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Topic Review (Newest First)
05-04-2019 05:51 AM
Molon Labe I just finished a rebuild on my DeVilbiss 60 gallon compressor that has literally thousands of hours on it. I was seeing some foamy oil in the water when I drained the tank at the end of the day. Although the rings looked fine I replaced them along with the reed valves and gaskets. I had the crank polished while I had it apart too. The whole shooting match was less than $100 and it runs like a brand new compressor now. Much quieter and quicker to build pressure.

If you decide to replace the rings (and I strongly recommend you do) be sure you run a hone in the cylinders to break up the glaze. The only thing special about "compressor oil" is that it's a straight 30 weight oil without any kind of detergents in it. If you run a detergent oil you'll get a heavy carbon like build up on the reed valves which will eventually cause them to not seat properly. Ask me how I know.
09-01-2016 03:07 PM
BuzzLOL Reed valve upside down... glad to hear it... figured it was something simple now... should have wiped the oil off... it was from overheating and pumping without building up the pressure that usually keeps the oil below the rings...
09-01-2016 02:38 PM
mitmaks Had valve plate reversed, took it off and reinstalled and compressor is building up pressure now and shut off at ~125psi like its supposed to. Is there supposed to be oil on top of cylinders? When I took off valve plate it had a bit of oil on it.
08-31-2016 11:38 PM
TubeTek Part 0001 is the valve plate with gaskets
Part 0012 is a ring kit for one piston

The valve plate and 2 ring kits would be about $113. The complete NS18S pump is $204. If that is the pump it uses, the complete pump would be a far better way to spend your money as compared to buying the parts for the old one. If the rings are shot then you'd likely need to run a hone thru the cylinders to break the glaze and assure new rings would seat. Honing requires that you completely disassemble the compressor. Otherwise, junk from honing will end up in the bearings on the crank and they'll be gone soon too. Spend the extra 90 bucks, bolt it on, and your compressor is essentially brand new.
08-31-2016 08:20 PM
mitmaks Here's website that has parts for pump and where I've ordered gaskets from.
What's the part I need to replace?
BelAire B2800, B3800, NS18S & 4116091337 Air Compressor Parts
08-27-2016 05:00 AM
deadbodyman valves and ring and another gasket will fix it. Think of it as an engine with no compression theres only three things that could be wrong, you've eliminated one of them. but I've never seen one blow a gasket.
since its not an oil less comp its most likely the flap valves because they are usually thin metal that warps if they get too hot and lose thier seal so when you pull the head off place your hand or something over the cylinders one at a time to see if its got compression at the cylinders if not you need a ring also. I can tell by the blued head the valves are toast last pic of post 10 ,they got very hot so if your lucky you only need valves. but it will need valves. check the compression at the cylinder with the head off and you'll know if you need to order a ring.
08-26-2016 11:27 PM
mitmaks Installed new gaskets and it still wont build up pressure.
08-16-2016 06:11 AM
deadbodyman Yeah, every day when I leave I turn off the main and shut EVERYTHING down. then turn off the air tank valve. when I come in I turn on the valve and the breaker and get going. Sooner or later a line will bust so you really need a shutoff valve, plus it'll save a lot of cash not having the compressor start up and build pressure every morning of every day, not just in electricity but wear and tear of the compressor.
08-15-2016 08:30 AM
S10xGN One thing I always do whenever I'm gonna be away from home more than a day, I turn my compressor off. I'd hate to think what would happen if a line blew and that 7.5 HP motor kept running trying to make it up. I keep seeing the garage going up in flames...

08-15-2016 06:22 AM
deadbodyman Looks like your flap valves are toasted to me. replace them while its apart.
07-30-2016 02:46 PM
mitmaks Just ordered new gaskets, hope it will solve it. Cleaned up tops of pistons as well from carbon.
07-30-2016 02:42 PM
BuzzLOL Gaskets and re-torquing the bolts will prolly fix it right up... looks like you were lucky...
07-30-2016 02:21 PM
Originally Posted by BuzzLOL View Post
Not sure what I'm seeing... is something broken in that 3rd and 4th picture?
Copper (I think its copper) gasket must've oveheated and blew apart. I wonder if I should apply new gaskets and reassemble it or I need to swap out valve plate?
07-30-2016 02:20 PM
BuzzLOL Not sure what I'm seeing... is something broken in that 3rd and 4th picture?
07-30-2016 01:37 PM
mitmaks I've taken head cover off and found this
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