Yes I see your oil fill off to the left, but I can guarantee, you’ve got some kind of allowance for venting of the crank case. I can go to any Home Depot compressor and the oil fill is typically a vented breather cap.
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I actually did piece together a vent plug and I’ll post pics later, but it didn’t work as that oil gets thrown around in there pretty good, and before long I had oil oozing out the cap vent slots leaving a big mess. These were the parts I used- a brass 1/2” bsp to 3/4” NPT adapter then a hydraulic CCV that has 3/4” NPT threads. The adapter was sealed to the case with a dowty seal-
Yeah so this didn’t work. For now I’m using the original vent cap that I super glued together hoping that it would get me by till Alkin got me the correct replacement part
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You may try adding a thin disk, like milk jug material, between the brass Adapter, and the plastic vent cap. poke a tiny hole in the disk to block slinging oil.
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Yeah I saw yours awhile back, when you sent me pics, that yours is plugged with no vent. Is yours a gas or electric model? The only reason I ask is I’ve looked at all kinds of Alkin compressors of my model year and I’ve never seen just a plug. In fact my owners parts manual shows my original vented cap(but they don’t list it as a part with a part number)On my "Old School" W31 there is No "Breather" /Vent cap or fitting...
Yes there are the small tubing connecting the crankcase to the Intake (behind the filter)
Then there is the tube connecting the 3rd stage cylinder to the oil fill extension neck.
But the Cap is solid and even has a Dowdy washer for a seal.
The tubing system is acting like the PCV on your car!
I maintains a Negative Pressure in the crankcase....
So any blow-by in the pistons system is routed to the intake of the compressor..
Also it establish there will no pressure build up to blow out any seals.
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If that don't work, maybe a brass plug, with the 1/2NPT extended 2", on the 2" extension, counterbore a hole with an oring in the bottom of it, add a stainless ball and a spring, then a set screw to capture the spring and ball, drill a tiny hole in the set screw.
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It is the 220Vac version.....
Just as long there is a tube connecting the crankcase into the intake... that means there will be no pressure build up... to blow a gasket...
So there is really no need for a 'Vent".....
Stuart
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@Ca_Varminter That I can understand. On mine I see that the intake is on top of the first stage cylinder. There is also a plastic tube running from the top of the first stage cylinder to the crankcase. Perhaps that’s the purpose of the tube.
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Yes it is.... Since there is No actual air/vacuum pump... they just use the negative air pressure behind the air filter..
This just enough to keep everything inside where it belongs!
Stuart
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@Bigragu
I know nothing about 3D printing or engineering at all. But, I wonder if someone could use a 3D printer and make you a new vented cap that would work, based off the original? Just thinking out loud here. With folks like Orion Iguana hunter, Stud Mag loaders, and Black Arts Design already 3D printing airgun magazines and other accessories, it might be worth a conversation with them.
I know nothing about 3D printing or engineering at all. But, I wonder if someone could use a 3D printer and make you a new vented cap that would work, based off the original? Just thinking out loud here. With folks like Orion Iguana hunter, Stud Mag loaders, and Black Arts Design already 3D printing airgun magazines and other accessories, it might be worth a conversation with them.
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This is what I was talking about earlier. I don't have a copy of the part so I can't reproduce it as my machine is electric.
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So, being the person that has always had a plan B to Z, especially when I quit getting the responses back from Alkin that I wanted to hear, I searched and searched high and low trying to find a cap with the correct threads, and to vent.
I totally get that maybe a standard brass plug would’ve worked, but there’s a reason that Alkin used a vented cap in its design back in 2004.
In my research, what I’ve learned is 1/2” NPT is rare in a compressor cap vent, and I felt the threads were more of a bsp. But nothing came up for compressor venting caps. After checking my measurements to thread charts I found this on AllieExpress, an M20 vented cap. I ordered two as they were cheap enough, and they came in yesterday.
After I unpackaged them I shook one of them and could here a tiny ball bearing inside. Must be the way it keeps oil from pushing out the top maybe, or some type of gravity check valve.
I am not one to use Teflon tape on threads on anything above an oil sump, or around anything that has to do with oil, really, and since Alkin used an o ring seal back in the day I went the better step and used a 1/2” Dowty seal and it sealed up to the case perfect.
