Since I'm upgrading to a york, I decided to disect my old A/C pump to see how it worked, and to see how much wear it had.

I've used this pump for onboard air for a good 8 years. After the first couple of years, I pretty much gave up oiling it. It maybe saw 1 or 2 caps of oil a year.

I was amazed to find 3 cylinders. Then I pulled the back cover and found 3 more :eek: :eek: :eek: 6 total! Everything was very well lubed, yet virtually no oil came out the air hose. All the cylinders still had hone marks.

The cylinder bores measure 1 3/8, and the stroke is 1 1/8. I'm not smart enough to compare it to a york, but I think it might be pretty damn close.

So has anyone taken their york apart?

http://home.earthlink.net/~mattsara/bb/ac1.jpg

http://home.earthlink.net/~mattsara/bb/ac2.jpg

http://home.earthlink.net/~mattsara/bb/ac3.jpg

BTW, I never used a filter either

The 10 ci yorks are 2 cylinders, have a bore of 1.875, and a stroke of 1.866. At a glance, it looks like the motorcraft may push more cfms.

http://home.earthlink.net/~mattsara/bb/yorkspecs.jpg

Interesting thread keep it going!

I wonder if you could modify the Motorcraft pump to hold oil in the crankcase.

My Ford shop manual says the FS-6 compressor has 10.4 ci displacement.

Originally posted by Dustball
My Ford shop manual says the FS-6 compressor has 10.4 ci displacement.

Wow that's great! Now I have to decide if I actually want to upgrade.....er downgrade to my york. Maybe I should just run both!

Paul it appears the in the intake actually goes through the "crankcase". It doesn't look like this pump needs any mods though. I can't find any signs of wear.

I've been saying forever........

Yorks are overrated!

Unless they fit stock in your vehicle I see no reason to waste even 50 cents on one.

I've been looking for more info on the FS6 pump, and I keep coming across the term "variable displacement". It seems that all the rotory style pumps are variable displacement. What the heck does that mean?

Yorks ARE overrated. I have used gm/ fridgidaire A6's for years. They outpump yorks like nothing else. Similar design as the one above: 6 pistons, TEFLON rings. And they bolt on chevy motors (is there anything else?)with factory brackets. no lube and no blowby. Teflon ROCKS!!

Is the A6 the old style long ones? Thats what I've been running on mine for a few years (came stock on the truck). It did actually partially sieze up on me this year (first time I tried to use it this year). I put some oil in the intake and it seems to be ok now. Any idea on the displacement of them?

Pete

yorks overrated?? duhhh, why do you think the auto man. changed the style?? the only thing "better" about the york for an air pump is its own oil res. i have a york on my OBA but thats mostly because it was stock and it has the oil res.

I've used this pump for onboard air for a good 8 years. After the first couple of years, I pretty much gave up oiling it. It maybe saw 1 or 2 caps of oil a year.



if you had to guess how many hours do you think you have run the pump?

Originally posted by mrs. camo

if you had to guess how many hours do you think you have run the pump?

Wow, that's a tough one. The first couple years I had it, it seemed I was the only one with air. As you could imagine I was airing up a lot of tires. I also ran without a tank for 3-4 years. I just used a free flowing air chuck.

Most the time I aired my bronco and one other vehicle up. I wheel at least every other weekend. I dunno :confused:

I'm trying to figure a guesstimate, but I keep coming up with ERROR. It's seen a lot of use, that's for sure, pluss the years of service as an actual a/c pump(1984) No signs of wear.


So does anyone know what "variable displacement" is?

Originally posted by Nobody


Wow, that's a tough one. The first couple years I had it, it seemed I was the only one with air. As you could imagine I was airing up a lot of tires. I also ran without a tank for 3-4 years. I just used a free flowing air chuck.

Most the time I aired my bronco and one other vehicle up. I wheel at least every other weekend. I dunno :confused:

I'm trying to figure a guesstimate, but I keep coming up with ERROR. It's seen a lot of use, that's for sure, pluss the years of service as an actual a/c pump(1984) No signs of wear.


So does anyone know what "variable displacement" is?

How did it work yesterday? :)

Originally posted by Nobody

So does anyone know what "variable displacement" is?

C'mon..... it's been 7 months now! anyone?

actually I just happened across this thread and decided give it a bump! :nuke:

Originally posted by Aggro
Yorks ARE overrated. I have used gm/ fridgidaire A6's for years. They outpump yorks like nothing else. Similar design as the one above: 6 pistons, TEFLON rings. And they bolt on chevy motors (is there anything else?)with factory brackets. no lube and no blowby. Teflon ROCKS!!
So what does that pump come on and what shape is it?

Variable displacement compressors were designed to elimintate the cycling of the a/c clutch. There is a waved plate which changes the 'stroke' essentially

Originally posted by 66CJdean

So what does that pump come on and what shape is it?

That pump was on my 2.8L in my 84 bronco II, but I think it was the main pump ford used in that era. This is what it used to look like.... I've got a little bigger engine now :D........... I need too adjust my radiator before I can mount the york. Been a year without air now.....sucks! I actually carry two spares and transfer hose, which is enough to air up at the end of the day. Still can't wait to get on-board air II up and running. I'm going to do a much better job.

http://home.earthlink.net/~mattsara/bb/28in.jpg

Originally posted by JEEPRZ
Variable displacement compressors were designed to elimintate the cycling of the a/c clutch. There is a waved plate which changes the 'stroke' essentially

There is a waved plate, but the a/c system had a hi/low pressure cut out, so the pump cycled like any other.

I still don't really understand what variable displacement means though.