Sears/craftsman Air Compressor Oil In Air Tank

juiceclone

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Hi all I have a sears two cyl air compressor, probably 40 years old at least , about a 15 gal tank. . Dont use it a lot, It's on 3rd motor now and mostly runs/ran? well. A month ago I thought there was a lot of moisture coming out when blowing off parts etc. Turns out what was coming out was a chocolatey mix of water and oil. I have an auto drain on it and noticed that was sticking open. Removed the assy, found it gooped up....so I repeatedly filled and vented the tank. Same crap came out, but not that much really. Maybe a shot glass or so? Put it all back together and ran it a bit again. and found the same stuff coming out the nozzle. Seems like it's going into the tank as a fog or something and coming out as I use the air. Went to Harbor Fright and got a cheap replacement, and began to disassemble the sears unit. Cyl bore is perfect, bearings have no play. Thought I'd see really bad piston rings. The compression rings end gap is .015 and the oil control rings around .026. Does this sound excessive enough to be causing the oil to get into the head and out into the tank or not? (Crankcase vent is open) Could the oil rings just not be doing their job even if that clearance isn't excessive? I can,t think of any other excuse for the oil. Think I'll be able to find replacement rings, and maybe reed valves as well. Also, any good/safe way to get that oil out of the tank? Anyone have a similar experience?
 
my gut reaction was that it may be due to a very clogged air inlet filter, and worn valves causing it to work too hard, produce more moisture and suck oil from the crankcase. i would also consider that ring gap to be quite large. could you feel the vacuum sucking air into the crankcase vent hole ?
is this a twin cylinder ? probably a campbell hausfield if it is. 2-3 hp ? if so, i may have some parts for it hanging around. a pix is worth a thousand words.
I'm not a expert here but just thinking.
 
a set of rings, valve reeds and gaskets are pretty cheap considering the age and quality at the time that was produced. i would fix it if it were mine.
 
yeah...that's the direction I'm headed...but stalled right now.....had to take the Harbor Fright one back and get another cuz it did what HF stuff does so well. @#^XXxxxx
 
Does the bore still have any kind of crosshatch pattern or is it smooth and shiny? Mike
 
Likewise, feel for any ridge in the bore right at the top of each cylinder. For the shiny bore, you need a glaze buster. For the ridge, you need a ridge reamer. New rings in a glazed cylinder will not seat any time soon. And new rings with a ridge left at the top of the cylinder can result in breaking the top ring.
 
Initally, I would clean the tank with a solvent of some kind. Diesel fuel is what I would use personally. Then rinse with
warm water and laundry detergent or dish soap. If the unit has seen 3 motors, it is likely time for an overhaul of the
piston/bore area or consider getting a new or different compressor pump or even get a whole new unit. Also, it
would be a good idea to check the condition of the tank as it could be rusted thin. Tapping with a
ball pien hammer along the bottom will indicate weak spots where moisture has accumulated. If the tank is sound,
it would probably be worth it to rework the pump.
 
no ridge at top or bottom of bore ... no crosshatch remaining..smooth.... tank is a consideration, think I'll do a little exploratory banging and see what shape it's in...If I have to, I'll get another tank and build from there. I hate the pumps made today with compressor built into the end of the motor housing... they run at the motor speed with appropriate noise level, short life and inefficiency. Can't replace the motor on them either ....have to replace the whole thing...
? ?take bets on the reasoning why they're built like that??
Belt driven 2 cyl pump gives less obnoxious sound, works beautifully, and u can replace motor as needed. This thing is 40 plus years old with a 1 hp motor and will fill it's 15 gal tank in half the time that the HF 12 gal 2.5 horsepower one takes.
 
Do you know the model number? I have a Sears 2 cylinder, 30 gal compressor (model 919.176300) and found a copy of the owner's manual here: http://www.manualslib.com/manual/149948/Sears-176.html#manual
I picked it up for around $100 on Craigslist a while back and it works great. It puts out around 10 cfm@40 psi/7.5 cfm @125 psi and is very quiet. I believe the pump is made by DeVilbiss.
 
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