I did 3000-4500 PSI top offs on two tanks, and no leaks or oil coming up the vent hole or out around the Dowty seal. I placed my fingers over the vent hole and air was quietly blowing out of that hole on top of the cap that could easily cause a piece of toilet paper held above to flutter a good amount. So with no leaks and doing what I feel it was designed to do, I’m going to call this vent cap I sourced a success, finally.
In case anyone with an older model Alkin accidentally snaps off their oil fill vent cap like this knucklehead did, I’m posting the link here on this thread so one knows where to buy. The threads on this one from Allie was a tiny bit too long when compared to the factory cap, but the thickness of the 1/2” Dowty seal took up that difference and sealed it perfect.
So my Alkin is now “back in the saddle”. This saying has always been true with me- you want something done and done right, you do it yourself!!
You can’t rely on someone else taking care of things for you. There are a few, and those are the exception, and those are the ones we let everyone know about.
It stumps me that Alkin could not source a replacement after telling me that in three emails, then telling me it’s going into design and production, when all I put in was a few hours on the net.
Link:
Two sizes are offered for this type, an M16 and the M20. You want the M20
I totally get that maybe a standard brass plug would’ve worked, but there’s a reason that Alkin used a vented cap in its design back in 2004.
In my research, what I’ve learned is 1/2” NPT is rare in a compressor cap vent, and I felt the threads were more of a bsp. But nothing came up for compressor venting caps. After checking my measurements to thread charts I found this on AllieExpress, an M20 vented cap. I ordered two as they were cheap enough, and they came in yesterday.
After I unpackaged them I shook one of them and could here a tiny ball bearing inside. Must be the way it keeps oil from pushing out the top maybe, or some type of gravity check valve.
I am not one to use Teflon tape on threads on anything above an oil sump, or around anything that has to do with oil, really, and since Alkin used an o ring seal back in the day I went the better step and used a 1/2” Dowty seal and it sealed up to the case perfect.
I did 3000-4500 PSI top offs on two tanks, and no leaks or oil coming up the vent hole or out around the Dowty seal. I placed my fingers over the vent hole and air was quietly blowing out of that hole on top of the cap that could easily cause a piece of toilet paper held above to flutter a good amount. So with no leaks and doing what I feel it was designed to do, I’m going to call this vent cap I sourced a success, finally.
In case anyone with an older model Alkin accidentally snaps off their oil fill vent cap like this knucklehead did, I’m posting the link here on this thread so one knows where to buy. The threads on this one from Allie was a tiny bit too long when compared to the factory cap, but the thickness of the 1/2” Dowty seal took up that difference and sealed it perfect.
So my Alkin is now “back in the saddle”. This saying has always been true with me- you want something done and done right, you do it yourself!!
You can’t rely on someone else taking care of things for you. There are a few, and those are the exception, and those are the ones we let everyone know about.
It stumps me that Alkin could not source a replacement after telling me that in three emails, then telling me it’s going into design and production, when all I put in was a few hours on the net.
Link:
Two sizes are offered for this type, an M16 and the M20. You want the M20
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Ok so with that comment im going to turn it around and tell you if I had to go out and buy another compresdor towards this hobby and if funds allowed it, back to Alkin for me! You, me, and everyone on this thread know these are the ones to own and are fortunate to own the best compressor out there for home fill of PCP’s.
What I’m disappointed in is I feel the search for my part sat on the “to do when I get caught up” stack at Alkin and someone dropped the ball, either because they didn’t give a crap, forgot, or was just too busy moving compressors out to folks like us. Im going to go with the latter on this one. I also would like to think the emails to me about them being busy searching for a replacement and getting together with engineering to re create the part wasn’t a stall tactic or just BS. So I’m taking the high road and saying they are just too swamped or understaffed
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My Alkin hose assembly is for connecting to foster fitting. If I buy a Scott or MSA SCBA tank, I there an adapter to fill the fireman style scba tank from my Alkin so that I don't have to buy an entire fill assembly?
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Yes- Air Tanks Plus has a female SCBA to male Foster adapter, and Air Venturi makes a female SCBA to male Foster adapter.
Most likely several others making/selling them too, but these are the two I have experience with.
https://www.amazon.com/Air-Venturi-Firehouse-Quick-Disconnect-Adapting/dp/B01N9OMJUH
https://airtanksplus.com/product/scba-hand-tight-fill-adapter/
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@Ezana4CE Thank you for your help in my quest here. Your input was / is greatly appreciated. And thank you to @Maher Kashoqa at Alkin. Happy Happy Happy !!
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