point, just from an availability perspective.

I wouldn't go the ATF route, either.
 
So what does the average person do? I'm far from the first person who has tried to use an air compressor in winter temps. I've tried half a dozen stores, and they all sell compressor oil, but its all sae 30 or similar. Our little one works fine, and it just has regular air compressor oil in it. Is harbor freight that bad? The only thing I've bought from them before is some sockets, and they seemed better than Chinese craftsman. I don't expect it to last as long as an American made, high dollar compressor, but is 5-10 years really an unreasonable expectation?

P.S. I'm not paying $360 for that. I could go to Menards and get the same thing for the same price and made in usa. I paid $140 for this compressor.
 
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The real problem is likely that the pooptacular electric motor provided by Hazard Fraught doesn't have nearly enough starting torque for the job. Could be an undersized start cap, or just a sloppily built motor with too much stator/rotor air gap. Electrical stuff is not on my list of "safe" things to buy at Hazard Fraught, even though some of them do seem to be OK.
 
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Take a deep breath. Relax.

Of course your little compressor works fine. Why wouldn't it?

This, on the other hand, is a 2.5hp single capacitor motor that you're running on 115v. Obviously, it's going to have a difficult time in those temperatures.

You need to ensure that you're getting absolutely maximum current to the compressor; nothing else drawing a load on the circuit, and plugged directly into the outlet (no extension cord).

As Trav said, go get some 0w-20.

Originally Posted By: 2stroke
I'm not paying $360 for that. I could go to Menards and get the same thing for the same price and made in usa. I paid $140 for this compressor.


That's a belt-driven, twin-capacitor compressor for $360.
 
The other compressor just has a smaller tank, it still has a 2 hp motor running on the same outlet, and it looks to be a bigger compressor as well. I know its a lot faster. May be 30 seconds tops to go from 0-90 psi. My new one takes 2 minutes at least to get to 125 psi. I guess I just didn't believe harbor freight could be this bad. I kept hearing how good a deal there stuff was from a family member, and finally tried the place. The sockets seem great. I tried to drain the oil and its still coming out. In just the past 3 days, maybe 30 minutes of actual run time the oil has turned to a black goo. They use a machine screw for the drain hole, and its been draining for the past hour. I'm so disappointed. I have a feeling the thing is already locked up. I even went so far as to pull all lines off so all the motor had to do was turn the compressor with no resistance and it wouldn't do it. I will be returning this and will not be purchasing anything from harbor freight again.
 
Originally Posted By: 2stroke
black goo.


One more time, for emphasis...

This compressor holds 5.6 ounces of oil. That's it!

A quart of 0w-20, enough for five complete drain & fills, is $7 is Walmart.

If that's too much for you to do, then take the thing back.
 
Originally Posted By: 440Magnum
Motor oils and air compressors don't work together nicely. Motor oil additives can leave deposits on compressor valves, and compressors don't get the oil as hot as engines so the additive packages may not work as effectively. Also compressors put a lot of water vapor into the crankcase, and the condensed water needs to stay separate from the compressor oil and go to the bottom of the sump rather than turn the oil into a nasty emulsion.

I think online ordering is going to be your friend in getting a better oil (not that it will be able to save a POS Hazard Fraught compressor /motor combo). Royal Purple Synfilm 10 or Synfilm 22 might be a good starting point, just from an availability perspective.

I wouldn't go the ATF route, either.





Thanks for telling why motor oil isn't optimal in a compressor!
 
Some compressors have problems with cold start valves. Tractor Supply carries 10 non-detergent, but all I saw was Traveller in 2 gallon jugs. My local hardware store can get anything from their suppliers even if they don't stock it. Just have to wait for it, so you could ask if they can get it.
 
+1 on the 0W20 oil. I would also consider heating the compressor itself with a hair dryer or heat lamp and see if that helps a bit. The coldest I used my old Sears compressor was about 15F with straight 30 grade oil in it. It made a bit of noise for a few seconds but worked fine. I have semi synthetic compressor oil in it now, but haven't used it in the cold yet.
 
To get back to you guys, I'm sorry for the whining about the compressor. This is an oil forum. I've been doing research, and I have found a few sources that also recommend ATF. In fact, it would be a perfect oil if it didn't emulsify with water. I'll just be absolutely sure to change the oil every spring and fall. I'll run sae 30 compressor oil in the summer. I put Type F in it because I have a bunch and feel it is a better choice than mercon. It took a couple tries, but once the compressor broke free, it ran great again. I let it run a few cycles and it seems to be just fine. Time will tell if ATF will turn to sludge with water, but I keep a close eye on my things. I'll try a nice cold start later to see how it really does.
 
Don't use engine oil. If you cant find SAE 10w (or ISO 32/46) compressor oil, use HLP or HL hydraulic oil in the same grade. SAE 30 is like an ISO 100.
 
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I did manage to track down some sae 10 non-detergent, but the parts store was unsure how long it would take to get here. I found it online, but only in huge cases. Type F ATF has been working ok so far. It's still red, and the compressor starts right up.
 
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