Under Dash AC

[Beemon]

Has anyone tried these units in a 50's era Buick, or know someone who has? We're in the mid 90s here, probably not as bad as other places, but a huge change for us. The reason I ask is because it doesn't look like it would fit under a 56 dash. The under dash kits look to be the simplest route to go. You could run the lines through a plenum drain hole and through the open vent so you wouldn't have to drill a bulkhead connector, or put one out of sight behind the plenum. I don't have the means to buy and ship 56 ac parts since they're rare and costly when they pop up,  but $200 here and there with summits free shipping doesn't sound impossible. 

[NTX5467]

IF you can find  '64 and prior big Ford car with factory a/c, you can use that factory under-dash unit.  Or even from a Mustang as all Ford had for factory a/c was under dash units.  In '65, the Galaxie-type cars finally got "integral" a/c.  Parts for these Ford units should be available, especially for the Mustang models.  They look quite nice, although a Buick emblem could take the place of the Ford crest.  From there, you'll need the mounting brackets, possibly from a mid-60s 401 or 425 Buick?  The A-6 compressor has a similar Denso unit that is a direct replacement for the GM A-6, is made of aluminum, takes less horsepower to run, and is in the $300.00 range (last time I checked).  The system would just need hoses from this point and electricity for the compressor and inside unit.  The thermostat is on the inside unit, so nothing is needed in the way of POA (the real OEM style!!) or pressure switches to cycle the compressor, as far as I know.  You can probably find some Ford schematics online.  Find an auto supply that can supply the needed line fittings and can make the hoses you need (barrier-type hose).  The factory GM hose fitting for the compressor lines has many configurations, depending upon how the hoses need to enter and exit the rear of the compressor.

 

Condenser size if very important with R-134a.  Put the biggest universal one you can find that will also fit in the desired space behind the grille.  "Mass flow" rather than "serpentine flow" is supposed to work best, too.  And, of course, the receiver/dryer has to be plumbed somewhere.

 

I found some wood floor underlayment at Home Depot the other night.  Silver mylar on both sides with a thin layer of foam in the middle.  Use these to make the door watershields behind the trim panels.  Some heat reflectivity and foam for insulation.  Then some DynaMat (or similar) on the floors and possibly some new carpet padding under the existing floor covering.  Something above the head liner, too, if possible.  All for better sound and heat/cold insulation.

 

Don't forget that you'll need to drill a hole in the trans hump for the condensate drain tube!

 

There's you an OEM-based system that can possibly be salvage-yarded with ready (hopefully) parts availability, if needed.

 

Enjoy!

NTX5467 

Edited June 27, 2017 by NTX5467 (see edit history)

[buick5563]

I have installed around a dozen "Old Air Products" underdash units and they cool relatively well.

New and under a grand for most of what you need.

[Beemon]

3 hours ago, buick5563 said:

I have installed around a dozen "Old Air Products" underdash units and they cool relatively well.

New and under a grand for most of what you need.

 

Anything on a 56 Buick? The 54 and 55 dash are about 3-4 inches longer than the flat 56 style. I'm just hoping it won't look like a shelf there lol.

 

I have the AC brackets for a 401 Nailhead, but you lose the spark plug covers. You also need to swap to a 401/425 timing cover with the 401/425 fuel pump or the bracket will not fit. This is a mod I was going to do with the old engine, but I have no plans to disassemble the engine that is in the car currently. Therefor, I figured I could make brackets that are similar to the original 322 bracket, where the front is held on by the water log bolts and the rear is held on with a link from a stud at the intake manifold that goes around the spark plug covers and down to the lowest head bolt between the exhaust manifold. For sake of parts, I would just get one of those aluminum mini compressors, the condenser, dryer and all related parts from the same company and call it good. The local NAPA here has a hose fitting department, so making hoses would not be a problem.

 

I didn't think about a drain for the evaporator, but drilling a hole into the bellhousing bump could be made to work, and sealed, with a tap.

 

Willis, I like your idea of sealing the car. I was going to go to the army surplus store outside Joint Base Lewis-McChord and get some military air craft insulation for the floors. My headliner is still in really good condition, so no messing around there.

 

Edit: based on the information on the Vintage Air website, here's the size comparisons of the Heritage and Mark IV units available. The red line is to the knob of the heater controls.

 

Looks like the Heritage unit would be a better fit, but it's just black plastic with chrome louvers. The Mark IV I think looks better, but it has way too much shelf  hanging out.

