Giant air compressor Info, Saylor Beall?

[RobBob21]

Picked up this compressor at a farm auction a few years back and intended to put it together, but found a nice 1970s Speedaire that has been our main shop compressor. Now need a larger compressor at home so have regained interest into finding out more about this thing. Looking at pics online a Saylor Beall 705 looks the most similar but without a tag or numbers I can find I cannot tell for sure.
It is the largest non vee compressor I have ever seen, It feels like it weighs 200lbs and has a 18inch flywheel. Sorry for the low quality pictures I have yet to pull it out of storage:

I think the peerless motor and tank were in the same lot, don't remember where they came from:

Thanks for any help! I've got a lot to learn about air compressors and systems

 

[Jswain]

Definitely some version of a 705 / clone.

Great pump, many manufactures Sanborn sc23, webster etc. should be able to find parts easily if needed.

 

[driftpin]

I like my gen-yoo-wine Saylor Beall 705, try setting that in operation and see what it turns into.

 

[Jswain]

Just one thing to note, if it is Saylor beall then typically only Saylor Beall parts fit. Valves/internal parts etc.

Clones may or may not be interchangeable with other clones.

Could try sending Saylor beall a photo and asking them as from what I remember usually, but not, always the Saylor Beall will have their logo right on the pump.

 

[yatg]

looks like there's a number cast on the crankcase 4048R
that corresponds to a 705

https://www.saylor-beall.com/wp-content/uploads/20SAY011_700SeriesManual-Online.pdf

 

[kams1973]

If the fasteners are SAE, it’s most likely a Saylor-Beall 705, 5hp two-stage pump….and yes , it’s a heavy sumbuck at 225lbs.

This one has head unloaders that can be deleted if your going to power it with an electric motor.

the folks at Saylor-Beall are always very helpful when I call them.

 

[RobBob21]

If the fasteners are SAE, it’s most likely a Saylor-Beall 705, 5hp two-stage pump….and yes , it’s a heavy sumbuck at 225lbs.

This one has head unloaders that can be deleted if your going to power it with an electric motor.

the folks at Saylor-Beall are always very helpful when I call them.

Thats what those things on the top are? Could this unit have been originally gas powered? It would be a lot more useful to me if it was gas powered. I Think I would need a main unloader valve and a "bullwhip" to idle the engine up, but not sure on what parts I would need or where to get quality ones.
What direction does this compressor need to spin? and what size of motor does it need? I have an awesome Wisconsin engine that needs a job but not sure if it would have enough power. Thanks!

 

[American Locomotive]

Thats what those things on the top are? Could this unit have been originally gas powered? It would be a lot more useful if it was gas powered. I Think I would need a main unloader valve and a "bullwhip" to idle the engine up, but not sure on what parts I would need or where to get quality ones. What direction does this compressor need to spin? and what size of motor does it need? I have an awesome Wisconsin engine that needs a job but not sure if it would have enough power. Thanks!

The things on the top are unloader towers. Air pressure is applied to them and it unloads the compressor. Yes, a gas-application would have used them, but they'd also be used for "continuous run" electric applications as well.

 

[RobBob21]

I will try and tear it down some more over the weekend if I have time. It looks like I will have to make a tool to get the valves out of the head, I have seen some posts here on how to make the tool but I hope they aren't too stuck. What do I look for with valves? How can you tell if they are worn out? Sorry for the bombardment of questions, thank you to everyone that replied!

Here is that speedaire compressor I mentioned earlier, the mint green paint is awesome! (I know a pallet is probably not an ideal base)

Edit: I forgot to mention that we use these air compressors primarily to blow off equipment, we don't use air tools much anymore. Our farm equipment is old and its best if the radiators get blown out once a day.

 

[Shoreline_]

Best not to disturb the valves. Roll it over by hand if everything feels good just run it.

 

[kams1973]

Thats what those things on the top are? Could this unit have been originally gas powered? It would be a lot more useful to me if it was gas powered. I Think I would need a main unloader valve and a "bullwhip" to idle the engine up, but not sure on what parts I would need or where to get quality ones.
What direction does this compressor need to spin? and what size of motor does it need? I have an awesome Wisconsin engine that needs a job but not sure if it would have enough power. Thanks!

The flywheel serves as a fan to blow air toward the pump for cooling. And yes, constant speed or gas powered units use the unloaders. If memory serves me correctly, the gas powered engine should be 1.5 times the HP rating of the compressor head. I used to buy parts from aircomparts.com and mastertoolrepair.com.

This is an older unit based on the straight slot valve cover on the head. Regardless, parts are still available.

 

[RobBob21]

Didn't get to mess with the compressor much over the weekend. I've been trying to get the head off since I think there is a broken stud but one bolt is holding me up. Do these unloader valves just screw off or are they pressed in somehow? I thought I could get the bolt out without removing the high pressure side unloader but thats turning out to not be the case.
What are the head gaskets like on these? Is it frowned upon to copper coat it (or anneal it) and reuse them if they are not in bad shape?

 

[kams1973]

Here’s a the ver

Didn't get to mess with the compressor much over the weekend. I've been trying to get the head off since I think there is a broken stud but one bolt is holding me up. Do these unloader valves just screw off or are they pressed in somehow? I thought I could get the bolt out without removing the high pressure side unloader but thats turning out to not be the case.
What are the head gaskets like on these? Is it frowned upon to copper coat it (or anneal it) and reuse them if they are not in bad shape?

Here’s a picture of a head without the unloaders. I’m not positive how the unloaders are attached. They screw in on other older compressors I’ve worked on. (Not SB)

The gasket will probably break up when you get the head off. I’d replace it if you’re going to put any effort into this project.

 

[kams1973]

Here’s a SB publication. Shows the unloaders screw into the head.

https://www.saylor-beall.com/wp-content/uploads/2025/07/SB-7OPS-Saylor-Beall-700-Series-Manual-1.pdf

Also worth noting. Older SB units have cast iron connecting rods. If replacing the bearings, you’ll need to specify which rods are in your pump.

 

[RobBob21]

Thank you Kam, those unloaders were screwed in like you said they would be. They used some pretty good gaskets on these pumps, tapped on the head gently but could not get it off. Finally stuffed a rag down the valve hole and used the piston to jam it off.


Pistons and bores look really good, lots of crosshatching still left. I feel bad about tearing the head off since everything was in good shape but I had no idea the history on this unit or if it had sat outside. I think I might pull the side cover but that will be the furthest I go. Seems like I cannot just get the head gasket and need to order a whole kit.

Any advise on getting that tank tested? Thanks

 

[Jswain]

You can make your own gasket.

Order a bit of Garlock 3000(or equivalent, klingersil makes some nice stuff) gasket material and 5 minutes tapping with the round end of a ballpeen hammer. For all the other gaskets around the pump cheap felpro karropak of the correct thickness would be what I would use. Splurge for the better stuff for the head gasket tho

For testing the tank if you have a pressure washer or grease gun you can do it yourself. Tank needs to be 100% full of water to be tested safely. Hydro testing is what it's called lots of info on this site if that interests you.

 

[kams1973]

Thank you Kam, those unloaders were screwed in like you said they would be. They used some pretty good gaskets on these pumps, tapped on the head gently but could not get it off. Finally stuffed a rag down the valve hole and used the piston to jam it off.


Pistons and bores look really good, lots of crosshatching still left. I feel bad about tearing the head off since everything was in good shape but I had no idea the history on this unit or if it had sat outside. I think I might pull the side cover but that will be the furthest I go. Seems like I cannot just get the head gasket and need to order a whole kit.

Any advise on getting that tank tested? Thanks

I have one in my gasket collection if you want it.

 

[RobBob21]

Order a bit of Garlock 3000(or equivalent, klingersil makes some nice stuff) gasket material and 5 minutes tapping with the round end of a ballpeen hammer. For all the other gaskets around the pump cheap felpro karropak of the correct thickness would be what I would use. Splurge for the better stuff for the head gasket tho

I was going to ask if I could do this but wasn't sure what material to use, I love making gaskets. That Garlock stuff looks pretty pricey, I found some Equalseal material that seems to be a good price but I don't know much about heavy duty gaskets like that. 1/32" seems to be the thickness people recommend but need to read up on gasket material more.

I have one in my gasket collection if you want it.

Thank you! I will Pm you if that is what I decide to do.