Results 1 to 12 of 12

Thread: New (to me) Compressor - Water & Auto Drains

Discuss general restoration and car care topics (paint & body, upholstery, woodworking, etc) as well as tools.

  1. #1
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    New (to me) Compressor - Water & Auto Drains

    I moved my old compressor last week. Its Harbor Freight auto drain had plugged leaving a couple of cups of water inside. Along with the water were a LOT of decent size chunks of rust. As the tank is 40+ years old I decided it was time to retire it. New tanks cost about 1/2 to 2/3 the cost of a new compressor. New cast iron pump compressors with the CFM I want are north of $500 so I found and purchased a good used one locally.

    The "new" compressor looks showroom new and clearly hasn't been used much. However, I heard water inside and decided to carry out maintenance before using it. I opened the drain **** and all it did was slowly drip. I dropped the tank pressure to about 10 PSI and slowly unscrewed the petcock. Even with the petcock removed all the tank did was drip. I grew impatient and probed the port with a bent coat hanger. Then all heck broke loose. I disloged whatever had plugged the port and about a quart of muddy water geysered out against the floor splattering me and most everything close in the garage. That will teach me to be impatient. I should have at least taken the thing out to the driveway. Now that I have cleaned the tank, the garage floor, and me up, it is time to move on to different plumbing and a better auto drain.

    I want a better auto drain than the Harbor Freight one... one less likely to plug (which is what I found wrong with the HF one). The electric timer based ones don't make sense for a home shop (adjustable drain time 1-10 seconds every 1 to 45 minutes). They can also be expensive (Chinese from about $25 to name brand U.S. for upwards of $160).

    Now that you know the background it's time to finally ask my question.

    I am considering buying a programmable timer and solenoid valve to make my own more flexible auto drain. Before I start that project, do any of you use auto drains and if you do, are you pleased, how is yours adjusted, and how much did you pay for it?
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  2. #2
    Great Pumpkin JPSmit's Avatar
    Join Date
    Nov 2004
    Location
    Toronto, ON
    Posts
    17,720
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    23
    Thanked in
    21 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    I feel like the "clearly hasn't been used much" might be the key - I am just in the habit of draining mine every time or two and have never had an accumulation problem. Can't really add to the solenoid timer bit except to say that my solution is free and works just fine.
    John-Peter Smit
    1976 MG Midget
    1969 Vauxhall Viva GT
    1958 Fiat Multipla (Barn art)

  3. #3
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    For the time being I have made up an 18" long, 3/8" diameter drain hose. It has an elbow fitting that screws into the bottom of the tank and a ball valve on the other end. That will make it easier to access and less likely to plug than the petcock. I'll use that until I decide to buy or make an auto drain.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  4. #4
    Great Pumpkin JPSmit's Avatar
    Join Date
    Nov 2004
    Location
    Toronto, ON
    Posts
    17,720
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    23
    Thanked in
    21 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    Quote Originally Posted by dklawson View Post
    For the time being I have made up an 18" long, 3/8" diameter drain hose. It has an elbow fitting that screws into the bottom of the tank and a ball valve on the other end. That will make it easier to access and less likely to plug than the petcock. I'll use that until I decide to buy or make an auto drain.
    I suspect that might be all you need. will the hose take 100+ lbs of pressure?
    John-Peter Smit
    1976 MG Midget
    1969 Vauxhall Viva GT
    1958 Fiat Multipla (Barn art)

  5. #5
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    Yep. The hose I have can take 100 PSI.

    However, I have also ordered a 2 foot piece of 6AN braided hose. I will install that in my homemade drain hose once it arrives. The braided hose is listed for something close to 1000 PSI.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  6. #6
    Great Pumpkin TR3driver's Avatar
    Join Date
    Aug 2003
    Location
    Sunny So California
    Posts
    18,564
    Thanks Thanks Given 
    3
    Thanks Thanks Received 
    37
    Thanked in
    35 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    I picked up a used IR automatic drain (the kind triggered by the compressor cycling) on flea-bay for not much more than the HF one. But never have gotten around to plumbing it up; the manual ball valve works well enough. I brought the tank drain out with galvanized pipe and put the ball valve where I can open and close it with my toe. The pipe also provides a sump of sorts, so the first cupful or so of accumulated water sits in it rather than in the tank. If rust becomes an issue, it's a lot cheaper to replace than the tank. And absolute worst case, if it does corrode enough to burst (my compressor runs to about 180 psi), it's a lot less dangerous than the main tank, too.

    The strange part is that this compressor setup (80 gallon vertical tank, mounted outdoors) seems to generate a lot less water than my old 20 gallon horizontal did sitting under the bench in the garage. I really have no explanation for that, unless somehow the water is accumulating in the crossover tube between compressor cylinders (new setup is 2 stage, old setup was 2 cylinder single stage) and getting blown out when the switch cycles.
    Randall
    56 TR3 TS13571L once and future daily driver
    71 Stag LE1473L waiting engine rebuild
    71-72-73 Stag LE2013LBW waiting OD gearbox rebuild

  7. #7
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    Interesting. I considered getting a new vertical to replace the 20 gallon horizontal I had for the past 25 years. However, I really don't have a good place to put that in the garage. Also, the verticals in my budget seemed to have diaphragm pumps. After my last compressor I really want to stay with a cast iron piston unit.

    Last night I purchased a used, ASCO (brand) high-pressure valve off eBay. I will eventually pair that with a digital timer from HF. As purchased the HF timer only provides on/off cycles in minutes, not seconds. I have used this timer before on a pet feeder. There are two solder pads inside that can be bridged to change the output timebase to seconds. My plan is to pair the modified timer with the ASCO valve for a homemade auto drain. I will set it to dump for 4 or 5 seconds sometime in the middle of the night.

    Eventually I will make my own auto-drain with those two components. However, I will continue to use the manual hose and ball valve until I get around to the auto drain project.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  8. #8
    Luke Skywalker LarryK's Avatar
    Join Date
    Mar 2007
    Location
    Millstadt, IL
    Posts
    1,606
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    3
    Thanked in
    3 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    I bought an Industrial Air upright 60 gal, 2.7hp from Rural King for $399. Cheaper by $40 from Ward Tools and cheaper than Harbor Freight. Got the extended warranty and found a service center that comes to the shop for repairs and warranty. Had it for 3 months, very happy with it. I had a Craftsman 30 Gal 5 hp horizontal for 25 yrs that developed a pinhole in tank, replacement for approx. same ( as they aren't made anymore or no parts) would have been $369+.
    Larry K
    58 Jag 3.4 MK 1 auto under restoration, 57 Jag 3.4 MK1 manual ,
    03 Cooper S, 2011 Cooper S Countryman, 2011 Land Rover LR4 HSE LUX, 1964 Valiant V200
    Also had , 68 Cortina 1600E, 64 Spit 4 & 80 1500, 73 GT6 3, 71 XJ6, 79 XJ6, 86 XJS V-12, 53 XK120 OTS.

  9. #9
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    Your pinhole experience is similar to what I experienced with my old compressor. Both my old compressor and the one I just bought are 20 gallon horizontals with cast iron, 2 piston pumps (both Campbell-Hausfeld but the older labeled as Sears). I've had to replace the reed valves twice on the old pump but that's not too much to ask every 10 years or so. I feel I did very well with the new compressor in that I only paid $200 for it and it really is like brand new. The current, comparable model sells for about $425 when discounted.

    This week I received the high pressure diaphragm valve and 6AN braided hose I purchased for my DIY auto drain. I'm pairing that with the HF digital timer modified to operate on/off times down to a second. I have manually tested these components and they work well together. After I run the drain line outside the garage I'll run some test cycles before putting it into service. Per advice I received, I have put an additional ball valve inline with the auto drain solenoid valve. That will allow me to shut everything down when I am not going to be around to keep an eye on things.

    The only thing I don't like about the new compressor is that it has a big hysteresis loop with its on/off pressure limits. It's rated as a 135 PSI compressor/tank. It does pump up and stop at about 135. However, when you start using air, it doesn't come back on until about 95 PSI. I'm sure that will be OK but I'm used to my old compressor which pumped up to 150 and came back on when the pressure dropped to about 125.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  10. #10
    Great Pumpkin TR3driver's Avatar
    Join Date
    Aug 2003
    Location
    Sunny So California
    Posts
    18,564
    Thanks Thanks Given 
    3
    Thanks Thanks Received 
    37
    Thanked in
    35 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    Frequently (not always) there is an adjustment for that inside the housing for the pressure valve. Remove the cover and look for a "big" adjustment and a "small" one. The smaller one is usually the pressure differential between start and stop (hysteresis).

    For example (random image from Google), in this case it's the nut on the right.
    Randall
    56 TR3 TS13571L once and future daily driver
    71 Stag LE1473L waiting engine rebuild
    71-72-73 Stag LE2013LBW waiting OD gearbox rebuild

  11. #11
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    I will take a look at the pressure switch assembly again. I was in there hooking up a new cord when I changed the motor over to run on 240V. I probably looked right at the part to tweak and didn't recognize it.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

  12. #12
    Yoda dklawson's Avatar
    Join Date
    Mar 2005
    Location
    Durham, North Carolina, USA
    Posts
    5,877
    Thanks Thanks Given 
    0
    Thanks Thanks Received 
    11
    Thanked in
    11 Posts

    Re: New (to me) Compressor - Water & Auto Drains

    I have spent some time trying to narrow the on/off hysteresis of the compressor. Suffice it to say it did not work as expected. I could change the on/off trip points but they moved together regardless of which spring was adjusted. (Fixed on/off window). Compounding that, the threaded shaft supporting the "left" spring started spinning with its adjusting nut. I gave up and got the settings back close enough to where they were so I could use the compressor.

    I am ordering a different pressure switch with better defined adjustment screws. My hope is that the new pressure switch will let me set the on/off trip points to a more acceptable 110 to 135 PSI range.

    I put together my homemade auto drain with its final components. It works well enough. A brass street elbow screws into the bottom of the tank. Barbed fittings on each end of a 2 foot piece of SS braided hose connect the elbow fitting to an Asco (brand) 120V fluid valve. A modified Harbor Freight digital timer cycles the valve on for 1 second at 2 a.m. daily. That's enough for a big burst of air to remove the moisture from the bottom of the tank. A homemade muffler on the end of the discharge hose keeps the noise down to a VERY acceptable level. Each one second blast drops the tank pressure by about 10 PSI so I added a ball valve to the circuit to disable the auto drain when I am not using the compressor.
    Doug L.
    '64 Morris Mini Cooper-S 1275
    '67 Triumph GT6 Mk1

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •