My First Big Compressor -Craigslist Find-

[Mopar_Mikey]

Hey All,
Just picked up my first real compressor for my home garage. Maybe a little of overkill but I found an 80 Sanborn/Coleman 6.5HP 11.9CFM@100PSI 80 gallon on Craigslist last weekend for under $200.
My old Craftsman 4HP 20 gallon 9 CFM@40PSI served me well over the years but was just pushed to the limits.
I have a 68 Plymouth Fury III and a 1965 Dodge D200 I want to start aggressively working on.
With the old compressor I was able to lay down some marginal HVLP projects but needed something bigger for sand blasting and more painting. I'm a weekend warrior, nothing too extreme.
The compressor I picked up works good but I have to get some new parts for it. The compressor had been worked on before but the pump, tank, and motor are in good shape. The pressure switch had been swapped out with a 95/120psi switch and the relief valve was a 115psi. It does build good pressure up to the limit switch.
So far I have pressure washed it, put fresh oil in it, checked all the fittings and replaced as needed. Ordered a new relief valve, new belt (too small of course), intake filter/silencer. I need to find a good reliable vendor of pressure switches however. Does anyone know of a company called Industrial Equipment Expert on Ebay and Amazon? Seems like they may have what I need just not sure about some of the Tiwan (LEFOO) made products they sell. I'm not looking to put another $200 into this compressor but want to make sure it runs safely. I do not want to run a magnetic starter to start with, the specs on the motor say it's a 22AMP pull and the manual states it is not required. The factory switch is a 145/175 switch made by Furnas/Hubbell with no mag starter required. Also as said I replaced the drive belt (007-0034) which states it's a 60" and cross references to a Gates A58 1/2 x 60"..so that's what I ordered...ummm...did not follow my father's measure twice advice...Seems to get the belt on I have to push the motor all the way to the center and at that it still seems tight. Will these v-belts stretch much or should I just go a couple inches longer? It runs fine but just doesn't seem like it should be that tight. I just don't want to damage the bearings or bind something up. Sorry for all the elementary questions, it's just the first time owning a compressor like this. I'm posting a few pictures up of my new score.

 

[2oolhound]

Sweet deal! I'd follow your gut on the belt size, as long as it doesn't slip you're good of coarse. Nice find and there's no such thing as too big as long as you can fit it in.

 

[nine4gmc]

Stop by any auto parts store and ask to borrow their v belt stretcher, it's a free loaner tool.

 

[nine4gmc]

just kidding, that's an auto part store joke. You can mark a spot on the old belt and measure around for the length or cut the old belt and measure length that way.

 

[cvcman]

I like Condor pressure switches,,,great customer and tech service...

 

[evintho]

Excellent score! You'll never regret going bigger. To tight of a belt will put unneeded pressure on the bearings. Use a taylors tape to measure the belt size.



Any small engine repair shop should have the proper sized belt.

 

[bastage]

Nice Find... I went for months checking CL twice daily and the best I found on a 2 stage was a 60 gallon 6.5 HP 15.3@90 American Air (Develbiss) that they were asking 800 for. I talked them down to 500 & thought I did OK.. You on the other hand made out like a bandit...

 

[Mopar_Mikey]

Stop by any auto parts store and ask to borrow their v belt stretcher, it's a free loaner tool.

Good one!!! I work in the fiber optic deployment field...We actually have Fiber stretchers...we send the new guys to the supply house to pick them up along with aerial vaults. Just wondered if the one on my compressor started to be a 60" and stretched that much. I have plenty of play either way if I go with a 62" belt. Just strange that the factory size doesn't seem correct. Pulleys have not been changed and are factory size.
Thanks! Mike

 

[Farmall450]

Nice. My dad has the same one; his runs 2 belts and any vbelt should be easily found at Napa, farm & fleet etc

 

[Mopar_Mikey]

Hey all...Got the compressor all tuned up and seems to be working good now. I replaced the belt, changed the oil, got a new pressure switch (one on it was a 125PSI), new relief valve (one on it was a 115PSI), painted the tank (I need to practice my BC/CC painting so good practice for me), put on a couple Solberg filter/silencer, and now working on a replacement for the tank drain. I am also pondering if I need a magnetic switch. The pressure switch I got is a good quality Hubbell that supports 24 FLA and the motor I have is rated at 22 amps. From the factory this compressor came with just the plug right to the pressure switch. I mainly will be using this casually. Any recommendations out there?
I also am looking for a gauge on how this compressor pump is doing. It is an 80 gallon tank and takes 12 minutes 2 seconds to go from empty to 175 PSI. Is that about par for what a lower end compressor like this is supposed to take to fill? I have seen some guys talking about how their compressors fill in 5 minutes or less...

