The two-stage air compressor I built 15 years ago has been cycling too
often of late. There's a leak somewhere.

I didn't make the pump, just assembled stuff to fit in the space I
had. I found the two-stage pump on the bargain table at Northern
Tool. Turned out it had a broken ring but the cylinder wasn't
scored. I repaired it and have used it for at least 15 years since.

Fixing the present problem, the leak, wasn't nearly the fight I was
afraid it might be. God bless teflon-loaded pipe dope -- and me for
having sense enough to use it 15 years ago when I built this kludge.

I discovered that the safety valve was leaking a little so I replaced
that. Didn't make much difference. I noted that the pressure
switch I'd used was rated for 125 PSI on, lower off. Oh, golly, I
must have been in a hurry or feelin' poor at the time. I'd just
torqued the screws so it'd run between about 175 and somewhat less.

I picked up a new (properly rated) pressure switch and checkvalve
today at Grainger. I thought the old checkvalve might be a bitch
to get out but it wasn't bad at all. I thought I might have to do
much more diassembly than I did to get the pressure switch off, but
there was just enough clearance so it could unscrew without
dismantling a bunch of other plumbing. I claim no foresight in the
design; a look at it would certainly remove any doubt about that.
Luck is good. Careful design is good, but it's hard to beat good
luck. I didn't really design this kludge, just built it. I didn't
have time to design stuff then. I wanted more air ASAP for doing
rustwork on cars. Had a herd of kids to educate so available funds
went to tuition rather than to Detroit or Japan while I wrenched and
did bodywork to keep the transportation fleet running and presentable.
Bodywork needs lots of air.

OK, new checkvalve, new safety valve, new pressure switch, everything
plumbed and wired. I crimped ring terminals onto the stranded power
cord while I was in there. They were just under screws in the old
pressure switch. Maybe I didn't have any crimp terminals handy when I
built it.

I presently have a plug where the highside pressure gage goes; the
old gage is in the trashcan. I'll pick up a new one tomorrow.
Fired it up. Yes, with no gage. What the hell, it's running with a
brand new pressure switch and a brand-new ASME-rated safety valve,
right? I still didn't get near it until it cycled off. The old
gage was too shot to trust anyway.

It kicked on again in about five minutes. DAMN! Might I have a pin
hole or crack in the small tank? That would be very bad news. It
would mean rebuilding the whole system. I could do that, but it
sure wouldn't be on the top of my list of fun things to do in my
dotage. Gloom! Doom on me. The tank is galvanized inside and
out, shouldn't have failed me even though it was a free scrounge 15
years ago. Oh **** oh dear and dammitall, I purely hate when ****
happens.

With some pessimism I sniffed around the only other place that there
is pressure. Well, dang me and hang me, I could feel (and even hear,
I think) a leak where the water catchbowl in the filter-regulator
screws in. If I can hear it at all , it's a non-trivial leak.
Hearing impairment is quite common in vets of my vintage. The 50 cal
machinegun makes a lot of noise and sojers didn't wear earmuffs for
obvious reasons.

I could definitely feel the leak even with a dry finger. Don' need
no soap bubbles to confirm that one. My reaction was only
comprehensible in context: "OH BOY, HOT DAMN, A LEAK, YAYYYY!"

Dumped the tank yet again, unscrewed the bowl. O-ring looked tits.
I don't know how that bowl could vibrate loose under pressure, but it
does seem to have done that. I cleaned the O-ring and mating
surfaces, smeared some silicone grease on it, screwed it back in and
tightened it with a strap wrench.

I'm glad I renewed the safety valve and checkvalve even though I now
know the primary leak was at the regulator filter unit. The old
safety valve was definitely leaking a little and the old checkvalve
looked a little crusty as well upon autopsy. I don't know if it was
leaking or not, but if it wasn't it would have before much longer.

I was about to note that this may be the first repair I've done in
recent memory that didn't involve some machining or welding but just
wrenching. That's almost true -- but I did cut 1/8" off the riser
tube and re-flare it. I did the cut with the bandsaw because a tubing
cutter wouldn't get anywhere near close enough. Deburred the cut,
cleaned out the copper dust, reflared it. That minor trim made it fit
much better; it went back in with no fight at all. I replaced the
belt-and-pulley guard made of a shadowbox welded from 1/8" x 3" HRS
and shrouded by a rack from an old refrigerator. I'd rather it not
eat my knee when it decides to run. It is kneeside because I
correspond with a laptop 'puter sitting on a piece of plywood on an
open tool drawer at my workbench.

I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

On Fri, 07 Jan 2005 02:26:29 -0600, Don Foreman
wrote:


I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

Well done!

My very old DeVilbiss single stage double piston compressor is
starting to clank ever so softly...looks like Ive got some compressor
work to do in the near future also.

gunner

"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio

Get a Quincy and let you're grandchildren rebuild it when they get old.


"Gunner" wrote in message
...
On Fri, 07 Jan 2005 02:26:29 -0600, Don Foreman
wrote:


I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

Well done!

My very old DeVilbiss single stage double piston compressor is
starting to clank ever so softly...looks like Ive got some compressor
work to do in the near future also.

gunner

"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio

On Fri, 07 Jan 2005 17:23:35 GMT, "Tom Gardner"
wrote:

Get a Quincy and let you're grandchildren rebuild it when they get old.

Got a new free one? This one was manufactured in 1957.

Gunner



"Gunner" wrote in message
.. .
On Fri, 07 Jan 2005 02:26:29 -0600, Don Foreman
wrote:


I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

Well done!

My very old DeVilbiss single stage double piston compressor is
starting to clank ever so softly...looks like Ive got some compressor
work to do in the near future also.

gunner

"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio


"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio

Call 'em, it's still under warranty.


"Gunner" wrote in message
...
On Fri, 07 Jan 2005 17:23:35 GMT, "Tom Gardner"
wrote:

Get a Quincy and let you're grandchildren rebuild it when they get old.

Got a new free one? This one was manufactured in 1957.

Gunner



"Gunner" wrote in message
. ..
On Fri, 07 Jan 2005 02:26:29 -0600, Don Foreman
wrote:


I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

Well done!

My very old DeVilbiss single stage double piston compressor is
starting to clank ever so softly...looks like Ive got some compressor
work to do in the near future also.

gunner

"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio


"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio

On Mon, 10 Jan 2005 20:27:33 GMT, "Tom Gardner"
wrote:

Call 'em, it's still under warranty.


Ya think? Ill call tomorrow.

Gunner


"Gunner" wrote in message
.. .
On Fri, 07 Jan 2005 17:23:35 GMT, "Tom Gardner"
wrote:

Get a Quincy and let you're grandchildren rebuild it when they get old.

Got a new free one? This one was manufactured in 1957.

Gunner



"Gunner" wrote in message
...
On Fri, 07 Jan 2005 02:26:29 -0600, Don Foreman
wrote:


I fired up the refurbished air compressor. It's now at three
hours and holding without cycling. I'm declaring victory.

Well done!

My very old DeVilbiss single stage double piston compressor is
starting to clank ever so softly...looks like Ive got some compressor
work to do in the near future also.

gunner

"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio


"Gunner, you are the same ridiculous liberal f--k you ever where."
Scipio



"At the core of liberalism is the spoiled child -
miserable, as all spoiled children are, unsatisfied,
demanding, ill-disciplined, despotic and useless.
Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke