F100: On Board Air Compressor
By Steve Delanty
Anyone who owns a shop air compressor knows what a convenience it
is. Filling tires, running air tools, cleaning and drying parts,
compressor is almost a must for any serious gearhead !
whadda Ya do when You want compressed air out on the road?
You just plug Your air hose into one of the air fitting that’s dangling
Your front or rear bumper of course!
I decided I wanted an on-board air compressor for my ’71 F100
built a cheap and simple system from an old air conditioning compressor.
how I did mine:
thing was to aquire an old air conditioning compressor.
of the most desirable types of compressors to use for on board air
the old York compressors, which were used on zillions of old Ford
other) vehicles in the 60’s, 70’s and 80’s. These compressors are an
2 cylinder design with a built in oil sump. The oil sump is inportant,
some compressors have no sump but rather circulate lubricant oil
with the refrigerant to keep the pump lubricated. The only way to
a "sumpless" compressor in an on-board air setup is to use a
on the compressor inlet which is not a very desirable way to go.
of the York type compressors have an oil sump to contain the
oil, so they need no external oiler to keep them healthy.
York pumps have a model # tag bolted to the cylinder head, and
have a number something like this: F2
center group: "10R"
is the important group to look for.
may find 3 models of this compressor which all look similar:
"8R", and "10R".
The "10R" is
the most desirable since the larger
have longer strokes and so move more air.
You find an "L"
instead of an "R"
after the number, don’t worry it means
the air outlet is on the left side of the pump instead of the right side…
I had the pump in hand, the next thing was to find a mounting
and crankshaft pulley for the pump. That was easy, since the
A/C pump was used as stock equipment on almost all the
A/C equipped Ford cars and trucks.
found an A/C equipped, FE390 powered truck at the wreckers and
the mounting bracket and 3-groove crank pulley from it.
bolted right up to my motor in a matter of minutes…
a photo of it installed:
used as an A/C pump, the compressors are lubricated by a mineral oil
lubricant. There is no conveniant way to check / fill / change the oil
onmost of the York pumps without removing the sump pan.
Your pump is full of oil when You get it, and You only intend to use the
occasionally, the mineral oil lube will probably be fine for years.
intend to use my pump a lot, so I modified mine a little…
removed the sump plate and head and thoroughly drained and cleaned all
mineral oil based lube out of mine. Then I drilled and tapped a hole for
1/8" pipe plug as close to the bottom of the compressor sump as
That’s my drain plug… Then I drilled and tapped a hole a
up the crankcase, about where the oil level should be when full.
my oil level check hole. I also drilled and tapped a hole near the
the crankcase and screwed a pipe elbow into it so the elbow points up.
I screwed a 1/8"" to 1/4" adapter onto the elbow and screwed a short
of 1/4" pipe into it with a pipe cap on the top. The cap has a 1/8" hole
in it. The 1/4′ upright pipe has a wad of fine mesh stainless steel
stuffed into it to catch oil. This little assembly forms an external
vent, which reduces the amount of oil carried thru the pump and
into the compressed air, since in stock form the pump vents the
to the pump air inlet…
i was done the pump looked like this:
the pump was drained and mofified, I refilled it with a straight 20W
oil. I feel better knowing I can check and add oil to my pump
in a while…
the pump was set up and mounted, I needed an inlet air filter.
made a filter assembly from a plastic electrical box, a chunk of air filter
rubber, and some screen. It’s not the most elegant setup,
it’s what I had laying around in the garage…
outlet air from the pump is plumbed into a manifold that splits off to
pressure switch, a pressure relief valve, an air pressure gauge, and two
lines, one that goes to a quick disconnect under the front bumper and
that goes to the rear of the truck. The one to the rear splits under the
and one hose goes to a portable air tank in the bed, and one goes to
quick disconnect under the rear bumper.
MUST use a pressure relief valve!! The York
can easily produce pressures well in excess of 200 PSI, and
burst Your air tank! The pressure relief valve should be rated for a
equal to or lower than the rating of Your air tank.
is rated at 150PSI.
air tank that explodes can send You or someone else to the hospital
the morgue, so please be carefull, O.K.?
the air plumbing was done, the last bit was to hook up the wiring.
comes from the igntition switch, so the pump clutch can only be
when the key is on. Power then goes to 10 amp fuse, an
on/off" switch on the dash, then to the pressure switch, then to the
the engine is running and the power switch is on, the compressor will
the tank to about 115PSI then shut off. It comes back on when pressure
below about 105PSI.
managed to scavange used/surplus parts for almost all of my system and
up with a $$ investment of under $70. I use it to run air tools,
pressures, fill air matresses and inner tubes at the lake, and much more!
that I’ve got on board air, I dunno how I ever did without it!