Mounting air compressor pump/motor to new tank

[nafterclifen]

Paid $100 for a Sears 4hp 20 gallon air compressor a few months back. Made by Devilbiss in 1984. Appears to be all original. Got it home, cleaned it all up, changed the oil and tightened some fittings. Worked great, no leaks and was super happy with its output and noise coming from a 6 gallon pancake.

Unfortunately, the tank had a TON of water in it when I bought it. In hindsight, I should have walked away from it and not purchased it. Lesson learned. Because now a pinhole leak has developed. I'm NOT going to repair it. I've even stopped using the compressor. But I'm not willing to completely junk it.

I purchased a new 20 gallon tank and plan to mount the existing pump and motor onto it and I'm looking for ya'lls input. I do NOT want to weld ANYTHING.

My current thought is cut off the mounting plate from the old tank and bolt it to the handles of the new tank. Using some 90 degree fittings, I hope to extend the plumbing to a near original location which will allow to me re-use the existing plumbing, pressure switch, etc

What say you, almighty Garage Journalites?

PS - if you think I'm wasting my time replacing the tank and think I should just buy a new complete compressor, I challenge you to find one that puts out 7.7 scfm @ 90psi for less than $500. At the moment, I'm only into the compressor and new tank for $265.

 

[cvairwerks]

Move the plumbing and bolt a flat plate onto the handles that's big enough to carry the plumbing and a remote drain too. Easier to make it fit where you need to and not have to kludge stuff instead.

 

[SJW]

So you seem quite clear that you don't want to repair the tank on the Craftsman, but I have to ask why?

The unit looks to be in pretty good shape. Why not get the Tank thoroughly cleaned on the inside--the rust and whatever else that is in there that shouldn't be, then patch the leak?

Just seems easier than replacing the old tank with the new one.

 

[bamawildcat]

I agree with your plan. Cut the existing plate off the old tank, cut off the mountain ears and bolt to the new tank. A can of gloss black, and it would look factory.

Or return the tank, JB weld the old one, and connect it via PVC so we really have something to discuss.

 

[rsanter]

Sorry bud but you are looking at the all the wrong way.
What you have is the opportunity to make something way better than it was before.

If I was in the same situation, I would do one of a few things.

1. Remove the plate with motor and compressor from the old tank.
Build a box that will hold the tank and the compressor+motor. Plywood will be fine. You can do some sound insulation and such and you don’t have to mount anything to the new tank. The benifit is that you will now have a boss with a top that you can use for something instead of the space above it being wasted.
Add shelves to the top.
Add drawers to the top.
Put a toolbox on the top.
Use it as a workbench.
Etc.

2. The same as above but you can build a vertical box in the corner.
Stand the tank on end. Remove the mount the compressor motor below the compressor pump.
If you have a dead corner that this can be a great upgrade for you


3. The other thing that comes to mind is that you can now reclaim that space on your floor to use for something else.
Make a shelf high on the wall, mount that plate with compressor and motor to it using rubber insulators.
Mount the tank remotely like in the rafters

 

[bamawildcat]

So you seem quite clear that you don't want to repair the tank on the Craftsman, but I have to ask why?

The unit looks to be in pretty good shape. Why not get the Tank thoroughly cleaned on the inside--the rust and whatever else that is in there that shouldn't be, then patch the leak?

Just seems easier than replacing the old tank with the new one.

A tank is a pressure vessel, aka missile, aka shrapnel generation device. You don't want to risk your health over something with such dire consequences.

 

[SGKent]

why are you asking? You are telling us what you have decided to do. Yes, it looks like you could bolt a plate to the top of the handles, paint it black, transfer the holes and move the compressor and motor over. You could also cut off the old plate and move it but you might need some spacers. Welding the tank is not a safe idea. I own two of those type compressors. There are many variations from Devilbiss that look alike, and parts are getting harder to come by. That said they work well for light jobs but don't make enough pressure to paint, glass bead etc. That is why I have two in tandem.

One of these might or might not make it easier next time. Photo is from ToolPartsDirect.com who sells them. Summit Racing sells them too. $175

 

[nafterclifen]

Or return the tank, JB weld the old one, and connect it via PVC so we really have something to discuss.

This made me laugh, thanks!

 

[nafterclifen]

Sorry bud but you are looking at the all the wrong way.
What you have is the opportunity to make something way better than it was before.

If I was in the same situation, I would do one of a few things.

1. Remove the plate with motor and compressor from the old tank.
Build a box that will hold the tank and the compressor+motor. Plywood will be fine. You can do some sound insulation and such and you don’t have to mount anything to the new tank. The benifit is that you will now have a boss with a top that you can use for something instead of the space above it being wasted.
Add shelves to the top.
Add drawers to the top.
Put a toolbox on the top.
Use it as a workbench.
Etc.

2. The same as above but you can build a vertical box in the corner.
Stand the tank on end. Remove the mount the compressor motor below the compressor pump.
If you have a dead corner that this can be a great upgrade for you


3. The other thing that comes to mind is that you can now reclaim that space on your floor to use for something else.
Make a shelf high on the wall, mount that plate with compressor and motor to it using rubber insulators.
Mount the tank remotely like in the rafters

I appreciate the thoughtful insight. The biggest limiting factor in my garage is space. And although you are right...I could potentially optimize the configuration with a custom box, shelf, etc...the setup of other stuff like my cord reel and hose reel (both are above the compressor, not shown in pic) and garage door really cut down on my options. I'll take another look though because I like your ideas.

 

[nafterclifen]

why are you asking? You are telling us what you have decided to do.

I'm asking for input because although functionally my plan should work, I have concerns that the two handles that are welded to the new tank might not be strong enough to support the load and forces of a running pump/motor. I guess I should have put that in my original post, oops.

Thanks for sharing that other tank option. I agree that it would probably be easier. Almost identical price too! $175 shipped for that CH tank compared to the $165 shipped that I paid for the IA tank. Bought the IA tank from Zoro so returning it shouldn't be an issue.

 

[larry_g]

3. The other thing that comes to mind is that you can now reclaim that space on your floor to use for something else.
Make a shelf high on the wall, mount that plate with compressor and motor to it using rubber insulators.
Mount the tank remotely like in the rafters

This was my first thought also. The receiver and the motor/pump do not have to near each other. Put the tank out side and the pump inside if necessary. Just don't place things so that they cannot be serviced and the tank drained.

Looking at your picture it seems that your already doing the above. Just cut away the red tank and then place things where convenient.

lg
no neat sig line

 

[CraigStu]

Wow, I can't help but am in exactly the same situation w/ a Craftsman compressor I have owned since new in about 1984. I have no problems but recently read about a tank exploding. I don't understand why it doesn't just develop a leak like yours. Any way I had the same problem. Seems that 7.7@90 is not popular now. Either around 4 for $4-500 or jump to 10-11 for near $1k. Thanks for the tank sources guys.

 

[dagofast]

I bought that same black CH replacement tank from Toolpartsdirect.com for my old 20 gallon blue tank CH compressor about a year ago. It is a direct bolt up for a CH but if you are using your different pump and motor, be prepared to drill some holes and possibly source another longer or shorter V-belt as need be.

BTW, you can get a new 20 gallon compressor for about $300. Keep on eye out for a sale at TSC for their Porter Cable unit. I also picked up one of those for added capacity and to keep one unit on 120V and portable.

Edited to add link: https://www.tractorsupply.com/tsc/p...rtable-belt-drive-air-compressor?cm_vc=-10005 And it appears to be on sale right now. Slightly less rated CFM. 5.5@90psi.

 

[nafterclifen]

Wow, I can't help but am in exactly the same situation w/ a Craftsman compressor I have owned since new in about 1984.

Upon initial review, that CH 20 gallon replacement tank is the obvious choice to replace my current tank because it has mounting plates already on it. However, my motor will not mount without modification. Might want to check yours too.

Here is a pic of the motor mount. You can ignore my custom tank dryer. I wanted to get it nice and dry after cleaning it. That little Metro Blaster worked real good.

 

[clinebarger]

A tank is a pressure vessel, aka missile, aka shrapnel generation device. You don't want to risk your health over something with such dire consequences.

Not the first time I've heard this (Dramatic music plays in my head), In all my years being a auto mechanic & being around several rotted out compressor tanks.......All I've ever seen is pinholes form that result in leakage.

I'm sure there are situations/circumstances where this can happen.....But was overpressurization the main reason?

 

[The Cobbler]

that tank you have is an air pig isn't it?
I don't think they have a drain on the underside of the tank, do they?

 

[nafterclifen]

that tank you have is an air pig isn't it?
I don't think they have a drain on the underside of the tank, do they?

The Industrial Air 20 gallon tank (model IT20ASME) that I purchased has a 1/4 turn drain valve at the bottom.

 

[kbs2244]

There is no law that says the motor/pump has to be anywhere near the tank.

My sons tank is under the dead corner of his workbench(with a remote drain set up) and the pump in the attic.

 

[givemethewillys]

I'd personally like to hear about what materials one would use to pipe from the pump to the tank. Al-Pex? Copper? Black iron pipe fittings? I put a pump from a 20gal compressor on an 80 gallon tank, and sort of retrofitted the line. It is now leaking and I would love to "do it right"

 

[dagofast]

You'd melt the Al-pex. The air coming out of the compressor head is hot as hades. Stainless steel or copper would be best. I've used soft copper in the past with no problems.

 

[nafterclifen]

I'd personally like to hear about what materials one would use to pipe from the pump to the tank.

Steel Braided Transfer Tubes appear to be an good option. Not cheap though.

https://mastertoolrepair.com/transf...94_434.html?osCsid=2uh67em13aksk3861jagu5c1nj

 

[Stuart in MN]

Not the first time I've heard this (Dramatic music plays in my head), In all my years being a auto mechanic & being around several rotted out compressor tanks.......All I've ever seen is pinholes form that result in leakage.

I'm sure there are situations/circumstances where this can happen.....But was overpressurization the main reason?

The thing is, if there's a pinhole there's most likely a much larger area of the tank wall around that pinhole that's paper thin. You'd end up just chasing more pinholes if you tried to weld it.

Air compressor tanks can explode, I've seen one that did in a residential garage. Fortunately no one was hurt, but it did a number on the car that was parked next to it.

YouTuber Mr. Pete222 / Tubalcain did a video some time ago where he cut apart a compressor tank that had developed a pinhole, to show what the metal looked like from the inside. It was a pretty good demonstration of what happens, and how thin the metal gets.

 

[MushCreek]

I've got the same situation with my little Emglo wheelbarrow unit. The replacement tank is serious money. I like having a portable compressor, though. I'm torn between buying a tank like the one shown and rigging up wheels, or just part the thing out (I could use the motor) and buying a little cheapie unit for the odd times I need a portable. The good news is that I only paid $100 for it, and built my house and barn with it, so it doesn't owe me anything.

 

[SGKent]

Most of the original Devilbiss units had two ears on the tank plate that a long bolt went thru. The motor had a bracket welded to it that sat into those ears and was held by the long bolt. Those ears and the bracket acted as a pivot that let the weight of the motor hold tension on the belt. It isn't a glorious design because it requires the Devilbiss tank and motor to work unless some modifications are made. Most likely to make the simplest swap, one would drain the old tank, grind off the welds for the top plate, and figure a way to cut and weld, or fabricate ears to weld to the new top plate. That would handle the motor side, something might need to be done to the pump side too. Alternatively one could cut the top off the old tank and fabric ears to it, then put it on rubber mounts somewhere near by and run pipe to the tank.

What surprises me is that with the millions of these things sold there doesn't appear to be a over the counter solution to this. Someone a week or so ago was trying to find the correct pressure regulator for one and non were to be found. The ones available are plumbed wrong. We live in such a disposable age. This forum is a throw back to times when people fixed things rather than tossed them.

 

[kbs2244]

MY son had a 10 foot piece of 3 inch pipe that he used as the vertical.
(It works well as a cooler. The drain is at the bottom of this pipe, not the tank itself.)
Top and bottom connectors are 24 inch pieces of 1 inch air brake hose he got from a truck parts store.

 

[marinusdees]

Not the first time I've heard this (Dramatic music plays in my head), In all my years being a auto mechanic & being around several rotted out compressor tanks.......All I've ever seen is pinholes form that result in leakage.

I'm sure there are situations/circumstances where this can happen.....But was overpressurization the main reason?

Me too. Explosions require the presence of an explosive mixture. Air is not an explosive mixture. Will it burst?? It may. More likely will rupture, scaring the sh-t out of anyone within earshot. Even more likely will slowly develop an increasingly large hole, still weldable. Would I weld it and use it?? Absolutely. I'm only 81 years old, and waiting for the boo birds to damn me to H--l. Ask me if I have used PVC for air lines. It may get me yet. I'd bet on some arterial catastrophe. I am not a pressure vessel expert, just a dumb Dutch farm boy from Michigan.

 

[Stuart in MN]

Me too. Explosions require the presence of an explosive mixture. Air is not an explosive mixture. Will it burst?? It may.

Semantics. Strictly speaking, an air tank that turned inside out so it looked like a big metal potato chip ruptured, but it still made a pretty loud bang when doing so.

 

[SGKent]

https://www.google.com/search?q=air...UIESgB&biw=1408&bih=750#imgrc=bYU3wS9xj_D7xM: