In order to get a wider audience than the few gluttons for punishment that are following/contributing to Dad's Engine I'm starting this thread to discuss the options for A/C compressor on Dad's truck. And, there will be several posts up front to kick this off, so stand by.

But, to set the stage, the 81's came with the York or Tecumseh compressors, which Bill called "antique" recently. However, in 82 Ford came out with the rotary Sanden FS6 compressor which is smaller, lighter, and takes less power to run. So, the question has arisen regarding the ability to swap the York for an FS6 - hence this thread.

Toward that end I emailed two companies that deal in A/C systems - Vintage Air and Classic Air. And, both responded quickly. Vintage Air doesn't have anything to help but did send me to Dealer Automotive Services to talk to Travis. But Classic Air does have adapters to allow the mounting of a rotary compressor on the York-style brackets. And, both guys said that the rotary compressors are "much more efficient" and are also lighter and smaller.

As it turns out, I have the brackets for an FS6 off of a Windsor, so took some time to check things out today:






Compare that with the York compressor:






So, forgetting for a moment the issues of mounting the rotary compressor, which I'll address in another post, what do you think of the look and fit of the rotary compressor? Is the added efficiency worth it?

 

You asked about looks, I like the look of the older style better, just looks more substantial and capable and the other one looks out of place.

But if the other one requires less power to operate and is just as capable (or even moreso) then I'd probably be inclined to go with it.

But I guess I'd want to know how much better it is, how much less of a drain on the engine it is... in the exquisitely detailed fashion you are known for providing...

This is how we all view you when you do that:

 

At the risk of getting ahead of the critics, here's another option. Curtis from Classic Auto Air called back. They have a neat little bracket that mounts on top of the stock Ford bracket for the York compressor and holds the rotary compressor. And, it also uses the other bracket that mounts the idler pulley, so my plans on the alternator will work as well.

But I asked him why I would want to convert. He laughed and said the York compressor draws 12 HP while running while the rotary pulls less than 3 HP. Further, the York must be run every two weeks or so, even through the winter, or it will leak the "Freon" out. I'd heard that many moons ago but didn't realize it was for a specific type of compressor. However, he says the rotary compressor doesn't have that problem.

So, here's a picture of their conversion on a 428 in a Mustang. I like the way the compressor sits lower than with the Windsor brackets. And, I like that the hoses come off of this compressor on the side instead of the top like in the picture of the rotary in the previous post. With this approach the hoses will be low and go below the air cleaner snorkel. With the other one the hoses will be high and have to be above the snorkel.

 

To the student in the third row throwing spit *****, did I answer the question.

 

The Sanden also weighs significantly less than the York.

 

Now, let's talk a bit about what it would take to put the standard Ford rotary compressor on an M/400. It really isn't all that difficult, but does require some fabrication. The main bracket bolts perfectly to the water pump, but it is the rear bracket that doesn't line up with the holes in the head.

This picture shows the issue:

• Yellow: These arrows point to the rear bracket, which is supposed to bolt to the head at the bottom and to the back of the ears on the compressor. But, it won't go behind and is bolted instead to the front of the ears.
• Red: This arrow shows a gap between the back of the PS pump bracket and the head, which is where the stock M/400 bracket should be. Obviously this needs to be filled.
• Orange: This arrow points to a bolt that neatly lines up between a previously unused hole in the bracket and a tapped hole in the head. But, it needs the spacer - that I seem to have lost. However, that can be easily found or made.
• Green: This hole is where the bolt pointed to by the orange arrow usually goes.
• Blue: This bolt, which is the pivot bolt for the later style PS bracket, needs to screw into the rear bracket.

So, what would it take? Beyond the one bolt hole that the pivot bolt goes into, there are three more bolt holes in the head. So a plate could easily be made to bolt up to those holes. And then nuts could be welded to the plate to accept the two bolts from the rear bracket. That plus a couple of spacers and it would bolt right up. Plus, the later style PS pump bracket will then fit nicely.

 

Newer compressor uses 25% of the power required by the old one, that's a pretty compelling reason.

 

Yep. I'm thinking that Classic Auto Air is the way to go. They have the brackets, compressor, receiver/dryer, and hoses. But the hoses come extra long with only one of the fittings crimped on. You mock it up, cut the hose, and then have someone locally crimp the other end on. Or, ship it back to them and they'll crimp it on.

That will let me route the high pressure hose back to the firewall and across like the later trucks did. I've always disliked the way our trucks have the hoses running at a haphazard angle across the middle of the engine bay, so this will let me clean that up.

 

I bought an under hood kit from Classic Auto Air for my Maverick. Routed the AC lines like you're planning. Here's how it installed with their bracket for the Sanden on a 302.



They provided great customer service. When you measure your AC lines and take them to get the fittings crimped, be sure to mark them where then need to be clocked. You probably knew that but just thought I'd mention it.

 

I think it's rotary hands down. It even looks aesthetically pleasing.

Where did you have those W brackets stashed?

 

Mav - That's just how I want to do it. Thanks for that pic. And, for the words regarding customer support - which certainly fits with my experiences today.

Bruno - the W brackets were upstairs, right where you've been looking. Do you need some?

 

No, I thought we were hard pressed to find the ones I gathered up? Maybe that was the exhaust manifolds or the timing cover? Was it the heads and rockers? Could have been the rods and pistons though.

 

Gary, I'm going to let you figure this out while I work on getting the beast running. I'll be tackling the brakes and tires next.

FWIW, I do like the way the Maverick is setup, and it will probably be your best route.

 

Sanden, on the conversion bracket, like I initially suggested.
The york is a tough old beast, but requires a lot more power to drive it, hench the belt flop issue that is common on these older fords.
Even if you made all the mods to use the FS10 on the 400, it won't look as clean as the sanden, and you'll want to buy a new compressor anyways. Plus, the old FS10 isn't as good as the newer sanden.

Classic air has already done the engineering, and it flat out works well. The only drawback to their setup, they don't have a way to use the cutoff valves that older fords (like dad's 74) had at the compressor, which would allow removing the lines from the comp, without losing the refrigerant charge. Still, I plan to go this route on dad's truck. That york still works, but it is 40 years old...........

 

Oh yeah, I meant to add this: The only reason to add a york comp on a nice restoration/restomod rig, is for onboard air to inflate tires or power air tools. The york is unbeatable for use as an air compressor, since they are so tough.

Now, if you were going for a concourse correct restoration, the york would be a requirement, sadly........