Ingersoll-Rand Model 3-R-30 Radial Compressor


New member
I have a compressor my father gave me. He told me it was used to crank over airplanes during WWII. Other than the nomenclature I have no other information. I am interested in finding out where to sell it, or perhaps donate to a museum if it is worthy of that station. I have done a little research and found the carry wheel may be the bigger treasure. It does run.
Any information to assist me would be greatly appreciated.
Dad was very interested in all things steel, engine, gas pump, pumps, tools old and pretty much saved from loss from the earth.
He has passed away so I can not get information from him, the compressor is just sitting in a barn now.


Craig A

Staff member
Welcome to Stak....... :)

I moved your question to this forum where you might get some ideas.


New member
Those compressors, the 3R30 and 3R36, were primarily used in railroad applications. They most certainly did not start airplane engines. Airplane engines have electric starters, usually inertia type so the engine can be started from the operator's cabin. Think about it. If your airplane stalls somewhere out in the middle of the sky (probably over an ocean) would you want to wait for someone to come by with an air compressor to get you going again? Methinks not. Far better you just push a button and hope for the best. And even if the airplane engine had an air starter, that little compressor would not have the delivery to feed it.I think the whole airplane thing came up because the compressor sort of resembles an aircraft engine turned on its side.

An old Ingersoll-Rand catalog shows these compressors being used on various railroad projects and being lugged around by two guys. The catalog describes how many tools can be run from one compressor, drills, tampers, etc.

Yours is the smaller version, which is to the best of my knowledge the scarcer of the two. I've never seen one before. Yours will make 30 cfm at 80 psi. The larger machine makes 36 cfm, also at 80 psi. The lower pressure rating makes these compressors less than ideal for use with modern tools that are expecting 90 - 100 psi. These are extremely quirky machines and if you were looking for a compressor to use all day long every day you'd probably conclude that these are pretty awful, for a host of reasons. But that very feature, and the uniqueness of their design, make them great collectibles. You should have no trouble finding several interested buyers for yours. Heck, i have two of the 3R36's, one running and one in parts, and if you weren't half a nation away I would be very interested in it myself.

---------- Post added at 10:37:11 PM ---------- Previous post was at 10:31:43 PM ----------

Forgot to say, if you do decide to donate anything to a museum, check them out carefully before giving anything away. From what I hear, some museums are extremely poor stewards of the items left in their care. It'd be a shame to see something your dad enjoyed and probably owned for many years left out in a field to rot. I'm not painting with a broad brush here, I'm sure that there are some excellent museums out there that are extremely responsible. Just not all of 'em. Be sure before you do something regrettable.

Andrew Mackey

Same goes here - if you were closer to NJ, I would snap it up in a minute! You could always bolt it down on a pallet and ship by Fastenal! I bought my 3 R-36 for $125 at an auction. Still runs great and powers a few things very well. One thing, my unit makes 125 PSI, not 80. It powers up to 3 jack hammers, an air powered chain saw, and I use it to power a 4x6 steam engine I display at shows. It is noisy! As the original flattened pipe exhaust pipes were rotted off, I threaded the exhaust ells and installed B&S 5 HP mufflers. Nice and quiet now!!

Look in the Stak archives! There was a thread where a train museum out your way that was looking for a IR radial to do track work on their railway right of way. They might be still interested.

These units were a thirsty bunch! Mine will use the entire 3 gallon tankful in 4 hours under a heavy load! We used it to break up a concrete wall with the jack hammer, and cut RR ties to build a new wall. Boy Scout Eagle project!

Your carrier looks unique! The one I have pictured in literature is made of wood, has a single rubber pneumatic tire, and looks like a wheel barrow frame with 2 vertical stations that engage the pipe thru the engine frame that acts as a carrier. You place the uprights under the pipe and push down on the handles. The lever action lifts the compressor, and the frame and wheel carries the weight. On your carrier, the man handling it carries most of the weight thru the handles. Cool item!.
s100, would you have an extra wrap a rope starter assembly on your parts 3 R-36? The one on mine has a section busted out on the side, and as it is made of zinc, I cannot repair it. Thanks,


New member

I think there may be a conspiracy afoot.Both of mine have damaged rope sheaves.And while one of mine is in parts, it is one of my stated objectives to hear the thing run sometime before I die. Thanks to another kind member here I made a major parts breakthrough for mine recently, so I may clear off a spot on the bench big enough to hold the thing and start reassembly this winter.

I'm not surprised these are able to make 125psi, but they are rated by I-R at 80 psi, or at least that is what the catalog says. These things have something I-R called channel valves and it is my impression that these are not the most durable things made. And given the overall design idiosyncrasies of these things, and the lack of parts, I'm not going to push the issue. If you are getting 4 hours out of a tank of gas, you're doing great. The catalog brags about 2 - 2 1/2 hours continuous operation.

One thing I have hears about these, they want to overheat under heavy load on a warm day. Neither mine nor any others I have seen have any sort of sheet metal to direct the flow of cooling air, but the catalog shows some scoops to direct the air past the cylinders. Does yours have anything like that?

---------- Post added at 06:42:24 PM ---------- Previous post was at 06:41:15 PM ----------

Forgot to say, both of my starting sheaves are aluminum not zinc.


I have no idea what the value of one of these is, but you are about a 6-7 hour drive away, and it is an interesting piece. If you decide to sell it, I'd be interested.