 

[NedNorton]

This may help explain a few things and give you some places to start diagnosing.

Here is the formula that I have used to calc CFM in the past. I pulled it off the net a few years ago but it seems to be close. I've checked some newer 2 stage compressors and they come out +/- .5 PSI to the ratings. No warranties expressed or implied but it is a good place to start. If there is an engineer that can post a better one, please do. Knowledge is King.

(Tank Volume in Gallons X 7.48) X ((End PSI-Start PSI)/14.7)
----------------------------------------------------------------------
(Time to fill in min X 60)

Here is the math based on the numbers that you gave.

(80 X 7.48) X ((175-0)/14.7)
----------------------------------
12.2 X 60


598.40 X 11.90
------------------
732.00


7123.81
---------- = 9.73 cfm@ 175psi
732.00


I would say that this seems low for a 5hp 2-stage compressor. Most are putting out something in the neighborhood of 17 CFM @ 175 PSI. This may explain why the fill time is in the 12 min range.

If it were me, I would do the math on what RPM the pump is running at and take it from there. You said that you had some fitment issues with the belt. It may be that one of the pulleys was changed somewhere along the way and the pump is now running slower than it originally did. Once you find the current RPM you may be able to increase it and in doing so increase the airflow. You can also check the running amps of the motor and see how hard it is working. Again, if the pump has been slowed down, the motor will be running far under its rated number.

Also, with old compressors (I just rehabbed one) I prefer to run the cut off at 150psi +/- based on some advice a Quincy Tech gave me when I called on my project. His advice was the last few psi before cut-off is what the older pumps have a hard time building due to warn internals and that it is much less strain on the systems to lower the ceiling. So you may want to dial down the presure switch a bit so the pump doesn't have to work so hard. Again, YMMV.

I apologize for the essay long response but I have a soft spot for old tools being brought back to life and put into service.


Very cool project. Good luck!


Cheers,
Chris

 

[Mopar_Mikey]

This may help explain a few things and give you some places to start diagnosing.

Here is the formula that I have used to calc CFM in the past. I pulled it off the net a few years ago but it seems to be close. I've checked some newer 2 stage compressors and they come out +/- .5 PSI to the ratings. No warranties expressed or implied but it is a good place to start. If there is an engineer that can post a better one, please do. Knowledge is King.

(Tank Volume in Gallons X 7.48) X ((End PSI-Start PSI)/14.7)
----------------------------------------------------------------------
(Time to fill in min X 60)

Here is the math based on the numbers that you gave.

(80 X 7.48) X ((175-0)/14.7)
----------------------------------
12.2 X 60


598.40 X 11.90
------------------
732.00


7123.81
---------- = 9.73 cfm@ 175psi
732.00


I would say that this seems low for a 5hp 2-stage compressor. Most are putting out something in the neighborhood of 17 CFM @ 175 PSI. This may explain why the fill time is in the 12 min range.

If it were me, I would do the math on what RPM the pump is running at and take it from there. You said that you had some fitment issues with the belt. It may be that one of the pulleys was changed somewhere along the way and the pump is now running slower than it originally did. Once you find the current RPM you may be able to increase it and in doing so increase the airflow. You can also check the running amps of the motor and see how hard it is working. Again, if the pump has been slowed down, the motor will be running far under its rated number.

Also, with old compressors (I just rehabbed one) I prefer to run the cut off at 150psi +/- based on some advice a Quincy Tech gave me when I called on my project. His advice was the last few psi before cut-off is what the older pumps have a hard time building due to warn internals and that it is much less strain on the systems to lower the ceiling. So you may want to dial down the presure switch a bit so the pump doesn't have to work so hard. Again, YMMV.

I apologize for the essay long response but I have a soft spot for old tools being brought back to life and put into service.


Very cool project. Good luck!


Cheers,
Chris

I am still trying to understand the calculations on the compressors. Thanks for doing that calculation for me it helps. The one I have is only rated at 11.9CFP@100 PSI so I think the calculation you did was pretty much right on. I build up to 130PSI in about 8 minutes. I think setting it at 150PSI is probably a good point for me as well. It seems to be working pretty well. Currently it is set at 175PSI max and kicks back on at 145PSI. If I set it to 150PSI max I think it will kick back in at about 125PSI which should work just fine for me. I'll have to measure the pullies again but I think they are the factory size. The motor is a factory motor that is advertised as a 6.5HP but with a 22 amp draw that does not seem right...it would appear to be a 5HP motor. I'm not too concerned about it as it seems to be working good and will serve my purposes well. Hell, I only have time and about $250 and a little invested in it so far so I'm content. Oh, and I'm at 6000 feet above sea level....does that make a difference?

 

[NedNorton]

Oh, and I'm at 6000 feet above sea level....does that make a difference?

It does make a difference. I know for HVAC sizing we have to derate due to altitude and I imagine that the logic holds for singe and 2-stage air compressors. I don't know all the numbers but the lower density of our air here at altitude makes the pump work harder to achieve the same results that folks see at sea level. You are at 6K and we are at 8.5K.

22 amps is defiantly 5hp. My guess is that it was produced during the "Peak HP" era and that explains the 6.5hp number.

$250 all in is pretty hard to beat! Again, cool project.

Cheers,
Chris

 

[bastage]

Man how do you have the filters on there.. I have the same pump on my compressor & would love to quiet it down a bit.

 

[slackdaddy1]

Great price and great find.
11.9CFM at 100PSI is kinda low for 6.5HP,, still a GREAT compressor for 200.00.

Nick

 

[Heel2toe]

From the pictures it appears as though that is a single stage compressor vs a two stage which could explain the CFM which you are seeing.

I also see you mention you are at 6000' so that could be part of your challenge. There just isnt as much air up there so it takes more work to compress it.

 

[bastage]

Great price and great find.
11.9CFM at 100PSI is kinda low for 6.5HP,, still a GREAT compressor for 200.00.

Nick

That's not a 6.5hp Well at least not a true 6.5.. I have Nearly the same thing except my motor is a 24 amp instead of 22 & its sold as a 6hp. I dont think that makes much of a difference there though.

From the pictures it appears as though that is a single stage compressor vs a two stage which could explain the CFM which you are seeing.

I also see you mention you are at 6000' so that could be part of your challenge. There just isnt as much air up there so it takes more work to compress it.

That is most certainly a 2 stage compressor. Its an ABP-4900 with 2 inline cylinders. The smaller 2nd cylinder which is the high pressure stage is in the back. Below is a picture of mine which is the same pump & nearly the same motor.

 

[Mopar_Mikey]

Man how do you have the filters on there.. I have the same pump on my compressor & would love to quiet it down a bit.

The filter that was on the compressor was cracked and dirty. Could not find a replacement so saw a couple guys up here putting these Solberg filter/Silencers on. Made a plate or some 1/4" x 1 1/2" flat aluminum I had laying around. Tapped 2 1/2" pipe threads into it....of course laid it out kinda...not a rocket scientist here...lol Used a 1/2" ******, street elbow and a 90. Aligned it drilled it and used the factory mounting screws. The pipe thread extended through the 1/4" flat stock so I had to double it up. Here are some pictures of the filters installed. Pretty crude but gets the job done.

 

[Heel2toe]

That is most certainly a 2 stage compressor. Its an ABP-4900 with 2 inline cylinders. The smaller 2nd cylinder which is the high pressure stage is in the back. Below is a picture of mine which is the same pump & nearly the same motor.

I see it now your 2nd photo shows it perfectly, my bad

 

[Mopar_Mikey]

That's not a 6.5hp Well at least not a true 6.5.. I have Nearly the same thing except my motor is a 24 amp instead of 22 & its sold as a 6hp. I dont think that makes much of a difference there though.



That is most certainly a 2 stage compressor. Its an ABP-4900 with 2 inline cylinders. The smaller 2nd cylinder which is the high pressure stage is in the back. Below is a picture of mine which is the same pump & nearly the same motor.

Yeah, it is a two stage B4900 and sometimes is labeled as a TS29 pump. I think it is an Italian company that makes them. I've seen the same pump on DeVilbiss, BelAire, Porter Cable, HF, and ABAC (or at least identical looking pumps) I'll hang with this until it breaks, It will serve it's purpose.

 

[Citation]

I think your 6000 ft value explains your fill time. My back of the envelope calculation suggests at 14.7 psi and an average 12 CFM (ie 12 CFM at all pressures) it takes 10:37 seconds to fill the tank to 175psi. When you cut ambient pressure down to 11.8 psi (pressure at 6000 ft) that number increases to 13:14. So I would say everything is working just fine.

 

[bastage]

The filter that was on the compressor was cracked and dirty. Could not find a replacement so saw a couple guys up here putting these Solberg filter/Silencers on. Made a plate or some 1/4" x 1 1/2" flat aluminum I had laying around. Tapped 2 1/2" pipe threads into it....of course laid it out kinda...not a rocket scientist here...lol Used a 1/2" ******, street elbow and a 90. Aligned it drilled it and used the factory mounting screws. The pipe thread extended through the 1/4" flat stock so I had to double it up. Here are some pictures of the filters installed. Pretty crude but gets the job done.

Better job then I can do at home.. I may go buy a cheap tap & die set just to do this. I keep looking for something to fit this awkward rectangle opening, but hadn't seen anything yet. Thanks a ton for the close up pictures.

Yeah, it is a two stage B4900 and sometimes is labeled as a TS29 pump. I think it is an Italian company that makes them. I've seen the same pump on DeVilbiss, BelAire, Porter Cable, HF, and ABAC (or at least identical looking pumps) I'll hang with this until it breaks, It will serve it's purpose.

Yeah I know you knew what it was. I was posting that to the person who questioned weather it was a 2 stage pump. And mine is an "American Air" branded compressor made by DeVilbiss. To add to your list Coleman & I believe IR used this pump as well.. Its all over the place.

 

[Mopar_Mikey]

I think your 6000 ft value explains your fill time. My back of the envelope calculation suggests at 14.7 psi and an average 12 CFM (ie 12 CFM at all pressures) it takes 10:37 seconds to fill the tank to 175psi. When you cut ambient pressure down to 11.8 psi (pressure at 6000 ft) that number increases to 13:14. So I would say everything is working just fine.

Well thanks for doing the hard work on that for me! It seems fine but just seeing what the guys with more knowledge think. I do know it will be better than my old Craftsman 25 Gallon 4HP. Everything has issues with altitude...baking bread, carburetors, cylinder compression, furnaces, boiling water, snow melting, golf ball drives, and 14.7 air/fuel ratio. Thanks again for the info!

 

[Mopar_Mikey]

Better job then I can do at home.. I may go buy a cheap tap & die set just to do this. I keep looking for something to fit this awkward rectangle opening, but hadn't seen anything yet. Thanks a ton for the close up pictures.



Yeah I know you knew what it was. I was posting that to the person who questioned weather it was a 2 stage pump. And mine is an "American Air" branded compressor made by DeVilbiss. To add to your list Coleman & I believe IR used this pump as well.. Its all over the place.

Hey...after I built my two filter kit I found this...this may be plug and play but
not 100% sure. This is a 1 filter adapter that looks like it's a bolt on. http://www.solbergmfg.com/ViewSeriesDetail.aspx?SeriesId=61&PartNumber=AD-IMC6/10

 

[bastage]

Hey...after I built my two filter kit I found this...this may be plug and play but
not 100% sure. This is a 1 filter adapter that looks like it's a bolt on. http://www.solbergmfg.com/ViewSeriesDetail.aspx?SeriesId=61&PartNumber=AD-IMC6/10

Damn.. I can only find it one place for a reasonable price (6 bucks) and they want another 15 to ship it. I wish I knew that it was for sure the right thing to use. I will email Solberg to see though.. Thanks for the heads up.

 

[Mopar_Mikey]

Damn.. I can only find it one place for a reasonable price (6 bucks) and they want another 15 to ship it. I wish I knew that it was for sure the right thing to use. I will email Solberg to see though.. Thanks for the heads up.

Yeah...shipping *****. Can not find one on Ebay or free shipping at all either. I saw that the pipe thread taps at HF were on sale for cheap. The aluminum I used was a mounting bar that was scrap from work. I think HD and Lowes sells flat stock 1" x 1/4 or 1/2. It's not real difficult and mine was pretty crude using two filters. Using just 1 filter would be real easy. May even be able to use a plastic plate and sprinkler line fittings.
Here is a thread about this very subject on here. http://www.garagejournal.com/forum/showthread.php?t=302324
The best I found was if you get the filter and the adapter all together it's about $30 shipped. http://www.kinequip.com Filter I used was FS-06-050 and the adapter plate is AD-IMC6/10.
They sell replacement parts at https://mastertoolrepair.com under the TS29S pump part #1400477 and a filter as well #FS-10-052 (not sure what is different with the FS-06-050)

 

[bastage]

Yeah...shipping *****. Can not find one on Ebay or free shipping at all either. I saw that the pipe thread taps at HF were on sale for cheap. The aluminum I used was a mounting bar that was scrap from work. I think HD and Lowes sells flat stock 1" x 1/4 or 1/2. It's not real difficult and mine was pretty crude using two filters. Using just 1 filter would be real easy. May even be able to use a plastic plate and sprinkler line fittings.
Here is a thread about this very subject on here. http://www.garagejournal.com/forum/showthread.php?t=302324
The best I found was if you get the filter and the adapter all together it's about $30 shipped. http://www.kinequip.com Filter I used was FS-06-050 and the adapter plate is AD-IMC6/10.
They sell replacement parts at https://mastertoolrepair.com under the TS29S pump part #1400477 and a filter as well #FS-10-052 (not sure what is different with the FS-06-050)

I actually emailed Solberg & got a responce about AD-IMC6/10.. They are going to get me an actual drawing, but this is what was sent.



Doesnt look to be the right size & there is no details listed about the one at mastertoolrepair, but I will email them as well.. Also if I am going to go with a single filter I think FS-14-050 is the one I would get. Still 1/2" threads, but otherwise way oversized, plus its only 16 bucks at kinequip so it actually comes out a little less then others. If I have to come up with a way of making a plate I will put on 2 smaller ones just to slow down the air in the 1/2 port & hopefully quiet it down a bit.

 

[Mopar_Mikey]

I actually emailed Solberg & got a responce about AD-IMC6/10.. They are going to get me an actual drawing, but this is what was sent.



Doesnt look to be the right size & there is no details listed about the one at mastertoolrepair, but I will email them as well.. Also if I am going to go with a single filter I think FS-14-050 is the one I would get. Still 1/2" threads, but otherwise way oversized, plus its only 16 bucks at kinequip so it actually comes out a little less then others. If I have to come up with a way of making a plate I will put on 2 smaller ones just to slow down the air in the 1/2 port & hopefully quiet it down a bit.

Did a quick measurement on my compressor and that does look about right.

 

[md21722]

Your pump up time is within manufacturer specification taking altitude into account.

If you wanted to go crazy with altitude calculations you could call and find out if the pump psi needs to be downrated for the altitude. Some pumps need to be, but it probably won't be an issue since you're not a factory. For example, a 175 PSI max pump may need to be downrated to 150. Similar to the HVAC considerations NedNorton was referring to you, our air's ability to displace heat is reduced which is part of the equation.

For a magnetic starter, these work out OK for the price:

http://www.ebay.com/p/Square-D-Magnetic-Starter-5hp-Single-Phase-208-240-Volt/1654234706

 

[bastage]

I got the actual drawing from Solberg today.. Did a quick measurement & it looks like it'll fit fine.




Edit: I went ahead & ordered the adapter & the FS-14-050 6" filter. I hate paying 15 bucks for ground shipping on what will be maybe a pound, but I guess it is what it is..