Edited June 26, 2017 by Beemon (see edit history)

[buick5563]

Another consideration is which side do the hoses enter and exit the unit. That is why I used the Old Air Products. The hoses are on the passenger side which means they don't have to go an additional two feet and be messing with your foot on the accelerator pedal. I just drilled the drain into the bell housing bump and let it drain out there. No problem...just a hole. Like you mentioned above,  I had a compressor mount fabricated that just uses two mounting points at the generator stud and the top water pump stud. Hasn't moved and very solid.

[buick5563]

[old-tank]

All under dash units are 'knee knockers', but the currently available units are better than the ones when these cars were contemporary.  They do cool well, but the center passenger is singing "keep me cockatoo cool..." after awhile.

A 55-56 factory air compressor bracket can easily be adapted to the Sanden style compressor; or use an adapter for the old York/Tecumseh mounts.

[Bill Stoneberg]

Thats bad Willie...

 

[Beemon]

6 hours ago, buick5563 said:

Another consideration is which side do the hoses enter and exit the unit. That is why I used the Old Air Products. The hoses are on the passenger side which means they don't have to go an additional two feet and be messing with your foot on the accelerator pedal. I just drilled the drain into the bell housing bump and let it drain out there. No problem...just a hole. Like you mentioned above,  I had a compressor mount fabricated that just uses two mounting points at the generator stud and the top water pump stud. Hasn't moved and very solid.

Do you have any more pictures of this install? Both what it looks like under the dash and your custom bracket? 

[EmTee]

So...  I gather that the fact that you've created this thread means the ol' girl is runnin' strong -- strong enuf to spin an auxillary compressor anyway! 

[Beemon]

57 minutes ago, EmTee said:

So...  I gather that the fact that you've created this thread means the ol' girl is runnin' strong -- strong enuf to spin an auxillary compressor anyway! 

 

Despite the 4GC stumble, she pulls pretty hard. We have some steep hills where I live, where truck compression braking is banned. The NAPA store I go to is at the bottom and I'm at the top. Sometimes I forget the speed limit is 35 going up... 7*BTC, premium pump gas and full throttle... you can pull some carriages.

[NTX5467]

In the middle 1960s, when hang-down add-on a/c was popular, one of the premium brands was "Mark IV".  It looked the best and was supposed to perform the best.  Kind of looked like the Ford Select-Aire premium a/c unit.  Pretty upscale compared to some!

 

When Dad and I went shopping for an add-on a/c unit for our '61 BelAir, almost everybody had a unit they could take to the car and see how it would fit the dash panel.  Some units were longer than others.  Most had a larger body than the air distribution portion of the case.  In order to get a good fit on the one we ended up choosing, it was necessary to angle the rear downward to minimize intrusion on the center passenger's area.

 

The next year, we went to Houston in the summer (to attend baseball games in the then-new AstroDome.  In the humidity, it would freeze-up.  As it thawed out, we made sure the vents were aimed upward so that any droplets would land in the back seat, as we slunked-down in the front seat.  My aunt caught on to that little deal.  Such fun!

 

Those were the daaaayyyysssssss . . . .

 

NTX5467 

[oldstyle]

Not to hijack your thread but I was wondering if your concerned about the extra load causing the engine to overheat. I've always wanted to add AC to my 57 Buick but it runs warm in the summer as it is. 

[Beemon]

Nope, I have a 6 blade fan on an HD clutch. I have never seen the red of the gauge unless it's been turned off and let to sit for a minute on a hot day. 

[Beemon]

Some questions:

• What is the difference between an AC and non-AC generator, except the pulley? Are they internally the same, just with a smaller diameter 2 groove pulley? Does anyone have the actual diameter of the pulley?
• Will 401/425 3 groove pulleys fit okay on the crank? (water pump should be OK?)
• Mike, I couldn't find the thread, but I remember you modified a power steering pulley to work with AC. I have a spare one, can you share your wisdom once again? It seems the forum purge strikes again.

Thanks guys!

[Ben Bruce aka First Born]

6 hours ago, oldstyle said:

Not to hijack your thread but I was wondering if your concerned about the extra load causing the engine to overheat. I've always wanted to add AC to my 57 Buick but it runs warm in the summer as it is. 

Raul, what do you call warm? If over 200, The radiator IS partially plugged.

 

  Ben

[buick5563]

The 401 pulleys have different holes. I bought a few trying to modify and or sell to customers.

I will take some pics later today. 

[old-tank]

Don't worry about the generator.  Any that charges will work.  My original Special with under dash unit worked fine.  My low mileage original with factory air has the the standard generator (parts book references a different one for A/C cars).  

I have had generator issues with mine:  first was a shorted field, had another "rebuilt" locally with 'heavy duty components' and it failed over and over (4x).  Finally put the armature from the original shorted field one and only changed the brushes this year after 30k miles of running factory air.

[oldstyle]

3 hours ago, Ben Bruce aka First Born said:

Raul, what do you call warm? If over 200, The radiator IS partially plugged.

 

  Ben

 

Not sure but possible. The radiator has been recored and upgraded, 6 blade fan, and electric fan. Of course the summers here reach above 100 (last week had about 5 days in a row >100).  Only gets really hot when idling or stop and go traffic. I think every nailhead I've ever owned has ran on the warm side. 

Hopefully this is pertinent enough to the thread as to not derail it. 

[Beemon]

1 hour ago, oldstyle said:

 

Not sure but possible. The radiator has been recored and upgraded, 6 blade fan, and electric fan. Of course the summers here reach above 100 (last week had about 5 days in a row >100).  Only gets really hot when idling or stop and go traffic. I think every nailhead I've ever owned has ran on the warm side. 

Hopefully this is pertinent enough to the thread as to not derail it. 

 

I've heard you're only supposed to use one fan or the other, not both. This could cause air flow issues across the radiator. Also with electric fans, the CFM is important to know, as well as which direction it flows. The HD clutch in my car spins at about 50% water pump speed. Even on the hottest days I have never heard it kick in. I have a 3 core radiator, too. And we also deal with 75% or more humidity. What kind of pump fan are you using? 

[oldstyle]

No clutch, 6 blade and I cant remember the length of the blades but much longer then normal. Also running a shroud. Electric fan cfms were the largest I could find at the time. Long time ago so don't remember the exact number. Electric fan made the biggest difference. I'm sure it blocks some air at high speeds but so far that's not a issue.

[Beemon]

You should try for one day taking off the mechanical fan and see how it runs. You might be surprised how much of a difference it might make. Or it could go the other way, but you never really know. It's not a flex fan, is it? They say for optimal flow through a fan shroud, you need 1" spacing all around (18" fan in a 20" shroud - this is for engine flex), and the fan has to sit halfway in and halfway out. Also what kind of thermostat are you running? How many pump vanes? What type of coolant? Cap pressure?

[oldstyle]

Not a flex fan. Correct spacing and set up of fan/shroud. 160 deg thermostat, I think. Standard rebuilt waterpump-not ac. Cap pressure is 13lbs, maybe. Ha, I haven't had to think about all this in awhile, amazing what Im not sure of. I do remember that cap pressure was low because Im using the original tanks with a new core.

 

Thanks for the helpful input!

[Beemon]

I would probably flush your coolant, double check your t-stat with maybe replacing it with a new one. Double check your rad cap, too. Brass radiators don't like any more than 7lbs of pressure. Maybe even pop out some freeze plugs and see if the block needs some cleaning? Coolant does break down over time and just like brake fluid, should be replaced every couple years whether you drive it alot or not.

[oldstyle]

Good points, thanks.

[buick5563]

Here are the pics of my bracket based on a factory bracket. Much like the original, belt tension is achieved by adjusting the generator.

I don't have pics of my setup cuz my car is up in the air (on a lift), and I can't get to it with a ladder. I will try and get a pic soon. Honestly, I can't believe I don't have one pic in my phone of my setup....

[buick5563]

Found some of a customer's car

[buick5563]

More, including the condenser and side to side comparison of the bracket with factory bracket beside. If you have an original 401 bracket, you can use that by expanding the holes to fit a Sanden style compressor.

Apparently, this customer got even colder air than my previous pic of my IR gun.

[Beemon]

Mike, no rear bracket? How sturdy is it? Does it bounce? 

[buick5563]

 Nope. I initially wanted to make a rear bracket, but there is literally no shaking and once you bolt it, you can't move it with your hands. It's made out of 3/16" steel. My prototype was bent in my vice with a big ass hammer and a Bosch electric jigsaw. Nothing fancy.

[Beemon]

I guess if it is made from aluminum, it should be as light as the power steering pump, so makes sense! Thanks for the pictures, I have never seen the original bracket before. I'll most likely use the 401 bracket as a template, and then use the bolt spacing of the compressor to make the top, like you did. Looks like the driver side compressor bolt hole is in line with the water log bolts? What's the spacing from the top log bolt to the compressor bolt? If you have that on hand, that is...

[NTX5467]

Shaking and "movement" are important criteria, BUT operational harmonics can do far more damage than being able to shake with your hands.  With the shorter length, the frequency would probably be pretty high and out of the critical range for the material used AND its physical size.  The axial compressors are much smoother in operation than the other designs, by observation, though.

 

On many of the GM A-6 installations, there was the normal front mounting and a rear stabilizing bracket of some sort.  In doing many aftermarket intake manifold installations, that rear bracket must be either removed or modified if it attaches to an intake manifold bolt.  I ran into that issue on my Camaro and deleted the rear bracket.  The factory Chevrolet brackets are usually MORE complex and of thicker material than what other OEMs seem to use, so no issues of any kind (for very well past 100K, or 500K+ miles).  Material thickness and selection seem to be the reason, in this case.

 

When Chrysler went to the similar Denso compressor for the 1980 model year, on the LA motors, they used a boss on a modified intake manifold (rotating the thermostat housing in the process) and a simple bolt for the rear stability issue.  Their bracket system is generally simpler and less massive than Chevy uses.

 

NTX5467

 

[buick5563]

8 hours ago, Beemon said:

I guess if it is made from aluminum, it should be as light as the power steering pump, so makes sense! Thanks for the pictures, I have never seen the original bracket before. I'll most likely use the 401 bracket as a template, and then use the bolt spacing of the compressor to make the top, like you did. Looks like the driver side compressor bolt hole is in line with the water log bolts? What's the spacing from the top log bolt to the compressor bolt? If you have that on hand, that is...

I used a 401 bracket on my wagon before I made this one. I don't remember what I had to modify, but it was minimal. I think I actually made the bracket taller after the one pictured to provide better geometry for fan belt adjustment. I HATE the one that Centreville sells for 401 engines. It is giant and gaudy. I wanted to minimize the engine compartment intrusion. I also decided only to use one of the crossover studs as a mount in case I ever sold them to other peeps who would definitely at least have that one stud, so that it was a "one stop shop" kinda thing.

It is 4 1/2" from crossover to right bolt hole. I am attaching another pic of the last one I had made up with a slotted Hole on the left side for a little more tensioning options. 

PS, I have one of these left without the slotted adjuster, and that is my final "run" 

 

Edited June 29, 2017 by buick5563
Added pic (see edit history)

[old-tank]

2 hours ago, NTX5467 said:

The axial compressors are much smoother in operation than the other designs, by observation, though

The modern compressors are smoother and the Sanden style is lighter, smaller and more efficient, but are exactly the same design as the A-5 compressors on my 55's; and these were used until the A-6..

Any bracket you think might be needed is easy to fabricate...details if needed.

[Bill Stoneberg]

Quote

Any bracket you think might be needed is easy to fabricate...details if needed.

 

Like Mike said  a Big assed hammer, a vice, drill  and a saws all or grinder and you can do it.  Make the template out of cardboard (like a file folder, not a cardboard box) to get it to fit and then start cutting, drilling and beating till it fits.

[NTX5467]

12 hours ago, Bill Stoneberg said:

   drilling and beating till it fits.

 

(Kind of makes it sound like the square dowel into a round hole . . .)

[Beemon]

I found this on Ebay today. I saw it locally on Craigslist and thought it was the original setup, but turns out the same guy that is doing the brake pedal conversion has now also done a stock-like firewall AC system that is supposedly smaller profile than the factory. Looks pretty clean, just thought I would pass it on! A setup like this could look pretty good, would just then need to grab the dash pad and controls so you can really get that 56 AC flowing.

[NTX5467]

Brass radiators and 7psi caps?  What about the later OEM caps for 15-17psi?  Don't forget about the integrity of the heater core, either!

 

I don't know that a "pusher" electric fan would block that much air flow, other than the housing, as the air going through the fan will spin it faster than the electricity might run it.  Same as a clutch fan.

 

NTX5467

[dons56]

in the case of the original factory air, several upgrades were made to what was standard.  A 5 blade fan replaced the 4 blade fan.  A larger generator was also required.  The blower motor is also beefier.  I am not sure if a larger radiator was also in that package or not.  I have an original factory air system waiting to be installed in my Special Riviera but unfortunately the parts are at my sister's house 1,000 from me.  My son, SpecialEducation, has all the information on this conversion if we can get him involved...